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Consumers’ attitude formation toward an unknown product. How text and

pictures influence the process?

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Nevena I. Ivanova

Reg. No. 840528 383 110

MME- Marketing and consumer behaviour

Course: MCB 80433 MSc Thesis Marketing and Consumer Behaviour

University: Wageningen University and Research Centre, Wageningen, The Netherlands

Department: Marketing and Consumer behaviour

Supervisor: Arnout Fischer, Dr.ir.

Second supervisor: Gerben Bekker, Ph.D.

Date: 27/03/2013

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Contents Introduction ........................................................................................................................................................................ 4

Literature analysis ........................................................................................................................................................... 6

Attitude formation .................................................................................................................................................. 6

Cues............................................................................................................................................................................... 9

Hypothesis development .................................................................................................................................. 10

Method ............................................................................................................................................................................... 12

Results ................................................................................................................................................................................ 16

Discussion ......................................................................................................................................................................... 23

References ........................................................................................................................................................................ 26

Appendix A ....................................................................................................................................................................... 29

Appendix B ....................................................................................................................................................................... 33

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Introduction

"Fifty years hence we shall escape the absurdity of growing a whole chicken in order to eat the

breast or wing by growing these parts separately under a suitable medium."

Winston Churchill, 1932

According to the Population Reference Bureau (PRB) the world population is currently 7 billion

people, both the sixth and seventh billion were reached in only 12-year periods. It is expected

that the population will reach eight billion in the same period of 12 years which is in 2023 (PRB,

2011). This rapid growth raises serious doubts about the possibility to provide enough food.

The livestock sector is socially and politically important, providing 40 % of the agricultural

gross domestic product (GDP) and employing 1.3 billion people (Steinfeld, 2006). Livestock

products are providing the protein intake that is required for a human being and are

responsible for overcoming undernourishment. Besides the aforementioned advantages, the

livestock sector is a cause for a number of problems. Growing population and income, as well as

the changing food preferences of consumers, are a reason for the accelerated demand for

livestock products which contribute to the technical and geographical changes in the sector

(Steinfeld, 2006). These changes have a direct or indirect impact on the environment like air

and soil pollution; overexploitation of land and water resources, climate change. The area

engaged in grazing is 26% of the land surface, 33 % of arable area is used for growing livestock

feed crop production and the land surface of the planet is 30% occupied by livestock production

(Steinfeld, 2006). The livestock sector is responsible for climate changes contributing 18% of

the anthropogenic greenhouse gas emissions, which is more than the pollution caused by

transport; 64% of anthropogenic ammonia emissions (Steinfeld, 2006). The livestock sector

usage of water is mainly for crop irrigation which counts for 8 % of global freshwater use

(Steinfeld, 2006). Moreover, the use of antimicrobial agents in food animals causes

antimicrobial-drug resistance in humans consuming livestock products (Glynn et al., 1998).

Food-borne diseases represent a growing part of the public health problems worldwide. The

most common problems are gastrointestinal symptoms which can lead to chronic, life

threatening symptoms (WHO, 2012). The mentioned disadvantages create the need for

alternative sources of meat products that can reduce the environmental and public health

problems. Scientists introduced and have already successfully created in vitro meat also called

cultured meat (CM) using tissue-engineering techniques. There are different approaches to this

so called in vitro meat production system (IMPS) like scaffold/cell culture based and self-

organising/tissue culture techniques, organ printing etc., which we are not going to discuss in

this report. (Bhat & Bhat, 2011)

It can be assumed that consumer’s preferences are in favour of in vitro meat because it is a kind

of meat that reduces all the disadvantages created by livestock products. On the contrary,

consumers see in vitro meat as physically and/or morally not acceptable due to its perceived

‘unnaturalness’ (Edelman, 2003; European commission, 2005). A similar case can be seen in the

face of consumers’ attitudes toward genetically modified products (GMO’s). Consumers were

not supposed to have any obvious objections to the specific food and yet according to the

European commission (2010), Europeans are not in favour of the development of genetically

modified food. Consumers do not see the benefits and consider the GMO’s unsafe and harmful.

Consumer’ evaluations of GMO’s were enormously influenced by pictures and messages, where

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these products were presented as something bad, as ‘Franken food’. It will be interesting and

useful to investigate how consumers will approach such an innovative product as in vitro meat

on the market.

Attitudes are learned, global evaluations of an object (i.e. cultured meat) and it is well-known

that they influence our behaviour (Fazio, 1995). Attitudes are described as state of readiness

that guides consumer’s behaviour and are based on both affect and cognition (Gawronski &

Bodenhausen, 2006). Thus, people’s feelings, thoughts and behaviour towards in vitro meat

could be favourable or unfavourable.

There are many theories that explain how attitudes are formed and could be changed, that are

used by researchers. These theories give explanation of reasons why consumers favour one food

rather than another. Especially in the cases where one of the choices, that could be considered

as better because of certain advantages, is being disregarded without any obvious reason. Social

psychologists have focused their attention on the dual attitudes models, called like this because

they argue that people hold separate unconscious, automatic, implicit and conscious,

deliberative, explicit attitudes. (Wilson et al., 2000; Greenwald & Banaji, 1995) While the

Elaboration likelihood model (ELM) explaines the two systems of information processing and

the factors influencing the information processing (Petty & Cacioppo, 1986). The first type of

processing is heuristics based while the second is more elaborate. The heuristic process uses

simple, efficient rules that can guide decisions without effort, while the elaborate process

requires deeper processing and some effort. Which process will be triggered depends on the

situational context and the cues present in the environment.

The aim of this study is to analyse how attitudes towards unknown product such as in vitro

meat, are formed and how cues, present in the environment, will affect this formation process.

Furthermore, the importance of how the product is communicated to the consumers, in terms of

pictorial or textual representation, will be investigated in order to show which attitude

formation process will be triggered.

Extensive prior research has focused mostly on explicit attitudes (Greenwald, 1990) and some

on implicit attitudes towards known attitude object. However, little attention has been paid to

the formation of implicit attitudes toward unknown objects. Because both processes differ

fundamentally from each other they require different measurement instruments. This report

will use the Implicit Association Test (IAT) to measure the implicit attitudes and semantic

differential scale questionnaire to measure the explicit attitudes. The Implicit Association Test

(IAT; Greenwald at al., 1998) is a reaction time method that measures the individual differences

in the strength of associations among concepts. This report focuses on measuring the implicit

attitude toward an unknown attitude object (i.e., in vitro meat) that does not have an opposing

relevant category which makes the traditional IAT not suitable for the purpose of the

experiment. Two variations of the IAT exist- Single Category IAT (SC-IAT; Karpinski et al., 2006)

and Single Target IAT (ST-IAT; Wigboldus et al., 2006). Both measure a single attitude object

and two categories with polarized valence (i.e., positive vs. negative). The only difference is that

SC-IAT has response time window which makes it not suitable for measuring implicit attitudes

toward unknown object because creates time pressure that could limit the participants’

answers (Bekker et al., 2012) . Therefore, the single target IAT (ST-IAT) was used to measure

the mental associations individuals hold about in vitro meat because this kind of test is similar

to IAT and measures the associations with a single target without the need of an opposite

category (Wigboldus et al., 2006).

