The somatic marker affecting decisional processes in obsessive-compulsive disorder
-
Upload
humanitas-research -
Category
Documents
-
view
3 -
download
0
Transcript of The somatic marker affecting decisional processes in obsessive-compulsive disorder
This article was downloaded by: [Rafael Freire]On: 19 October 2011, At: 05:28Publisher: Psychology PressInforma Ltd Registered in England and Wales Registered Number: 1072954 Registeredoffice: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Cognitive NeuropsychiatryPublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/pcnp20
The somatic marker affectingdecisional processes in obsessive-compulsive disorderPaolo Cavedini a , Claudia Zorzi a , Clementina Baraldi a , SaraPatrini a , Giuliana Salomoni a , Laura Bellodi b , Rafael C.Freire c & Giampaolo Perna aa Department of Clinical Neurosciences, Villa San BenedettoHospital, Hermanas Hospitalarias, Albese con Cassano, Italyb Department of Clinical Neurosciences, San Raffaele ScientificInstitute & Vita-Salute San Raffaele University, School ofPsychology, Milan, Italyc Laboratory of Panic and Respiration, Institute of Psychiatry,Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
Available online: 12 Oct 2011
To cite this article: Paolo Cavedini, Claudia Zorzi, Clementina Baraldi, Sara Patrini, GiulianaSalomoni, Laura Bellodi, Rafael C. Freire & Giampaolo Perna (2011): The somatic markeraffecting decisional processes in obsessive-compulsive disorder, Cognitive Neuropsychiatry,DOI:10.1080/13546805.2011.614152
To link to this article: http://dx.doi.org/10.1080/13546805.2011.614152
PLEASE SCROLL DOWN FOR ARTICLE
Full terms and conditions of use: http://www.tandfonline.com/page/terms-and-conditions
This article may be used for research, teaching, and private study purposes. Anysubstantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,systematic supply, or distribution in any form to anyone is expressly forbidden.
The publisher does not give any warranty express or implied or make anyrepresentation that the contents will be complete or accurate or up to date. Theaccuracy of any instructions, formulae, and drug doses should be independentlyverified with primary sources. The publisher shall not be liable for any loss, actions,
claims, proceedings, demand, or costs or damages whatsoever or howsoever causedarising directly or indirectly in connection with or arising out of the use of thismaterial.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
The somatic marker affecting decisional processes in
obsessive-compulsive disorder
Paolo Cavedini1, Claudia Zorzi1, Clementina Baraldi1,Sara Patrini1, Giuliana Salomoni1, Laura Bellodi2,Rafael C. Freire3, and Giampaolo Perna1
1Department of Clinical Neurosciences, Villa San Benedetto Hospital,
Hermanas Hospitalarias, Albese con Cassano, Italy2Department of Clinical Neurosciences, San Raffaele Scientific
Institute & Vita-Salute San Raffaele University, School of Psychology,
Milan, Italy3Laboratory of Panic and Respiration, Institute of Psychiatry, Federal
University of Rio de Janeiro, Rio de Janeiro, Brazil
Introduction. Patients with obsessive-compulsive disorder (OCD) demonstrateimpairment in decisional processes in which both cognition and emotion play acrucial role.Methods. We investigated the connection between decision-making performancesand choice-related skin conductance responses (SCRs), to identify a somaticmarker impairment affecting decisional processes in these patients. We exploredSCRs during the Iowa Gambling Task in 20 OCD and 18 control, measuringanticipatory and posticipatory psychophysiological reactions according to cardchoices and to the outcomes of each selection.Results. Most patients exhibited weaker SCRs compared to HC, although thereweren’t substantial differences in magnitude between the two groups. In contrastwith HC, patients with OCD showed no significant differences of SCRs activationaccording to card selections; they chose cards from neither favourable norunfavourable decks.Conclusions. The main finding of the study were the evidence of a dysfunctionalbiological marker in OCD subjects, affecting decision-making process. Dysfunc-tional patterns of SCRs could partially explain OCDs’ impairment in this ability.Decision-making deficits in OCDs could be influenced in part by the lack ofsomatic differences in discriminating between advantageous and disadvantageousbehaviour. These findings could lead to a more complete understanding of OCD.
Correspondence should be addressed to Paolo Cavedini, Department of Clinical
Neuroscience, Villa San Benedetto Hospital, Via Roma, 16-22032 Albese con Cassano, Italy.
