Neuroimaging Correlates of Traumatic Brain Injury and Suicidal Behavior
Relapse Risk in Substance Abuse Disorders Pre- Determined by Psychoshysiology Functional...
Transcript of Relapse Risk in Substance Abuse Disorders Pre- Determined by Psychoshysiology Functional...
Running Head: PSYCHOPHYSIOLOGY AND NEUROIMAGING PREDICT RELAPSE 1
qEEG and fMRI Predict Relapse Risk in Abstinent Substance
Abusers: Scaled Use is Advocated
Eric Ternand
University of Minnesota
PSYCHOPHYSIOLOGY AND NEUROIMAGING PREDICT RELAPSE 2
Abstract
Alcohol and other substance use disorders (SUDs) destroy the
lives of millions of people and cost society billions of dollars
every year. And yet after decades of intense and well-funded
research, the major goals of elucidating a definitive etiology,
finding effective treatments, or even just predicting the course
of the disease in any given individual remain frustratingly
elusive. It’s estimated that a third of the chemically-dependent,
treatment-seeking population will relapse immediately following
treatment completion (many for the 5th or 6th time), and that
statistic has not changed in nearly 40 years (Emrick, 1974;
Miller, Walters, & Bennet, 2001).
The purpose of this review is to demonstrate that there are
tools available to screen for relapsing subtype substance users
before they enter treatment. Further, it will be shown that this
can be done reliably and inexpensively through
psychophysiological testing (qEEG elevated fast-β and/or
reduced/delayed P300 ERP) and/or functional neuroimaging
(specifically BOLD fMRI targeting the orbital and medial
prefrontal cortex during either go-no-go or drug-cue tasks).
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Finally I put forth an argument that doing so would enable a
cost savings by treating those most in need most thoroughly,
giving more intensive Tx to the relapse-prone subtype, while
simultaneously shifting the majority of treatment seekers, the
non-relapsers, out of the traditional (and expensive) inpatient
treatment centers. They don’t want to be there, and the research
consistently shows they don’t need to be (Bottlender & Soyka,
2005) so why not use those resources on the real problem?
This would free up resources to finally reclaim that long
lost third, and also open up exciting new possibilities for the
next step forward as well.
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Alcoholism abuse and dependence, and other substance use
disorders (SUDs) are devastating diseases with enormous costs for
society and for afflicted individuals and their loved ones. It is
conservatively estimated that alcohol (EtOH) abuse alone cost:
“$43,000,000,000 annually in lost production, medical and public
assistance expenditures, police and court costs, and motor
vehicle and other accidents” (109th Congress of the United
States, 2005) just in the United States. It is further estimated
that approximately 7% of the adult population of the country are
abusers of alcohol or alcohol dependent based on DSM-IV
definitions- (Congress, 2005). More than 30% of the automobile
accident fatalities in this country involve alcohol in some
fashion, and perhaps most tragically, more than half of kids
killed in car accidents (910 of them last year) involved parental
intoxication (Insurance Institute for Highway Safety [IIHS],
2012). While clearly the economic toll of this disease is
staggering, the human costs are far greater.
Children of chemically dependent parents are nine times more
likely to end up in prison, and are 13 times more likely to get
pregnant before the age of 18 (Congress, 2005). At least 49% of
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domestic abuse cases involve alcohol or other drug use (Congress,
2005). Those who have ever had a diagnosed SUD are 15 times more
likely to be in jail or on probation at some point, and are 27
times more likely to commit suicide than their non-substance-
abusing peers (Congress, 2005). The effects of this dependency
syndrome are wide ranging and extremely destructive, and while
advances in understanding SUD causation and treatment have indeed
occurred (Miller, Walters, & Bennett, 2001), it remains a disease
in many cases almost defined by its chronic relapses and
revolving door treatment centers.