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Literature analysis

The purpose of this report is to investigate how consumers form attitudes towards such

innovative product as in vitro meat. It is specifically focused on exploring how cues like pictures

and text influence this attitude formation process. Several theories, which will be discussed in

this part, could help us follow the process and understand it. The dual attitudes model

(Greenwald & Banaji, 1995; Wilson et al., 2000) argues that people can hold two different

evaluations towards the same attitude object, while the Elaboration likelihood model (ELM)

(Petty & Cacioppo, 1986) explains the two systems of information processing and the factors

influencing the way consumers process the cues in the environment in order to form their

attitudes. Furthermore, literature on categorization and inference making will be reviewed in

order to help us understand how a new product as in vitro meat will be classified by consumers.

Two representations, pictures and text, and their influence, are described in separate section.

Finally, the integration of these theories in a conceptual model could help us examine how

consumers will form their attitude toward in vitro meat and what factors underlie this process.

Attitude formation

Attitudes are evaluations of certain attitude object that guide our behaviour and more

specifically, they represent the associations between the object and the summary evaluation of

that object (Fazio, 1995). Several sources of information could lead to an evaluation which does

not mean that attitudes should be seen only as assessments of the object’s attributes or as

judgements based on certain beliefs towards the object (Zanna & Rempel, 1988).They could also

be coming from some kind of emotional response that this object evokes or could be based on

all of these processes. (Fazio, 2007)

Attitudes commence from different mental processes, they can be divided according to the level

of consciousness they operate in (Wilson et al., 2000). Implicit attitudes are automatic,

unconscious evaluations. People cannot escape the activation of associated evaluations when

they encounter the attitude object; hence, it is uncontrolled, automatic (Shiffrin & Dumais,

1981). Implicit attitudes, which people are unaware of, predict uncontrolled and impulsive

behaviour. People’s conscious behaviour is guided by explicit attitudes, which are deliberative,

conscious evaluations of an attitude object (dual attitude model). This attitude could be the

result of more careful scrutiny of information regarding the attitude object (Ajzen & Fishbein,

2000). Which attitude will be favoured depends on whether people have the cognitive capacity

to regain the explicit attitude or whether the explicit attitude can prevail over the implicit

attitude. (Wilson et al., 2000) People tend to rely on automatic processing unless they have the

motivation and the cognitive capacity to process consciously (Smith & DeCoster, 2000)

The most important assumption of the dual attitude model is that implicit and explicit attitudes

have different mental representations. Implicit and explicit attitudes are stored in different

areas of the brain (DeCoster et al., 2006) thus people could hold both deliberative (explicit) and

automatic (implicit) attitude of different valence towards the same attitude object. Attitudes

can operate in different situations which lead to the construction of these attitudes in specific

contexts different for each of them. Implicit attitudes guide behaviour in spontaneous situations

when people are not thinking actively, while the explicit attitudes guide behaviour when people

are actively engaged (Dovidio et al., 1997).

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The implicit and explicit attitudes are the result of separate mental processes. Implicit attitudes

follow from associative processes; while explicit attitudes are the result of propositional

processes such as deliberating on the message argument (Rydell & McConnell, 2006). These

mental processes are governed by separate mental systems (DeCoster et al., 2006; Rydell &

McConnell, 2006).

Some theories effectively explain the differential impact of implicit and explicit attitudes on

consumers’ behaviour (Wilson et al., 2000; Fazio & Olson, 2003). Most of these studies are

focused on explaining consumers’ attitudes toward well-known objects but in daily life people

encounter new objects all the time. They have no previous experience with these objects thus

they have not constructed an attitude yet. Only a few studies focus on the automatic evaluation

of novel stimuli suggesting that it is an on-going process (Duckworth et al., 2002; Ranganath &

Nosek, 2008) However, formation and changes in implicit attitudes toward an unknown attitude

object still lack explanation.

As mentioned earlier attitudes can operate in different situations which lead to the construction

of these attitudes in specific contexts different for each of them. The factor that will have

influence on which attitude will be triggered is the extent to which an attitude object is

perceived as relevant or not for the consumers. People will process information about an

attitude object according to the relevance they assign to this object. The Elaboration likelihood

model by Petty and Cacioppo (1986), which will be addressed in the next paragraph, gives

thorough explanation of the information processing. There are a lot of factors that influence the

context in which attitudes are constructed, and how people process information about a

product is one of them.

People process information in a quick, effortless manner unless they have the ability and

motivation to perform more extensive, effortful thinking. The first type of processing is called

the peripheral route and uses simple decision rules to assess information (Petty & Cacioppo,

1986; Chaiken, 1987). Previously encountered stimuli are being encoded in memory and later

associated with salient features of the current stimulus. Past experience influences the

processing of current information. This type of processing occurs on an unconscious level so

people are aware only of the output, not the information used for the output (Smith & DeCoster,

2000). The cues present in the environment are used to guide consumers’ decision.

The other type of processing operates on more conscious level and requires more intention and

awareness. This processing is called the central route and is more effortful and time-consuming

(Petty & Cacioppo, 1986; Chaiken, 1987). People elaborate on the information and carefully

scrutinize the arguments. They are aware of the information used for the output and the steps

they undertake to arrive at a conclusion. This processing mode occurs if the person has ample

cognitive resource to engage in it and is motivated to do so.

There are certain conditions that underlie the use of both processes and the most important of

them are- motivation and ability. The motivation depends on the relevance of the issue for

people’s life. If something is perceived as highly relevant for people’s lives, they tend to process

certain related information through the central processing route (Petty & Cacioppo, 1986).