Email: [email protected]
COGNITIVE NEUROPSYCHIATRY
2011, 1�14, iFirst
# 2011 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business
http://www.psypress.com/cogneuropsychiatry http://dx.doi.org/10.1080/13546805.2011.614152
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
Keywords: Decision making; Obsessive-compulsive disorder; Skin conductance
response; Somatic marker.
INTRODUCTION
Many studies demonstrated impairment in executive functions in obsessive-
compulsive disorder (OCD; Olley, Malhi, & Sachev, 2007). Although
memory functioning may be affected in OCDs, these deficits appear
secondary to an executive failure of organisational strategies during
encoding (Kim, Park, Shin, & Kwon, 2002). On tasks of set shifting,
functioning OCD patients showed increased response latencies, persevera-
tion of responses, and difficulties utilising feedback to adapt to change
(Aycicegi, Dinn, Harris, & Erkmen, 2003). Data in literature also
suggest deficit in planning and problem-solving functions in these patients
(Cavallaro et al., 2003). Recent studies on OCD and related spectrum
disorders (i.e., anorexia nervosa and pathological gambling) highlighted an
impairment in decision-making tasks, suggesting that these patients were
guided by short-term rewards in spite of possible negative consequences that
may occur in the future (Cavedini, Bassi, Ubbiali, et al., 2004; Cavedini,
Riboldi, Keller, D’Annucci, & Bellodi, 2002). With the increasing interest in
the neurobiology of decision making, many researchers suggest that
considering OCD as a disorder of decision making will lead to new research
approaches and novel strategies for drug and behavioural treatments
(Cavedini, Gorini, & Bellodi, 2006).
It is well known that according to the Somatic Marker Hypothesis
(Damasio, 1994), a somatic marker guides human behaviour towards
advantageous decisions. In particular, in decision-making processes, the
activation of a somatic state previously paired with complex stimuli from
the environment, engages preferential signals that mark the different possible
options with different values, thus guiding the subject towards the correct
decision. Thus, this somatic marker curtails the decision-making process,
which would otherwise depend on a slow and demanding cost�benefit
analysis of the various possible choices that could override processing skills
and not allow for a quick and appropriate decision. Data from neuropsy-
chology and neuroimaging studies have shown that the ability to make
advantageous real-life decisions involving choices between actions leading to
uncertain outcomes and the ability to calibrate between reward and
punishment depends upon the integrity of the ventromedial prefrontal
cortex and its interconnected circuits, including the basal ganglia, thalamus,
and amygdala (Bechara, Damasio, Tranel, & Anderson, 1998; Bechara &
Martin, 2004; Bechara, Tranel, & Damasio, 2000; Chamberlain, Blackwell,
Fineberg, Robbins, & Sahakian, 2005; van den Heuvel et al., 2005).
2 CAVEDINI ET AL.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
Moreover, previous research on neurologic patients with lesions in the
ventromedial prefrontal cortex has linked decision-making deficits to the
somatic state of these subjects (Bechara, Damasio, Damasio, & Lee, 1999;
Bechara & Martin, 2004) showing that a severe impairment in the somatic
marker was responsible for decision-making deficits. Risk taking in decision-making tests, such as the Iowa Gambling Task (IGT; Bechara, Damasio,
Damasio, & Anderson, 1994) has been accompanied by a reduced ability to
generate skin conductance responses (SCR) prior to choosing a card from
high-risk decks or in response to punishment (Bechara, Tranel, & Damasio,
2002; Suzuki, Hirota, Takasawa, & Shigemasu, 2003), thus supporting the
hypothesis that automatic signals provide useful information to guide
decision making. More recently, an association between impaired decision-
making ability and a decreased autonomic response was also found inpsychiatric patients (Tchanturia et al., 2007).
A recent study investigated the performance and the SCR in OCD
patients and healthy controls during two cognitive tasks, investigating risk
and ambiguous decisions (Starcke, Tuschen-Caffier, Markowitsch, & Brand,
2009). In the first one (Game of Dice Task*GDT; Brand et al., 2004), there
were no differences in the performance of OCD and healthy subjects; in the
second one (IGT), OCD patients performed poorly, compared to healthy
subjects. In the GDT there were no significant differences in the SCRbetween the two groups, whereas in the IGT the normal controls had higher
SCR compared to OCD patients (Starcke et al., 2009). Consequently, it is
reasonable to hypothesise the existence of a relationship between decision-
making impairment in OCD patients and their somatic state at the moment
of ambiguous decisions (i.e., skin conductance responses), since the brain
structures involved in decision making are also involved in the pathogenesis
of OCD (Mataix-Cols et al., 2004).