Miller, Walters, & Bennet (2001) analyzed seven large,
multi-site studies of alcoholism treatment (ntotal =8,389) for
efficacy, all of which included intensive and long-term
longitudinal follow-up (a feature lacking in many of the self-
conducted “studies” of efficacy performed and promoted by
treatment providers). Though the metrics are variable and the
definitional questions continue to nag (when has a “relapse”
occurred? Should drinking days or drinks per drinking day be the
primary determinant of “non-abstinent improvers?”), the final
conclusion reached is that about one third of those exiting
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primary alcoholism treatment remain abstinent a year after
discharge, while another third show “substantial improvement.”
This is substantially unchanged from a similar study done in the
early 1970s (Emrick, 1974) which literally reported exactly the
same proportions almost 30 years prior.
In the intervening four decades it is essentially impossible
to overstate the amount of time, effort, money, and brain power
thrown at the problem of better understanding SUDs and of more
effectively treating the victims thereof. The NIH’s “Research
Portfolio Online Reporting Tools (RePORT)” shows that the Federal
Government alone, has spent somewhere between $5 and $10 billion
on SUD research and treatment annually over the last 5 years; a
rate which is extremely sizable in the research world, and has
held stable and even seen increases in relative, inflation-
adjusted terms for many years (National Institutes of Health
[NIH], 2012). All of that money spent on such research and
clinical treatment also translates into tens or hundreds of
thousands of scientists and clinicians devoting their
professional lives to solving this problem. And yet for all of
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this effort and all of this money over 40 years, a third of
patients still chronically relapse.
Certainly progress has been made in a number of areas, and
by no means is research into alcoholism a black hole or waste of
resources. There have been great strides in casting light on an
incredibly elusive etiology and doing the basic research that
will ultimately lead to better outcomes for all patients.
Advances in genetics, genomics, neuroscience, and brain-imaging,
psychopharmacology, and physiology, all show promise for altering
the decades old treatment paradigm and ultimately overcoming this
problem of chronic relapse and addressing the issue of that
stubborn, forsaken, final third.
If it is possible to predict, a priori, which treatment-
seeking addicts are most likely to relapse, then it should also
be possible to devote to that group the most significant
resources and effect a better outcome than the difficult
prognosis the relapse-prone third now faces. It should also be
possible to pre-determine individualized treatment options, and
apply scarce resources more efficiently – devoting the most
expensive, longest lasting interventions to those most in need of
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them and utilizing more efficient, outpatient-type treatment for
those likely to obtain significant benefit from any intervention
(Bottlender and Soyka, 2005 showed that for non-chronic-relapsing
AUD patients, inpatient vs. outpatient was not correlated to
outcome at all. This finding has shown up over and over again
throughout the literature).
It may also be the case that different subtypes of SUDs can
be identified, each responding optimally to different treatments.
The ideal situation would be simple, inexpensive, and
determinative pre-treatment testing that would give practitioners
insights into what would work best for any given patient, much as
we would culture an infection to know which antibiotic to
prescribe, or biopsy and genotype a tumor before deciding on
radiation vs. chemotherapy vs. surgery. This review will
demonstrate that we are very close to that style of treatment for
SUDs.
Predictors of Relapse
Traditional Psychological Metrics- Demographic, Behavioral,
Personality-Based, Etc.
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Craving. The word itself almost makes one think addiction.
And the research literature is littered with references to this
somewhat ephemeral concept. But it turns out that years ago,
decades even, no one could really agree on an operational
definition and that none of the definitions put forward seemed
to have predictive validity anyway (Stanovich, 2010; Ciraulo,
Piechniczek-Buczek & Iscan, 2003). Defining craving as (self-
reported) drug-cue reactivity in 1994, Rohsenow et al. observed
no significant effect (a negative result) when they tried to
correlate feelings of “craving” upon seeing drug-cued stimuli
(pictures of bottles, or needles, etc… as appropriate to the
individual) with later relapse risk. Defining craving via self-
reported “urge diaries” also consistently lead to non-results and
frustrating refutations of the obvious face validity craving
seemed to enjoy (Miller & Gold, 1990, among others). Even when
formally operationalized with a questionnaire, as for example by
Miller et al. in 1996, the correlation with relapse was barely
significant and the effect size miniscule. And despite the fact
that these studies – showing no significant link between
“craving” (however defined) and relapse risk, treatment outcome,
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or any other metric – were completed 20+ years ago in some cases,
the term continues to pepper the literature (to be sure not all
the craving studies have led nowhere, but an overwhelming
majority “…fail to demonstrate significance”).