People will actively think about the attitude object and consider the information carefully which

will lead to the formation of explicit attitude toward an attitude object. On the other hand, in

case something is not of personal consequence, people will process the information

peripherally. They will use cues present in the environment or simple heuristics that will lead to

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automatic, unconscious evaluation which will be the reason to form implicit attitude towards

the attitude object. There are certain situations in which the ability to scrutinize information is

undermined- the presence of distraction, lack of sufficient knowledge about the topic, the

information about the topic is not easily available (Petty & Cacioppo, 1986). If people are

distracted and their motivation to elaborate is low, they will use heuristics. As was mentioned

earlier, in vitro meat is a product that is not yet released on the market thus consumers have

low knowledge or no knowledge about it. In this situation people tend to use heuristic

processing. Certain cues present in the environment and the situational context will influence

the way they form attitude toward this unknown object.

The ELM model can help us understand how individuals will approach a certain attitude object

and how we can use this knowledge to construct messages that will be processed in certain way

(Perloff, 2010). If we understand the factors that affect people and how they think about an

object, we have better chance to target individual’s attitudes.

People use cues to help them simplify their decisions about an issue. Some cues are more

salient in affecting the heuristic processing of information, while others evoking more elaborate

thinking. The cues that will be present in the environment in that particular moment will be

important for the way people will process the information about a product. In vitro meat is an

innovative product that is unfamiliar to the consumers; therefore, the cues will influence how it

will be perceived.

Consumers make sense of the world around them by organising the knowledge about it in sets

of consumer expectations. This knowledge of objects, situations, and events is represented by

schema or knowledge structures. If the knowledge about an object they encounter overlaps with

their existing knowledge, categorization will occur- the object is put in one category with others

that have similar characteristics. Once categorized, consumers make inferences of the object’s

features. (Miller et al., 2005)

People do not possess knowledge about in vitro meat therefore they do not have knowledge

structures about it. When confronted with a new product, consumers make sense of it by

placing it in an existing category, where products that appear similar to each other are stored

(Loken et al., 2008). They use the information, which is constructed about the category, in order

to assign the product to certain category. Based on this knowledge, consumers make inferences

about unknown attributes or features of the new product or simply form evaluations (Miller et

al., 2005). In vitro meat is a new product and its appearance does not resemble any other kind

of meat. People not only do not have information about this product but they also lack any prior

judgement of it. Therefore, they will have to rely on the product features in order to establish

correlation and place it in certain category (Loken et al., 2008; McClelland & Rumelhart, 1985).

The features of the product are depicted from the way it is represented using pictures or words.

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Cues

Cues, such as the representation of a new product, will guide people to use either heuristics or

more elaborate thinking to process the relevant information. Text, about the new product, and

pictures of it, are considered external representations, which lead to the construction of internal

mental representations of the content described in the text or shown in the picture (Schnotz,

2002).

Both text and picture are assigned to different classes of representations- descriptive and

depictive accordingly. Both of them are associated with the content they represent but while

text is constructed of symbols with arbitrary structure, pictures are iconic signs on either

concrete or more abstract level. Consumers extract information from the representation with

the help of available procedures which depend on its structure and the procedures that operate

on the structure (Palmer, 1978). Text and picture’s information is processed in different

cognitive subsystems: verbal and imagery systems with the only difference that pictures

operate in both systems while text only in the verbal one (Clark & Paivio, 1991; Mayer, 1997).

People select relevant words from descriptive representation and construct text base which is

then organised into verbal mental model of the described situation. In the case of depictive

representation, people select relevant images and create an image base which is then organised

into a visual mental model of the situation shown in the picture (Mayer, 1997). When

encountering a new product (i.e., in vitro meat), information from multiple categories might be

relevant, and therefore, changing the salience of a certain category through the representation

of the product, will influence the extent in which this category will be used in making inference

about the product. The information, derived from depictive or descriptive representations,

which is first encountered or cued by an advertisement, influences consumer’s categorizations,

expectations, and preference (Loken et al., 2008). This information, derived from depictions and

descriptions, serves as a cue for processing the innovative product using either heuristic or

more elaborate thinking.

Research on the use of depictions and descriptions has shown that depictions are processed

more superficially and faster in comparison to descriptions (Weidenmann, 1989). Pictures

allow for easier access to information about meaning (Nelson et al., 1977; Pellegrino et al.,

1977); they require more time to name and less time to categorize than words (Potter &

Faulconer, 1975). The information from depictions takes less mental effort to be processed than

the information derived from descriptions (Salomon, 1984). Therefore, we can assume that

pictures will provoke heuristic processing in consumers. This could lead to forming an

automatic, implicit attitude toward the attitude object (i.e., in vitro meat).

Words, on the other hand, allow for easier access to phonemic information required in naming

compared to pictures (Nelson et al., 1977; Pellegrino et al., 1977). Descriptions requires more

mental effort to be processed (Salomon, 1984) therefore they will be more elaborately

processed by consumers. This could lead to the formation of deliberative, explicit attitudes.

However, the influence of depictive and descriptive representations on attitude formation

towards unfamiliar attitude object is still unknown.

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Fig. 1 Conceptual model

Hypothesis development

In vitro meat is a type of meat grown from animal muscle tissue. It is an innovative product not

yet introduced on the market thus the representation of such product- textual or pictorial- will

have influence on the way consumers will form their attitudes towards cultured meat.

The information that is first encountered or cued by an ad will have stronger influence on

consumers’ categorization, expectation, and preference (Loken at al., 2008). For consumers the

environment in which they will encounter information about that product is important for the

way they will process this information. Certain situations, like the presence or lack of cognitive

ability to scrutinize the information, will have impact on the way consumers will process this

information.

Every day, consumers are overwhelmed by all kind of information on their work place or during

their daily activities which leads to undermined cognitive resources. Encountering information

about unfamiliar product under conditions of cognitive depletion will lead to the use of simple

strategies to scrutinize the information (Petty & Cacioppo, 1986) and thus more extreme

automatic implicit attitude.

H1: Low cognitive resource compared to high cognitive resource will lead to more extreme

implicit attitudes towards in vitro meat.

The use of cues simplifies the decision that consumers have to make every day on the highly

competitive market. Pictures are depictive representations that have iconic meaning on either

concrete or more abstract level and are used as cue. Pictures of unfamiliar product such as in

vitro meat or a by-product will lead to the use of heuristics and thus forming more extreme

implicit attitude.

H2: Pictorial information about in vitro meat compared to textual information will lead to

more extreme implicit attitudes.

H3: Pictorial information about in vitro meat under condition of low cognitive recourse will

lead to more extreme implicit attitude than the implicit attitude that textual information

will create.