The aim of this study was to investigate if the somatic marker is impairedin OCD patients and if it affects the decisional processes in a cognitive task
such as IGT. Specifically, we hypothesise deficits in decision making function
in OCDs compared to healthy controls, confirming data from previous OCD
studies (Cavedini, Riboldi, D’Annucci, et al., 2002); then we expect that
these deficits could be in part explained by different patterns of SCRs
activation in the samples.
METHODS
Sample
The sample consisted of 38 subjects divided into 20 patients with OCD
(13 males, seven females, mean age 36.05911.05 years) and 18 healthy
control subjects (HC) (13 males, five females, mean age 2794.73 years). Two
THE SOMATIC MARKER IN OCD 3
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
subjects recruited for the HC group were excluded for technical problems
during SCR recording.
Patients with OCD were recruited consecutively among those referred to
the Centre for Obsessive-Compulsive Spectrum Disorders at the Department
of Clinical Neuroscience, San Raffaele Hospital, Milan. The HC group wasrecruited among the administrative and worker staff of the Hospital and by
local advertisements for college students. The inclusion criteria in the patient
group was the diagnosis of OCD according to the DSM IV-TR (American
Psychiatric Association, 2000) without other lifetime Axis I diagnosis. HC
who met DSM-IV criteria for any lifetime psychiatric diagnosis were not
included in this study. In addition, subjects with history of substance abuse/
dependency or neurological diseases such as intellectual impairment,
dementia or brain injury were not included also. OCD patients were drugfree for at least 1 month.
This study was approved by an appropriate ethical committee and was
carried out in accordance with ethical principles for the medical community
regarding human experimentation, reported in the latest version of the
Declaration of Helsinki. All subjects provided written informed consent to
the study after the nature of the procedures were accurately explained.
Clinical assessment
Consensus diagnoses were obtained by two senior psychiatrists who
independently assessed the subjects by clinical interview and the MINI
International Neuropsychiatry Interview�Plus (Sheehan et al., 1998). To
evaluate OCD symptoms severity, the Yale-Brown Obsessive-Compulsive
Scale (Y-BOCS; Goodman et al., 1989) was administered.
Neuropsychological assessment
OCD patients and HC were assessed with the Iowa Gambling Task (IGT)
administered by a trained psychologist in a single session. All participants
completed the test without any cooperation or weariness problems. In the
IGT the subject must make 100 card selections from four decks (‘‘A’’, ‘‘B’’,
‘‘C’’, and ‘‘D’’) and the objective is the maximum profit. At the beginning ofthe test the subjects receive a loan of play-money. After turning over each
card, subjects are either given money or asked to pay a penalty according to
a programmed schedule of reward and punishment. Gains and losses are
different for each deck. Decks A and B (‘‘disadvantageous’’ decks) are high
paying but disadvantageous in the long run, because the penalties are even
higher. Decks C and D (‘‘advantageous’’ decks), on the other hand, are low
4 CAVEDINI ET AL.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
paying but advantageous because the penalties are lower, resulting in an
overall gain in the long run.
Neurophysiologic data recording
The participants performed the IGT computerised version, sitting in front
of a computer screen in a quiet and comfortable room. During the test,
subjects had to push a button on a four-button platform in order to choose
a card while their SCRs were registered continuously by two electrodes
attached to the tenar and hypotenar areas on their palms of nondominant
hand. Every time the subject selected a card by clicking a button, a mark
appeared in the wave of SCRs, so that was possible to identify the specific
card picked up from a specific deck and the associated SCRs generated
before and after the selection. We extrapolated from the SCR polygram the
following situations:
. Anticipatory SCRs, characterised by a time window of 5 s before the
selection of each card. In the analysis this SCRs were divided intoadvantageous and disadvantageous SCRs according to card selections
from C and D decks and A and B decks, respectively.