This is true actually of more than just craving; other
metrics like disease onset/age of first drink, socio-economic
status, marital status, age at treatment entrance, education
level, and even gender show very inconsistent results in terms of
predicting relapse (Porjesz et al., 2005. Walton et al., 2003;
Durazzo et al., 2008).
There are a number of factors that have long been thought to
predict outcomes in substance use disorder patients that can
usually be obtained on simple medical history forms, with
interviews, or with various psychological assessment instruments.
Co-morbid psychiatric illness, for example, is widely believed to
have a strong correlation with relapse risk, and this has to a
certain extent been borne out in the literature (notably by
Ciralao, 2003; Durazzo, 2008), but again, it varies considerably
from study to study.
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For example, Cadoret and Winkour (1974) found that
depression symptoms increased risk of relapse in men, but were
actually protective for female subjects, lowering their risk of
relapse. Rounsaville et al. (1987) found exactly the opposite to
be true; depression protected men and caused relapse in women!
Heath et al., in two separate studies (1997 & 2001) found that
both depression and anxiety histories predicted poor treatment
outcomes, while Kushner (2005) found that neither had any effect
and Brown (1990) showed that anxiety did not correlate with
outcomes. In sum it seems that it cannot be reliably stated
whether or not co-morbid “minor” psychopathology (mood and
anxiety disorders) can predict treatment outcome with any
accuracy or reliability (Ciralao, 2003).
It seems obvious that at the very least PTSD and bi-polar
disease should be predictive of relapse, but the literature here
is just as unclear (Kushner et al., 2005; Ouimette, Brown &
Najavits, 1998). This seems to be another example of face
validity being confused with empirical predictive validity - a
stumbling block social scientists must constantly be watching out
for (Stanovich, 2010).
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Some of the traditional metrics do “work” at predicting
relapse, to a limited degree, and have held up well under
rigorous study. These include severity of disease (directly correlated
with relapse-risk and severity of relapse - Heath et al., 1997;
Poling, Kosten & Sofuoglu, 2007; Bauer, 2012), family history of SUDs
(Milne et al., 2009), self-efficacy (definitely inversely correlated
with relapse risk, but causality arrow very much in doubt,
however. Durazzo et al. 2008; Heath et al., 1997), cognitive ability
(also inverse, Alterman et al., 1990), increased psychological stress
(directly correlated, Brown et al., 1990), and co-morbid major
thought disorders (schizophrenia has a near perfect correlation with
treatment failure and subsequent relapse, see Cuffel & Chase,
1994; Iacono, 1998) have held up well under empirical study, but
other seemingly “obvious” psychological correlates of treatment
outcome have demonstrated little predictive validity.
As pointed out by Bauer in 2001 and again in 2012, most of
these potential psychological correlates suffer from some
combination of poor test-retest and inter-rater reliability,
self-report study designs, potentially confounding state
variables (like medication, intoxication, or withdrawal) during
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the pre-screening process, and differing definitions of “relapse”
itself during the main study phase.
Biological and Psychophysiological Relapse Predictors
Bauer (2012) criticizes the demographic and traditional
psychological metrics as being inadequate in the ways described
above, but he also lists a set of criteria that make for useful,
relapse-predictive metrics that seems worth repeating here.