Representations Processing Attitudes

Pictures

Text

Heuristics

Elaborate

Implicit

Explicit

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On the other hand, when confronted with information under conditions of high cognitive

resource, consumers will use more elaborate processing which will evoke the formation of

explicit attitudes. Text is descriptive representation, constructed of symbols with arbitrary

structure which requires more mental effort to be processed (Salomon, 1984). Therefore, under

conditions of high cognitive resource, text will cause the formation of explicit attitudes.

H4: High cognitive resource compared to low cognitive resource will lead to more extreme

explicit attitudes towards in vitro meat.

H5: Textual information about in vitro meat compared to pictorial information will lead to

more extreme explicit attitudes.

H6: Textual information about in vitro meat under conditions of high cognitive recourse will

lead to more extreme explicit attitude than the explicit attitude created by pictorial

information.

Fig. 2 Hypothesis model

H3 H2 H1

H4

H6 H5

Heuristics / Elaborate

Elaborate /Heuristics

Pictures / Text

Text / Picture

Implicit attitudes

Explicit attitudes

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Method

The current report examines how consumers form their attitude toward an unknown object

(i.e., in vitro meat) and what the effect of pictures and text is on this process. Implicit and

explicit attitudes and the processes that characterize them are very different in their nature.

Therefore, two different kinds of measures were used. The ST-IAT (Wigboldus et al., 2006) was

used to measure the positive and negative associations that consumers have with two different

stimuli sets (pictorial and textual representation) of in vitro meat. In order to measure the

implicit attitudes under conditions of low cognitive resources half of the participants were

cognitively depleted using a demanding writing task, while the other half had easier writing

task. The explicit attitude of participants was measured using semantic differential scale,

followed by manipulation check questions and socio-demographic questions.

Participants

Students from Wageningen University participated in the computer-based experiment in the

autumn of 2012. The experiment was conducted in individual cubicles on laptops that run on

Windows 7 and have 17.3 inch display with 1600x900 resolution. External mice and keyboards

on which the response keys were marked for convenience in yellow and blue colours were

provided. Inquisit 3 software was used to measure the response time of participants (Inquisit,

2011). The sample consisted of 181 participants that were native Dutch speakers. The

respondents received 2 Euro for their participation in the experiment.

Design

The study had an experimental 2 (pictures vs. words ST-IAT) x 2 (depleted vs. non-depleted)

between group design. Several block randomizations were applied in order to avoid order

effects and response key preference: (a) random allocation of participants to the conditions; (b)

response key assignment for positive and negative words and pictures (left or right); (c) and the

order in which in vitro meat words was paired with the positive and negative dimensions.

Because pictures and text are processed in different cognitive systems- verbal and imagery

(Clark &Paivio, 1991; Mayer, 1997) mixed (pictures and text) evaluative dimensions were used

in ST-IAT. After completing the ST-IAT task participants were asked to answer a questionnaire

in order to examine their explicit attitude.

Stimulus material

For both the textual and pictorial ST-IAT the stimulus material consisted of 5 positive (e.g.,

freedom) and 5 negative words (e.g., tragedy), 5 positive and 5 negative pictures (provided in

Appendix A). The only difference was that for the textual ST-IAT 4 words representing in vitro

meat were used (e.g., muscle stem cell, see Appendix A), while for the pictorial ST-IAT- 4

pictures representing in vitro meat. The words for the evaluative dimension were taken from

previously published IAT research (Greenwald et al., 1998). Both the words and the pictures for

the evaluative dimensions and for the cultured meat were selected on the basis of a pre-test.

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The pre-test was conducted with students from Wageningen University. They were asked to fill

in a questionnaire where the words and pictures were evaluated on the basis of 7-point Likert

scale. The words and pictures were pretested on association with in vitro meat and association

of the words and pictures with each other. The positive evaluative words and pictures were

selected on the basis of highest mean score while the negative on lowest mean score. The in

vitro meat words and pictures were also chosen based on highest mean score (results provided

in Appendix A).

Cognitive resource depletion manipulation

The cognitive resources of participants were depleted using Schmeichel’s (2007) procedure.

Varying the degree to which participants’ have to inhibit their dominant writing tendencies in

order to complete an essay correctly. This task requires participants to write a short essay

without using words that contained either the letters A and N (depletion condition) or the

letters X and Z (no-depletion condition). Participants engaged in this task, which we refer to as

the ‘‘writing task,’’ for 6 minutes.

Measures

Implicit attitude measures The implicit attitudes were measured using the D score that divides the difference between test

block means by the standard deviation of all the latencies in the two test blocks (Greenwald,

Nosek & Banaji, 2003). The response latency is computed from the response speed which

respondents used to classify objects from the moment they appear on the screen. The criteria

used for the latency was taken from Greenwald et al. (2003): participants with more than 10%

of latencies smaller than 300ms and larger than 10 000ms were removed from the sample.

Explicit attitude measures The explicit attitudes toward in vitro meat were derived from Crites and colleagues (1994).

Semantic differential scale was used for the question which was the same: Geef op de

onderstaande schaal uw reactie ten opzichte van kweekvlees (...); the scales were divided into

affective (e.g., 1=hatelijk(hateful); 7=hartelijk(love)), cognitive (e.g., 1=nutteloos(useless);

7=nuttig(useful)) and general (e.g., 1=negatief(negative); 7=positief(positive)) (full list provided

in Appendix B).

Manipulation check measures The explicit attitude measure was followed by several questions. The cognitive resource

depletion was checked by asking participants the question ‘how tired were you after the writing

task?’ on a 7-point scale (1= not at all tired and 7= extremely tired); ‘how tired do you feel at this

moment?’ (1=not at all tired and 7= extremely tired). The association of pictures and text was

measured with questions that individually targeted the words and pictures (provided in

Appendix B). The level of knowledge on in vitro meat was measured with the question ‘to what

extent were you familiar with in vitro meat prior to your participation in the experiment?’

(1=unfamiliar, 2=a little bit familiar, 3=familiar).

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Socio-demographic measures The respondents were asked about any diet restrictions which could influence their responses.

They were also asked which hand is their dominant - left or right. Finally, participants were

asked to indicate their age, gender and initials of the programme they are enrolled in.

Extremity

The developed hypotheses in this report are measuring the extremity of the explicit and implicit

attitudes and how pictures and text influence it. Therefore, the data collected from the Likert

scales and ST-IAT test had to be transformed. They were first centred around zero and then the

Absolute value (ABS) of the zero centred data was used to produce a variable that contains only

the absolute values in the data. This means that all the signs are ignored: so -2 becomes +2 and

+2 stays +2.