. Posticipatory SCRs, characterised by a time window of 5 s after the card
selection and also divided into advantageous and disadvantageous
SCRs with the same criterion.
. Reward SCRs and punishment SCRs were also subdivided, as char-
acterised by a time window of 5 s after selecting a card giving only a
reward (without penalty) and after selecting a card with a gain followedby a loss.
The intertrial interval was set in 10 s, so that was impossible for the
subject to choose a new card during the refractory period. The data was
collected with a MP150WS system (BIOPAC System) and then analysed by
software able to quantify the SCRs’ variations with mathematical transfor-
mations (AcqKnowledge III). The first step in data analysis was the
calculation of the ‘‘difference’’, a mathematical transformation necessary
to eliminate the down drift in the SCR wave. This function works out the
difference in amplitude of two sample points separated by 100 samples. The
second step is represented by the measurement of the ‘‘area under the curve’’
of the temporal window. This measurement is similar to an integral, except
for the baseline that in this case is drawn between the endpoints of the
selected area. The unit of measurement of the ‘‘area under the curve’’ is
expressed by ms/s.
THE SOMATIC MARKER IN OCD 5
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
Statistical analysis
Due to the nonnormal distribution of variables, nonparametric tests were
also used to analyse the data.
Data from the IGT performance was examined first by comparing the
differences between the total number of advantageous cards minus the total
number of disadvantageous cards selected (net score) by the two groups
(HC vs. OCD) and, second, by analysing the net score in successive blocks of
20 cards each (Bechara, Damasio, Damasio, & Lee, 1999).
One-way analysis of variance (ANOVA) was used to compare age and
education differences between HC and OCD, and the Chi-square test was
used to investigate differences in gender between the two groups.
The Mann�Whitney U-Test was used to compare the intergroup
difference in the amplitude of anticipatory and posticipatory SCRs, before
and after advantageous and disadvantageous decks, between OCD and HC.
The same analysis was used to compare the intergroup difference in the
amplitude of posticipatory SCRs after the choice from decks yielding a
reward (win) or a reward followed by a punishment (win plus loss) between
OCD and HC.
Finally, the Spearman Test was used to find potential correlations
between age and IGT performance between groups.
RESULTS
Decision-making performance
Decision-making performance showed that the net score (total number of
advantageous cards minus the total number of disadvantageous cards
selected) was significantly higher for the HC (�28.55929.16) group than
for OCD (�12.6920.24) patients, Z� �3.88, p�.0001. Means and
standard deviations of card selection in successive blocks of 20 are presented
in Table 1.
TABLE 1IGT performance (total number of advantageous minus disadvantageous cards
selected) in OCD and HC during the five consecutive stages of the task
Stages OCD (M9SD) HC (M9SD) p-level Z
Block 1�20 �1,797.6 �6.196.3 .122 �1544
Block 21�40 �2.197.1 4.89�9.3 .038 2073
Block 41�60 �1.398.9 8.699.4 .006 2711
Block 61�80 �3.299.1 1098.3 .0001 3826
Block 81�100 �1.8910.5 11.497.7 .0001 3733
6 CAVEDINI ET AL.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
A significantly different pattern of choices between the two groups was
found from the second block on, with increasing significant differences
between OCD and HC in decision-making strategy during the task.
SCRs analysis
Anticipatory SCRs. Means and standard deviations for anticipatory
SCRs in advantageous and disadvantageous cards selection between OCD
and HC are presented in Table 2. Analyses revealed no difference in the
amplitude of anticipatory SCRs before advantageous, Z�0.248, p�.803,
and disadvantageous, Z� �0.13, p�.895, decks between OCD and HC.
On the other hand, the amplitude of the SCRs was significantly higher
before choosing from disadvantageous decks than from advantageous decks
in the HC group, Z�2.351, p�.018. This difference was not found in the
OCD group, Z�1.502, p�.132. Results are presented in Figure 1.
Posticipatory SCRs. Means and standard deviations for posticipatory
SCRs in advantageous and disadvantageous cards selection between OCD
and HC are presented in Table 2. The HC group and the OCD group did not
significantly differ in the amplitude of activation after advantageous,
Z�0.263, p�.792, and disadvantageous decks, Z�0.628, p�.529. In the
HC group, a significantly higher activation was found after choosing from
disadvantageous than from advantageous decks, Z�3.337, p�.0001. These
differences were not found in the OCD group, where activation after
advantageous, compared with activation after disadvantageous decks, was
not significantly different, Z�1.017, p�.309. Results are presented in
Figure 2.