According to his paper, for a pre-screen to be clinically useful,
it must be not only predictive of relapse, but also be:
A) Sensitive – avoiding false negatives;
B) Selective – simultaneously avoiding false positives;
C) Reliable – scored objectively and with minimal inter-
rater discrepancy;
D) Stable – remaining constant barring intervention (also
called test-retest reliable);
E) Cost Effective and Practical (i.e. Portable) – these all
relate to scalability issues;
He also states that there must be some “value added,” defining
this to mean that either the screening examines a variable that’s
predictive on its own, or else that “…the predictive validity…
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should exceed that of other variables which are more easily and
inexpensively measured.” (Bauer, 2012)
These rules seem to define well what the goal is, and
clearly the psychosocial traits above are too inconsistent across
studies to come close to hitting this high bar. Therefore,
biological and psychophysiological traits will now be examined
and tested against this list for utility as relapse predicting
metrics.
Psychophysiological Metrics
Quantitative electroencephalography (qEEG)
Quantitative Electroencephalography (qEEG) builds on the
technique of EEG, which dates to the 1920s. Both involve placing
electrodes on the scalp and measuring voltage changes in the
cerebral neocortex (the outermost brain layers) trans-cranially,
then processing and interpreting the
electric signal generated by the
brain and transduced by the
electrodes. The quantitative portion
of the term indicates that data are
being pooled by computer from many different
Figure 1. Old-style, 4-lead EEG vs modern high-resolution qEEG
head gear
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leads, and even many different subjects. These can then be used
to make more accurate, higher-powered statistical claims and even
to make inferences about groups.
This technology has actually been around for several
decades, though computers powerful enough to process enough data
to obtain adequate spatial resolution were prohibitively
expensive for a time. It is now not uncommon for a research-
grade, high-resolution qEEG setup to involve 96, 128, or even 256
leads connected to the scalp (see Figure 1), each lead recording
a different voltage several times every second, all integrated
into a meaningful pattern by the computer to which they are
connected (Ray & Cole, 1985).
Older rigs, like the one in Figure 1 on the left, required
taping the eyes and also the use of conductive gel – messy, time-
consuming, and long necessary to make an adequate electrical
contact with the scalp. This is no longer needed due to an
improved dry-electrode design which became available in 2006,
dramatically cutting experiment times. This new generation of
high-resolution, gel-less transducers enables a researcher to get
a much more accurate picture (spatial resolution has improved but
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remains marginal) of what brain regions are active at a given
time (temporal resolution is excellent) and to detect the neural
correlates of stimulus perception events, all with no
confinement, no messy gel, and in under an hour.
These “neural correlates of stimulus” are called Evoked
Potentials (EPs) if they are a direct result of the stimulus (a
loud noise, say, or a light flash) or else Event Related
Potentials (ERPs) if they are indirectly caused by the event, and
represent the cognition that occurs after the event itself. In
either case, these are named for their polarity (N for negative,
increased polarity peaks, and P for positive, depolarizing
valleys) followed by a number which indicates the characteristic
time in milliseconds after the triggering event when the
particular ERP appears. Some of the most
well described EPs are the N100/P200
complex – a negative (hyperpolarized)
peak followed by a positive
(depolarized) valley, at approximately
100 and 200 ms after the stimulus
respectively (See Figure 3) which follows any unexpected event,
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whether or not the subject is even attending to the area where it
appears (Fabiani, Gratton, & Coles, 2000). And by far the most
widely studied ERP is the E300, a long depolarizing wave-form
present only if the triggering event is both attended-to and
novel.
Alterations in the P300 ERP have been repeatedly
demonstrated to be strongly and specifically correlated with
relapsing subtype alcohol use disorders (Enoch et al., 2006;
Saletu-Zyhlarz, 2004; Bauer, 1997; Iacono, 1998; and Carlson,
Iacono, & McGue, 2002). Specifically, in relapsing type
alcoholics, the onset of the P300 waveform is delayed and the
amplitude is dramatically decreased, even after long–term
abstinence. Furthermore, it has been demonstrated that this
alteration is in fact a heritable endophenotype for alcohol use
disorders, that is to say it is present in many of the sons of
alcoholic fathers, long before they could possibly have had their
first drink. If they too show this characteristic alteration,
their already elevated risk for AUD roughly quintuples, to > 95%
(Bauer, 1997; Iacono, 1998; and Carlson, Iacono & McGue, 2002).