Procedure

Participants were welcomed and instructed that the study measured the speed and accuracy of

categorizing words and pictures. No information about in vitro meat was provided beforehand

in order to avoid any biased response. Each participant received a number that was later used

to assign the groups. They were then asked to sign an informed consent followed by the

cognitive depletion task which differed in the degree of difficulty. Half of the participants

received the more difficult task which depleted their cognitive resources, the other half of the

respondents received less difficult task.

Before the actual test began a welcoming screen containing information on the task appeared.

Participants were then presented with an explanation of the response key mapping which

stayed during the task on the computer screen. They were asked to categorize words and

pictures by pressing one of two labelled keys (the A-key on the keyboard and the 5-key on the

numeric pad).

The participants worked through either pictorial ST-IAT or textual ST-IAT and were asked to

categorize words or pictures of in vitro meat.

The respondents reacted to four blocks of items- two practice blocks and two test blocks. For

the textual ST-IAT, respondents were presented with practice block consisting of 4 positive

words, 3 positive pictures, 5 negative words, 5 negative pictures and 7 in vitro meat words (24

trials). The participants were asked to react to the positive and negative words with one of the

response keys and to the in vitro meat words with one of these keys. The practice block was

then followed by test block. The respondents reacted to 7 positive words, 7 positive pictures, 10

negative words, 10 negative pictures and 14 in vitro meat words (48 trials). After this first pair

of practice and test block the participants had 15 seconds break followed by another pair of

practice and test blocks with the same number of trials. The only difference was in the

assignment of the target category (in vitro meat) to a response key. In the first part of the ST-

IAT, the target category was coupled with the right response key, while in the second part the

target category was coupled with the left response key. Thus, the participants started the ST-IAT

with the in vitro meat words coupled to the negative response key and after the break the in

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vitro meat words were coupled with the positive response key. Participants were asked to react

to the evaluative dimensions with the two response keys and to the in vitro meat words or

pictures with one of these response keys. The procedure for the pictorial ST-IAT was conducted

in the same manner only differing in the stimulus representation. After completing the tasks,

participants were given the 2 Euro reward.

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Results

Sample description

The sample consisted of 181 students from Wageningen University. Five respondents were

excluded in total: two of them responded in less than 300 ms in more than 10% of all responses;

the results from two other respondents were missing; the fifth respondent was excluded

because due to a technical error the writing task was interrupted. Thus, the aftermath was that

the valid responses of 176 students in total were used to analyze the data. The sample consisted

of 58 male and 118 female respondents, average age was 20.93 years (SD= 2.72). Detailed

presentation of the participants is provided in Table 1. The majority of respondents were

Bachelor students. The ANOVA test showed that educational level had no significant effect on

implicit and explicit attitude measures.

Table 1. Sample

Participants № 176

Gender

Female 118

Male 58

Age

17- 20 55

20- 25 106

25-30 13

30- 34 2

Education

Bachelor 123

Master 44

Other 9

ST-IAT

Pictorial ST-IAT Total 86

No cognitive depletion 44

Cognitive depletion 42

Textual ST-IAT Total 90

No cognitive depletion 44

Cognitive depletion 46

Cognitive Depletion condition

Cognitive depletion 88

No cognitive depletion 88

Right or left handed

Right handed 23

Left handed 153

Diet constraints

No diet constraints 158

Vegetarians 18

17

Data analysis

The results were analysed using SPSS program. An ɑ of .05 was used for all statistical tests.

Implicit measures Split-half correlation reliability was used to measure the reliability of the implicit attitude

measures. The procedure by Bekker et al. (2012, in prep.) was used to make sure that split-half

reliability was not dependent on randomness in the split. The sample was divided into 6 parallel

forms- odd and even, first 2 out of 4 trials etc. The Pearson correlation coefficient was calculated

for each of the parallel forms as an estimate of reliability. The results from the correlation test

could be seen in Table 2 below. The Pearson correlation for all parallel forms was between .32

and .56, which although low, is comparable to other IAT research (LeBel & Paunonen, 2011) and

therefore adequate. The effect sizes for Pearson correlation were interpreted based on Cohen

(1992): small (r>.10), medium (r>.30) and large effects(r>.50).

Table 2. Implicit attitudes reliability

Split-Half Pearson correlation coefficient

Odd trials Even trials

.556

First 2 out of 4 trials- Second 2 of 4 trials

.500

First 50% of trials (all positive and half of all target object trials) Second 50% of trials (all negative and half of all target object trials)

.484

Randomly 1: 50% of randomly drawn trials Randomly 1: 50% of randomly drawn trials

.471

Randomly 2: 50% of randomly drawn trials Randomly 2: 50% of randomly drawn trials

.560

First 50% of presented trials in experiment Second 50% of presented trials in experiment

.324

Explicit measures To assess the reliability of the variables that were measured by more than one item, Cronbach’s

alpha was calculated. The reliability coefficients of all constructs exceeded the .70 cut-off value

for reliability consistency.

Construct Cronbach’s Alpha Affective subscale explicit attitude .896

Cognitive subscale explicit attitude .892

General subscale explicit attitude .917

The data were checked for normality using the Kolmogorov-Smirnov test for normality. Most of

the variables were not significant (p>.05) which means that the data of these variables are

distributed normally; explicit attitudes D (176) = .044 p= .200; cognitive explicit attitudes D

(177) = .061, p= .200; general explicit attitudes D (176) = .067, p= .053. One of the variables

showed non-normal distribution, affective explicit attitude D (176) = .070, p= .034. The implicit

attitudes were also tested for normality and the results, D (176) = .066, p= .056, showed that the

scores are approximately normally distributed.

18

The variance inflation factor (VIF) and tolerance values were calculated in order to examine the

possibility for multicollinearity in the data. For the current model between cognitive and

affective subscale of explicit attitudes, the VIF value was well below 10 (VIF= 3.36) and the

tolerance statistics all well above 0.2 (tolerance= .298); therefore, we can safely conclude that

there is no collinearity between cognitive subscale and affective subscale of explicit attitudes

within the data.

Manipulation check The cognitive resource depletion was checked by asking participants the question ‘how tired

were you after the writing task?’ on a 7-point scale (1= not at all tired and 7= extremely tired).

After analyzing the results the Univariate factorial ANOVA test showed there was a significant

effect of tiredness after the writing task on the cognitive resource depletion F (1, 176) = 24.16,

p= .000. This was not due to the picture or text conditions F (1, 176) = .007, p= .931, or the

interaction between depletion task and picture/text F (1, 176) = .127, p= .722. The average

tiredness after the writing task was 2.99 (SD= .178) in the no cognitive depletion condition and

4.23 (SD= .179) in cognitive depletion condition.