TABLE 2Means and standard deviations for anticipatory and posticipatory SCRs in
advantageous and disadvantageous cards selection: Comparison between OCDand HC
OCD HC
Adv. decks
(M9SD)
Disadv. decks
(M9SD)
Adv. decks
(M9SD)
Disadv. decks
(M9SD)
Anticipatory
SCRs
0.29090.117 0.30690.114 0.28190.112 0.30490.123
Posticipatory
SCRs
0.27490.112 0.27890.114 0.28790.119 0.30690.123
THE SOMATIC MARKER IN OCD 7
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
Reward and punishment. HC subjects patients show differences in levels
of activation (magnitude of the SCRs) related to receiving rewards or
rewards followed by punishments, Z�2.911, p�.003, but this was not
evident in OCD patients, Z�0.579, p�.563.
Demographics and effect on performance
In OCD patients age at onset was 18.799.3 years, and OCD mean
Y-BOCS total score was 28.395.3. As regard to demographic character-
istics between HC and OCD, we found a significant difference in age,
Z� �3.055, p�.002, but not in years of education (p�.391) and sex
(p�.63). Although there was a significant difference in age between OCD
patients and HC, age was unrelated to IGT performance, T� �0.495,
p�.624
OCDHCGroups
0,20
0,22
0,24
0,26
0,28
0,30
0,32
0,34
0,36
0,38
SC
Rs
(µs/
sec)
Disadv. decks Adv. decks
Figure 1. Anticipatory SCRs in OCD and HC for advantageous and disadvantageous card selection
(error bars represent 5% error).
8 CAVEDINI ET AL.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
DISCUSSION
The main finding of the study was the evidence of a dysfunctional biological
marker in OCD subjects, affecting the decision-making process. Dysfunc-
tional patterns of SCRs could partially explain OCDs impairment in this
ability. In fact, decision-making deficits in OCDs could be influenced in part
by the lack of somatic differences in discriminating between advantageous
and disadvantageous behaviour. In contrast with HC, in fact, OCDs showed
no significant difference of SCRs activation in discriminating advantageous
and disadvantageous behaviours during a decision-making task.
Given the involvement of orbitofrontal cortex functioning in the
pathogenesis of OCD, patients affected by this disorder showed impairment
in decisional processes, as confirmed by many research data (Cavedini, Bassi,
Zorzi, & Bellodi, 2004; Cavedini, Gorini, & Bellodi, 2006; Cavedini, Zorzi,
et al., 2006). Deficit in decision-making function is considered an endophe-
notype marker of OCD, differently from other anxiety disorders (Cavedini,
Riboldi, D’Annucci, et al., 2002).
OCDHC
Groups
0,20
0,22
0,24
0,26
0,28
0,30
0,32
0,34
0,36
0,38
SC
Rs
(µs/
sec)
Disadv. decks Adv. decks
Figure 2. Posticipatory SCRs in OCD and HC for advantageous and disadvantageous card selection
(error bars represent 5% error).
THE SOMATIC MARKER IN OCD 9
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
Then, clinical observation also suggests the presence of decision-making
deficit in OCDs, as well evidenced, for example, in pathological doubting.
Compulsive behaviour can be seen as an alternative way of managing reward
and punishment; these patients in fact seem to prefer short-term rewards
such as compulsions or avoiding behaviours (that momentarily reduce
anxiety and the persistence of obsessions), in spite of actual punishment (i.e.,
increasing of anxiety state caused by obsessions). These pathological
behaviours cause negative consequences in the long run, increasing OCD
symptoms and worsening quality of life.