The results from the question ‘how tired do you feel at this moment?’ (1=not at all tired and 7=

extremely tired) showed no significant differences of tiredness between the cognitive depletion

conditions F (1, 176) = 1.686, p= .196. This was not influenced by the picture and text conditions

F (1, 176) = 1. 975, p= .162, or the interaction between tiredness in the moment and cognitive

depletion conditions F (1, 176) = 1.046, p= .308. The average tiredness at the moment was 3.66

(SD= .172) in the no cognitive depletion condition and 3.97 (SD= .172) in the cognitive depletion

condition.

Association check The participants in the research were asked to indicate the level of association between the

pictures and words used in the ST-IAT test. After analyzing the data, the results showed that the

association between picture and word was highest for ‘laboratory’ and ‘tissue culture’ (see

Table 3).

Table 3. Association check

Word Mean St. deviation

Laboratory 6.10 1.317

Tissue culture 5.76 1.293

Stem cell 4.67 1.667

Cultured burger 4.42 1.897

Cultured steak 4.31 2.039

The associations between the pictures and the words used in the ST-IAT test were analyzed

using Univariate factorial ANOVA. The results showed that the word ‘laboratory’ had significant

effect on the picture/text condition F (1, 176) = 5.37, p= .022. The word ‘stem cell’ also has

significant effect on the picture/text condition F (1, 176) = 5.728, p= .018. The interaction

between picture/text condition, cognitive depletion condition and the word ‘cultured steak’ was

significant at F (1, 176) = 5.162, p= .024.

19

Socio-demographics At the end of the experiment participants were asked questions about their age, gender, prior

knowledge of in vitro meat, diet constraints, and which hand they used during the test (see

Table 1).

Implicit attitudes. The results showed that age had no significant effect on the implicit attitude

measures. Gender on the other hand showed a significant effect at F (1, 176) = 4.91, p= .028,

with male participants being more positive than female participants. Prior knowledge of in vitro

meat was not influential on the implicit attitude measures.

Explicit attitudes. When the same were tested for explicit attitudes, the results revealed that

there was significant interaction effect between the picture/text condition and the age of the

participants at F (1, 176) = 2.311, p= .019. Gender had no significant effect on the explicit

attitude measures, while prior knowledge proved to be significant at F (1, 176) = 7.192, p= .001.

Affective subscale. After analyzing the results for the affective subscale of the explicit attitude,

the results showed significant interaction effect between picture/text condition and age at F (1,

176) = 2.244, p= .023. Gender had no significant effect and prior knowledge was highly

significant at F (1, 176) = 7.248, p= .001.

Cognitive subscale. There was a significant interaction effect between picture/text condition

and age on the cognitive subscale of the explicit attitude at F (1, 176) = 2.196, p= .026. Gender

was not influential on the cognitive subscale, while prior knowledge had significant effect at F

(1,176) = 4.858, p= .009.

General subscale. Significant interaction effect was found between the cognitive depletion

condition, picture/text condition and age on the general subscale of the explicit attitude F (1,

176) = 2.230, p= .044. Gender had no significant effect and prior knowledge had a significant

effect on general subscale of the explicit attitude at F (1, 176) = 8.010, p= .000. Significant

interaction effect was also found between picture/text condition and prior knowledge on

general subscale F (1, 176) = 3.175, p= .044.

Being vegetarian showed no significant effect on both implicit and explicit attitude measures,

and any of the explicit subscales.

20

Hypothesis

In order to test all hypothesis univariate factorial ANOVA were carried out. After running the

test for extremity of the implicit and explicit attitudes, the same test was performed for both

attitudes without the extremity assumption. Furthermore, each of the subscale of explicit

attitudes – affective, cognitive, and general- were also explored for significant effects using the

same ANOVA test.

H1: Low cognitive resource compared to high cognitive resource will lead to more extreme

implicit attitudes towards in vitro meat.

The univariate factorial ANOVA test showed that the cognitive resource depletion had no

significant effect on implicit attitudes, F (1, 176) =.024, p=.877. The same no significant effect of

cognitive resource depletion were found on the extremity of implicit attitudes F (1, 176) = .297,

p= .587.

H2: Pictorial information about in vitro meat compared to textual information will lead to

more extreme implicit attitudes.

Picture/text condition had no significant effect on implicit attitudes F (1, 176) = .004, p= .950.

The same no significant effect was found on extremity of implicit attitudes F (1, 176) = 2.308, p=

.131.

H3: Pictorial information about in vitro meat under condition of low cognitive recourse will

lead to more extreme implicit attitude than the implicit attitude that textual information

will create.

No significant interaction effect was found between picture/text condition and cognitive

resource depletion condition on implicit attitudes F (1, 176) = .122, p= .728. There was no

significant interaction effect between the picture/text condition and cognitive resource

depletion condition on the extremity of implicit attitudes F (1, 176) = .003, p= .956.

H4: High cognitive resource compared to low cognitive resource will lead to more extreme

explicit attitudes towards in vitro meat.

The results from univariate factorial ANOVA test showed no significant effect of cognitive

resource depletion condition on explicit attitudes F (1, 176) = .616, p= .434. No significant effect

was observed of cognitive resource depletion condition on extremity of explicit attitudes F (1,

176) = .048, p= .827.

Univariate factorial ANOVA was conducted for each of the affective, cognitive, and general

subscales of explicit attitudes. The results showed no significant effects of cognitive resource

depletion on affective subscale of explicit attitude F (1, 176) = .239, p= .626; cognitive subscale

of explicit attitude F (1,176) = .703, p= .403; general subscale of explicit attitude F (1, 176) =

1.021, p= .314.

The extremity of affective, cognitive, and general subscales of explicit attitude was analyzed and

the results revealed no significant effects of cognitive resource depletion condition: affective

subscale F (1,176) = .197, p= .658; cognitive subscale F (1,176) = .703, p= .403; general subscale

F (1, 176) = .010, p= .919.

21

H5: Textual information about in vitro meat compared to pictorial information will lead to

more extreme explicit attitudes.

There was non-significant effect of picture/text condition on explicit attitudes F (1, 176) =

3.024, p= .084. The effect of picture/text condition on extremity of explicit attitudes was also

non-significant F (1, 176) = 2.171, p= .142.

The affective, cognitive and general subscales of explicit attitudes were also analyzed but the

results revealed no significant effects of text/picture condition. Affective subscale of explicit

attitudes F (1, 176) = 3.59, p= .060; cognitive subscale F (1, 176) = 1.95, p= .164; general

subscale F (1, 176) = 2.824, p= .095.

When the affective, cognitive and general subscales of explicit attitudes were explored on the

assumption of extremity, the results showed non-significant effects of text/picture condition:

affective subscale F (1, 176) = .553, p= .458; cognitive subscale F (1, 176) = 1.95, p= .164;

general subscale F (1, 176) = .283, p= .596.

H6: Textual information about in vitro meat under conditions of high cognitive recourse will

lead to more extreme explicit attitude than the explicit attitude created by pictorial

information.

No significant interaction effect was observed between the text/picture condition and cognitive

resource depletion condition on explicit attitudes F (1, 176) = .184, p= .669. There was non-

significant interaction effect between the text/picture condition and the cognitive resource

depletion condition on extremity of explicit attitudes F (1, 176) = .076, p= .783.

No significant interaction effects were found between the text/picture condition and cognitive

resource depletion condition on affective subscale of explicit attitudes F (1,176) = .502, p= .479;

cognitive subscale of explicit attitudes F (1, 176) = .004, p= .951; general subscale of explicit

attitudes F (1, 176) = .200. p= .655.

Non-significant interaction effects were found when the affective, cognitive, and general

subscales of explicit attitudes were analyzed: affective subscale F (1, 176) = .434, p= .511;

cognitive subscale F (1, 176) = .004, p= .951; general subscale F (1, 176) = .001, p= .978.

Correlations The results were tested for correlations using Pearson correlation on SPSS. There was

significant relationship found between the implicit and explicit attitudes of respondents (see

Table 4). Affective and general subscale of explicit attitudes was also significantly correlated

with implicit attitudes; only the cognitive subscale was not correlated with implicit attitudes.

Significant relationship was found between the explicit attitudes and each of the subscales.

22

Table 4. Correlations general (Total Participants № 176; per cell)

ST-IAT Explicit attitude

Affective subscale

Cognitive subscale

General subscale

ST-IAT

1 .157* .183* .103 .167*

Explicit attitude

1 .952** .955** .960**

Affective subscale

1 .838** .875**

Cognitive subscale

1 .903**

General subscale

1

*Correlations are significant at the 0.05 level (2-tailed) ** Correlations are significant at the 0.01 level (2-tailed)

The results were divided into the two cognitive depletion conditions and tested for correlations

as well. The results, as can be seen from Table 5, show that in the no cognitive depletion

condition only the general subscale of explicit attitudes is significantly related with implicit

attitudes. In the cognitive depletion condition, neither of the explicit attitudes nor any of the

subscales was significantly related with implicit attitudes.

Table 5. Correlations cognitive depletion condition (Participants № 176)

IAT Explicit attitude

Affective subscale

Cognitive subscale

General subscale

No cognitive

ST-IAT

1 .199 .204 .156 .218*

depletion Explicit attitude

88 1 .952** .952** .969**

Affective subscale

88 88 1 .827** .895**

Cognitive subscale

88 88 88 1 .907**

General subscale

88 88 88 88 1

Cognitive depletion

ST-IAT

1 .122 .160 .043 .113

Explicit attitude

88 1 .952** .960** .951**

Affective subscale

88 88 1 .852** .853**

Cognitive subscale

88 88 88 1 .899**

General subscale

88 88 88 88 1

*Correlations are significant at the 0.05 level (2-tailed) ** Correlations are significant at the 0.01 level (2-tailed)

23

Discussion

The aim of this study was to understand how consumers form their implicit and explicit

attitudes toward unknown attitude objects such as in vitro meat. Pictorial and textual

representations were compared in order to reveal which attitude formation will be triggered.

The study revealed that consumers with low cognitive resources in comparison to those with

high cognitive resources did not form more extreme implicit attitudes as expected. Consumers,

that are not able to scrutinize the information carefully, did not form implicit attitudes or more

extreme implicit attitudes toward unknown object as in vitro meat. The presence of cues, such

as pictorial information about in vitro meat, did not lead to the formation of more extreme

implicit attitudes. The combination of pictorial information as cue and low cognitive resources

did not have such extreme influence on implicit attitudes. When consumers form their implicit

attitude towards unknown object, in this case in vitro meat, the low cognitive resources and

cues such as pictorial information does not lead to more extreme implicit attitudes.

Consumers with high cognitive resources in comparison to those with low cognitive resources

also did not form more extreme explicit attitudes towards unknown object as in vitro meat. The

textual information about in vitro meat which was represented by words associated with in

vitro meat, did not lead to the formation of more extreme explicit attitude. Consumers, that are

capable to think about the information, were not influenced by the words about in vitro meat

when forming their explicit attitudes. These results did not support the hypotheses about

explicit attitudes in this study.

The results revealed that pictorial or textual information cannot trigger the formation of

implicit or explicit attitudes toward unknown attitude object. This may have something to do

with the fact that attitudes are learned, global evaluations of an object (Fazio, 1995). People are

not able to form attitudes towards unknown product without having experience with it and the

time and motivation to carefully scrutinize the information about it. Even the formation of

implicit attitudes would require previous experience with the product on which the automatic,

unconscious favourable or unfavourable evaluation is based. The presence of pictures or words

about in vitro meat is not sufficient to start the attitude formation process.

Past experience does influence the processing of current information (Smith & DeCoster, 2000)

and people do not have any previous experience with in vitro meat. The knowledge that in vitro

meat words provide could be insufficient to understand and form a mental model of in vitro

meat (Schnotz, 2002). Consumers have never seen in vitro meat or a by-product and some have

not even heard about it. Some authors suggest that presenting respondents with photographs

rather than with real object is likely to reduce the vividness of the option (Shiv & Fedorikhin,

1999; Moore, 1973; Loewenstein, 1996). People process the information in a quick, effortless

manner unless they have the ability and motivation to perform more extensive, effortful

thinking (Petty & Cacioppo, 1986). Presenting people with pictures of in vitro meat reduces the

vividness of the product which undermines the attitude formation towards in vitro meat. The

pictures are not able to provide sufficient knowledge about in vitro meat, thus, people are not

able to categorize the object and make inferences of the object’s features (Miller et al., 2005).

24

Implicit and explicit attitudes are governed by separate mental systems and stored in different

areas of the brain (DeCoster, 2006). Therefore, people could hold both implicit and explicit

attitudes of different valence towards the same attitude object. However, significant

relationship effect was found between implicit and explicit attitudes which show that after all

they are interconnected. Both represent the associations between the object and the summary

evaluation of the same object (Fazio, 1995).

Implicit and explicit attitudes were also tested for significant correlation divided into the

cognitive depletion groups. There was no relationship between implicit and explicit attitudes

under conditions of low and high cognitive resources. This could mean that the implicit

attitudes do not depend on the explicit attitudes and vice versa under low and high cognitive

resources.