The IGT, like many real-life situations, represents a complex decisional
situation where a choice must be made in the face of uncertainty and variable
outcomes. A complete and reliable analysis of the various options and of
their consequences would be complicated and effortful; thus, these patients
may tend to make a choice offering immediate and high rewards. In the
context of decision making, the activation of a somatic state that was
previously paired with environmental stimuli engages preferential signals
that mark the different options with different values and thus guides the
subject towards the correct decision. In the current study, patients appeared
to be compromised in decision making, failing to develop any strategy in
their IGT card selection. These data confirmed results of previous studies,
investigating decision making impairment in OCD and in other spectrum
disorders (Cavedini, Bassi, Zorzi, & Bellodi, 2004; Cavedini, Gorini, &
Bellodi, 2006; Cavedini, Zorzi, et al., 2006; Starcke et al., 2009). From a
therapeutic point of view, it is well known that the IGT has been shown to be
sensitive to biological as well as to cognitive aspects of decisional processes
in obsessive-compulsive spectrum disorders. In fact, previous studies have
stressed the role of decision-making functioning in predicting both
antiobsessive treatment outcome with serotonin reuptake inhibitors in
patients with OCD (Cavedini, Bassi, Zorzi, & Bellodi, 2004), and a cognitive
behavioural approach in patients with anorexia nervosa (Cavedini, Zorzi,
et al., 2006).
Starcke’s work evidenced significant differences in SCR activations during
IGT between OCD and HC groups, with a higher activation in the second
one (Starcke et al., 2009). More specifically, in our study, analysing SCR
activation during the decision-making process, an association between
defective decision making and a pattern of both anticipatory- and
posticipatory-reduced SCRs reactivity was demonstrated. However, results
from the intergroup comparison on the amplitude of the somatic activation
reveal that there are no substantial differences in magnitude between HC and
OCD patients, independent of the strategy used or test performance. In
particular, analysis of the anticipatory SCRs revealed a differentiated rate of
10 CAVEDINI ET AL.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
activation according to card selection in the HC, with greater activation
before they chose cards from a disadvantageous deck and weaker activation
before they chose from an advantageous one. OCD patients’ activation
instead did not change significantly whether they choose a card from the
favourable or unfavourable decks. Regarding posticipatory SCRs, our
findings are consistent with previous research in finding a relation between
SCRs and the affective value of stimuli (Bechara et al., 1999; Suzuki et al.,
2003). In the HC group, galvanic response is more elevated after a selection
from a disadvantageous deck and a win, whereas OCD subjects showed no
modulation in their posticipatory responses.
The lack of suitable somatic responses deprives OCD patients of a
mechanism of bypassing a cognitive analysis and guiding them towards
appropriate choices. Without this mechanism, they have more difficulty in
recognising a convenient strategy, and probably they perform the task
answering to short-term contingencies and consequently they fail more often
than healthy controls.
It should be noted that results from this study demonstrate differences
between OCD and HC. Thus, we cannot exclude impaired SCRs not also
being typical for other anxiety disorders, caused by an overall higher level of
anxiety. Anyway, given the present study results, some interesting considera-
tions should be made about clinical and treatment implications for OCD.
The lack of any somatic differences in discriminating between advantageous
versus disadvantageous behaviour as observed in experimental conditions
could help to provide an understanding of pathological behaviour exhibited
by OCD patients. Specifically, a lack of behavioural flexibility (continuous
repetition of the same noxious behaviour), search for an immediate reward
(relief of anxiety from compulsions), and blindness to negative future
consequences (compromised life quality), that are characteristic traits of this
disorder, may be effects of the somatic marker dysfunction in OCD patients.
It’s well known that many studies have conceptualised OCD as a complex
disorder; OCD heterogeneity is evidenced in clinical manifestations,
neurobiological functioning, and different treatment outcomes (de Mathis
et al., 2006; Mataix-Cols, Rosario-Campos, & Leckman, 2005). Moreover,
even if OCD studies highlighted an impairment in decision-making tasks
(Cavallaro et al., 2003; Cavedini, Riboldi, Keller, et al., 2002), a behavioural
heterogeneity was evidenced; a considerable portion of OCD patients in fact
performs decision making in the same way as normal subjects do. Recent
research showed how this heterogeneity divides subjects into different
populations in terms of symptom dimensions (Lawrence et al., 2006) or
treatment response (Cavedini, Bassi, Zorzi, & Bellodi, 2004; Cavedini, Zorzi,
et al., 2006), with bad treatment outcome when decision-making impairment
THE SOMATIC MARKER IN OCD 11
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
is present. Further, the presence of heterogeneous pathogenic mechanisms in
OCD (de Mathis et al., 2006; Mataix-Cols et al., 2005) calls for closer
examination of cognitive and emotional functioning, with research into
decision making as a possible first step. Then, OCD heterogeneity must be
considered for a better understanding of our results, given neurophysiolo-
gical dysfunction in the somatic marker as specific trait of an OCD
subgroup, showing dysfunctional behavioural patterns.
The main limitations of this study were the relatively small sample size
and the nonpaired recruitment of subjects. The age did not interfere in the
IGT scores and probably the differences between the two groups had a small
effect in the current study. Another limit of the work was the lack of state
depression and anxiety measures in evaluating clinical variables of the
samples.
The present study indicated that OCD patients (or an OCD subgroup)
may have a dysfunctional biological marker, and accordingly have an
impaired performance in cognitive tasks. The cause of the biological marker
dysfunction, as well as the determinant of the heterogeneity in OCD patients,
is still unclear and more research is needed in this field.
Manuscript received 28 October 2010
Revised manuscript received 31 May 2011
First published online 13 October 2011
REFERENCES
American Psychiatric Association (2000). Diagnostic and statistical manual of mental disorders
(4th ed., text rev.). Washington, DC: Author.
Aycicegi, A., Dinn, W. M., Harris, C. L., & Erkmen, H. (2003). Neuropsychological function in
obsessive-compulsive disorder: Effects of comorbid conditions on task performance. European
Psychiatry, 18, 241�248.
Bechara, A., Damasio, A. R., Damasio, H., & Anderson, S. W. (1994). Intensitivity to future
consequences following damage to human prefrontal cortex. Cognition, 50, 7�15.
Bechara, A., Damasio, H., Damasio, A. R., & Lee, G. P. (1999). Different contributions of the
human amygdala and ventromedial prefrontal cortex to decision-making. Journal of
Neuroscience, 19, 5473�5481.
Bechara, A., Damasio, H., Tranel, D., & Anderson, S. W. (1998). Dissociation of working memory
from decision making within the human prefrontal cortex. Journal of Neuroscience, 18,
428�437.
Bechara, A., & Martin, E. M. (2004). Impaired decision making related to working memory
deficits in individuals with substance addictions. Neuropsychology, 18, 152�162.
Bechara, A., Tranel, D., & Damasio, H. (2000). Characterization of the decision-making deficit of
patients with ventromedial prefrontal cortex lesions. Brain, 123, 2189�2202.
Bechara, A., Tranel, D., & Damasio, A. R. (2002). The somatic marker hypothesis and decision-
making. In F. Boller & J. Grafman (Eds.), Handbook of neuropsychology: Frontal lobes (2nd ed.,
Vol. 7, pp. 117�143). Amsterdam, The Netherlands: Elsevier.
12 CAVEDINI ET AL.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
Brand, M., Labudda, K., Kalbe, E., Hilker, R., Emmans, D., Fuchs, G., et al. (2004). Decision-
making impairments in patients with Parkinson’s disease. Behavioural Neurology, 15, 77�85.
Cavallaro, R., Cavedini, P., Mistretta, P., Bassi, T., Angelone, S. M., & Ubbiali, A. (2003). Basal-
corticofrontal circuits in schizophrenia and obsessive-compulsive disorder: A controlled,
double dissociation study. Biological Psychiatry, 54, 437�443.
Cavedini, P., Bassi, T., Ubbiali, A., Casolari, A., Giordani, S., & Zorzi, C. (2004). Neuropsycho-
logical investigation of decision-making in anorexia nervosa. Psychiatry Research, 127, 259�266.
Cavedini, P., Bassi, T., Zorzi, C., & Bellodi, L. (2004). The advantages of choosing antiobsessive
therapy according to decision-making functioning. Journal of Clinical Psychopharmacology, 24,
628�631.
Cavedini, P., Gorini, A., & Bellodi, L. (2006). Understanding obsessive-compulsive disorder: Focus
on decision making. Neuropsychology Review, 16, 3�15. Review.
Cavedini, P., Riboldi, G., D’Annucci, A., Belotti, P., Cisima, M., & Bellodi, L. (2002). Decision-
making heterogeneity in obsessive-compulsive disorder: Ventromedial prefrontal cortex
function predicts different treatment outcomes. Neuropsychologia, 40, 205�211.
Cavedini, P., Riboldi, G., Keller, R., D’Annucci, A., & Bellodi, L. (2002). Frontal lobe dysfunction
in pathological gambling patients. Biological Psychiatry, 51, 334�341.