However, the cognitive resource depletion task, that provided the control for low and high

cognitive resources of participants, proved to be successful. The participants in the condition

that had to write a text on favourite topic without using the letters ‘a’ and ‘n’, reported being

tired immediately after the writing task. This means that when they were answering the ST-IAT

questions and the explicit attitude questions, their cognitive resources were in fact low. While

the participants in the other conditions that were writing a text without the letters ‘x’ and ‘z’ did

find the task a lot easier and reported not being tired immediately after it. However, this effect

of tiredness in the first condition decayed with time. The participants reported that although

being tired immediately after the writing task, they were not feeling tired in the later stages of

the experiment. To sum up, the participants in the cognitive resource depletion condition

reported being more tired than those in no depletion condition. However, the strength of the

depletion effect, in general, could be considered more as average than strong. Also the feeling of

tiredness decayed with time. This could be due to the time they had to recover during the ST-

IAT task and explicit attitudes questionnaire. This decay might be overcome with the

introduction of another cognitive depletion task before the explicit attitude questionnaire

would refresh the feeling of tiredness.

The participants were asked additional questions about their gender, age, prior knowledge of in

vitro meat. There was no gender effect on explicit attitudes or any of the affective, cognitive, or

general subscales of explicit attitudes. However, significant gender effect was found on implicit,

automatic attitudes.

The age of the participants did not influence the implicit attitudes towards unknown attitude

object but was significant on explicit attitudes and the affective, cognitive and general subscales

of explicit attitudes. The participants were between 17 and 34 years old. Young people aged

between 18 and 23 were more neutral in their explicit attitudes toward in vitro meat. People

between 27 and 31 years of age showed a lot more negative explicit attitude than the rest of the

participants. However, this study was not designed to explain the differences in the

demographic variables about implicit and explicit attitudes. It would probably be interesting to

investigate these differences in further research.

Some of the respondents reported having prior knowledge about in vitro meat. The results

showed that this was significant for the explicit attitudes and the affective, cognitive and general

subscales of explicit attitudes. For the participants that were able to scrutinize the information

carefully, being more familiar with in vitro meat resulted in more positive explicit attitude.

These participants were able to categorize and infer about the product more effortlessly (Miller

25

et al, 2005). Prior knowledge of in vitro meat had no influence on the implicit attitude measures.

This is probably because implicit attitude is automatic, unconscious process which is activated

when people encounter the attitude object (Wilson et al., 2000). Therefore, it does not

necessarily require previous knowledge about the attitude object.

To sum up, consumers with low cognitive resources do not form more extreme implicit attitude

than those with high cognitive resources. Consumers with high cognitive resources in

comparison to those with low cognitive resources also do not form more extreme explicit

attitudes towards unknown object as in vitro meat. Textual information in comparison to

pictorial information proved to have more positive influence on both implicit and explicit

attitudes. Implicit and explicit attitudes proved to be interconnected, although, being govern by

separate mental systems.

26

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29

Appendix A

Table 1 Words

Words with positive and negative valence:

Valence Words Results Mean

Positive freedom vrijheid 6.33

peace vrede 6.53

pleasure plezier 5.87

friend vriend 6.47

health gezondheid 6.67

Negative tragedy tragedie 1.80

abuse misbruik 1.53

sickness ziekte 2.07

murder moord 1.27

death dood 1.80

In vitro meat words:

Results Mean

muscle stem cell stancel 5.60

tissue culture weefselkweek 4.60

laboratory-grown laboratotium 6.13

cultured burger kweekburger 4.53

cultured steak kweeksteak 3.20

30

Table 2 Pictures

Pictures with positive valence:

Thumb up Smile

Sunset Beach

Rainbow

Pictures Results Mean

Thumb up 5.67

Smile 5.73

Sunset 5.87

Beach 6.07

Rainbow 6.00

31

Pictures with negative valence:

Poverty Sad

Cancer Crying

Car crash

Pictures Results Mean

Poverty 1.53

Sad 2.40

Cancer 1.73

Crying 1.60

Car crash 1.80

32

In vitro meat pictures:

Laboratory-grown Tissue culture

Cultured burger Cultured steak

Muscle stem cell

Pictures Results Mean

Laboratory-grown 6.13

Tissue culture 4.60

Cultured burger 4.53

Cultured steak 4.80

Muscle stem cell 5.60

33

Appendix B

Explicit attitude question

Geef op de onderstaande schaal uw reactie ten opzichte van kweekvlees (....)

Affective scale

1=hatelijk(hateful) 7=hartelijk(love)

1=verdriet(sad) 7=blijdschap(delighted)

1=ontevreden(annoyed) 7=tevreden(happy)

1=verveeld(bored) 7=opgewonden(excited)

1=gespannen(angry) 7=ontspannen(relaxed)

1=afwijzing(disgusted) 7=acceptatie(acceptance)

1=bedroefd(sorrow) 7=vreugde(joy)

Cognitive scale

1=nutteloos(useless) 7=nuttig(useful)

1=onverstandig(foolish) 7=verstandig(wise)

1=onveilig(unsafe) 7=veilig(safe)

1=schadelijk(harmful) 7=ten goede komend(beneficial)

1=waardeloos(worthless) 7=waardevol(valuable)

1=onvolmaakt(imperfect) 7=volmaakt(perfect)

1=ongezond(unhealthy) 7=gezond(wholsome)

General

1=negatief(negative) 7=positief(positive)

1=onprettig(dislike) 7=prettig(like)

1=slecht(bad) 7=goed(good)

1=onwenselijk(undesirable) 7=wenselijk(desirable)

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Questions for picture-word association

1. Please indicate the extent to which you associate the picture with ‘cultured steak’:

1 – 2 – 3 – 4 – 5 – 6 – 7

Not at all related Strongly related

2. Please indicate the extent to which you associate the picture with ‘laboratory-grown’:

1 – 2 – 3 – 4 – 5 – 6 – 7

Not at all related Strongly related

3. Please indicate the extent to which you associate the picture with ‘muscle stem cell’:

1 – 2 – 3 – 4 – 5 – 6 – 7

Not at all related Strongly related

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4. Please indicate the extent to which you associate the picture with ‘cultured burger’:

1 – 2 – 3 – 4 – 5 – 6 – 7

Not at all related Strongly related

5. Please indicate the extent to which you associate the picture with ‘tissue culture’:

1 – 2 – 3 – 4 – 5 – 6 – 7

Not at all related Strongly related