Cavedini, P., Zorzi, C., Bassi, T., Gorini, A., Baraldi, C., Ubbiali, A., & Bellodi, L. (2006).
Decision-making functioning as a predictor of treatment outcome in anorexia nervosa.
Psychiatry Research, 145, 179�187.
Chamberlain, S. R., Blackwell, A. D., Fineberg, N. A., Robbins, T. W., & Sahakian, B. J. (2005).
The neuropsychology of obsessive-compulsive disorder: The importance of failures in cognitive
and behavioral inhibition as candidate endophenotypic markers. Neuroscience of Behavioral
Review, 29, 399�419.
Damasio, A. R. (1994). Descartes’ error: Emotion, reason, and the human brain. New York, NY:
G. P. Putnam’s Sons.
De Mathis, M. A., Diniz, J. B., do Rosario, M. C., Torres, A. R., Hoexter, M., Hasler, G., &
Miguel, E. C. (2006). What is the optimal way to subdivide obsessive-compulsive disorder?
CNS Spectrums, 11, 762�768, 771�774, 776�779. Review.
Goodman, W. K., Price, L. H., Rasmussen, S. A., Mazure, C., Fleischmann, R. L., & Hill, C. L.
(1989). The Yale-Brown Obsessive-Compulsive Scale, I: Development, use and reliability.
Archives of General Psychiatry, 40, 1006�1011.
Kim, M. S., Park, S. J., Shin, M. S., & Kwon, J. S. (2002). Neuropsychological profile in patients
with obsessive-compulsive disorder over a period of 4-month treatment. Journal of Psychiatric
Research, 36, 257�265.
Lawrence, N. S., Wooderson, S., Mataix-Cols, D., David, R., Speckens, A., & Phillips, M. L.
(2006). Decision making and set shifting impairments are associated with distinct symptom
dimensions in obsessive-compulsive disorder. Neuropsychology, 20(4), 409�419.
Mataix-Cols, D., Rosario-Campos, M. C., & Leckman, J. F. (2005). A multidimensional model of
obsessive-compulsive disorder. American Journal of Psychiatry, 162, 228�238. Review.
Mataix-Cols, D., Wooderson, S., Lawrence, N., Brammer, M. J., Speckens, A., & Phillips, M. L.
(2004). Distinct neural correlates of washing, checking, and hoarding symptom dimensions in
obsessive-compulsive disorder. Archives of General Psychiatry, 61, 564�576.
Olley, A., Malhi, G., & Sachev, P. (2007). Memory and executive functioning in obsessive-
compulsive disorder: a selective review. Journal of Affective Disorders, 104, 15�23.
Sheehan, D. V., Lecrubier, Y., Sheehan, K. H., Amorim, P., Janavs, J., Weiller, E., et al. (1998). The
Mini-International Neuropsychiatric Interview (MINI): The development and validation of a
structured diagnostic psychiatric interview for DSM-IV and ICD-10. Journal of Clinical
Psychiatry, 59, 22�33.
THE SOMATIC MARKER IN OCD 13
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011
Starcke, K., Tuschen-Caffier, B., Markowitsch, H. J., & Brand, M. (2009). Skin conductance
responses during decisions in ambiguous and risky situations in obsessive-compulsive disorder.
Cognitive Neuropsychiatry, 14, 199�216.
Suzuki, A., Hirota, A., Takasawa, N., & Shigemasu, K. (2003). Application of the somatic marker
hypothesis to individual differences in decision making. Biological Psychology, 65, 81�88.
Tchanturia, K., Liao, P. C., Uher, R., Lawrence, N., Treasure, J., & Campbell, I. C. (2007). An
investigation of decision making in anorexia nervosa using the Iowa Gambling Task and skin
conductance measurements. Journal of International Neuropsychological Society, 13, 635�641.
Van den Heuvel, O. A., Veltman, D. J., Groenewegen, H. J., Cath, D. C., van Balkom, A. J. L. M.,
& van Hartskamp, J. (2005). Frontal-striatal dysfunction during planning in obsessive-
compulsive disorder. Archives of General Psychiatry, 62, 301�309.
14 CAVEDINI ET AL.
Dow
nloa
ded
by [
Raf
ael F
reir
e] a
t 05:
28 1
9 O
ctob
er 2
011