. Graph of time (ms) vs. EEG (and cell membrane) voltage for ERP
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This is tragic, of course, but it’s also crucial for
researchers. Since it amounts to the closest thing in existence
to a pre-alcohol-use test for alcoholism, pre-exposure altered
P300 gives researchers a means of pointing the causal arrow, a
way to determine causality instead of just correlation in
substance use studies, previously considered impossible.
For example, one may know that there are 6 or 8
physiological, neurochemical, and epigenetic differences between
an alcoholic and a non-alcoholic adult, but without the a priori
knowledge provided by the endophenotype (the highly predictive
test-trait), it becomes all but impossible to determine the
direction of the causation. Were the neuro-physiological-
epigenetic differences found in research what caused the drinking
problem? Or did the heavy alcohol exposure cause the differences?
Or was some as yet undiscovered force at work that caused both
drinking and differences? By knowing, in advance, which pre-teens
are likely to become alcoholics, it becomes possible for the
first time to begin to unravel that mess.
Bauer et al. (1993), along with Winterer et al. (1998,
2001), and Bauer (2001) have also identified a second qEEG
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predictor of elevated relapse risk. In this case a characteristic
elevated pattern of fast-β wave activity during resting states
which shows positive and negative predictivity values for time to
relapse of .75 and .74, respectively (Bauer, 2001). It should be
noted that these selectivity and sensitivity numbers are more
than triple the next closest correlate amongst the putative
traditional psychological metrics (this was seen in cognitive
ability, which showed + predictivity/selectivity at .21 in the
Alterman study from 1990). Replication and scaling of this work
is taking place, and even higher predictive validity has been
shown in subsequent experiments using the same protocol
(Ragnasamy et al., 2002, 2004; Porjesz et al., 2002, 2005).
Ironically, EEG results have historically been seen as
unreliable themselves, showing little test-retest or inter-rater
reliability, and having very poor spatial resolution (by Lehmann,
1984; Jervis, 1983; and Seyal, Emerson, & Pedley, 1983, amongst
others) and certainly this was true of the old analogue 4-channel
units with their paper rolls and waggling needles. But the tool
has come a long way since then, and these new results cannot be
ignored.
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The test-retest reliability question was addressed and
answered by Bauer in 1993 and again in 1997, where he
demonstrated that provided it’s held in the same orientation,
with the same equipment and following the same protocol, there is
no detectable difference in fast-β score or P300 variance across
trials and across examiners. The question should have been
settled once and for all by Iacono et al. in 1996, when they
demonstrated such high concordance of scores among separated
adoptees in a blinded study conducted at multiple sites that the
researchers initially thought they had a participant double
dipping for the stipend at both centers.
They were even more amazed when MZ twins, tested at
different locations on the same day, actually had slightly higher
concordance with each other than with their own scores a week later
(all 4 sets were near identical, but this screen has been called
the psychophysiological fingerprint because individual subjects’
signature waveforms are so unique and personal).
The Iacono (1996) study does however bring up one more
powerfully positive point associated with more widespread
adoption of qEEG as the tool of choice; the fact that like
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altered p300 waveforms, heightened fast-β wave activity during
resting states is not just a phenomenally good predictor of
relapse in abstinent alcoholics, it is also a genetically
determined heritable trait, and can function just as well in the
capacity of endophenotype for prospective SUD risk studies of all
kinds.
It is true that spatial resolution in qEEG will never be
that of fMRI, because of the way the process works- signals have
to penetrate the skull, the intervening (electrically active)
brain matter, etc. to reach a limited number of voltage dipoles,
and they get spread out and malformed in this process. These
messy data are then analyzed and reconstructed inside the
computer and then turned into a map by complex algorithmic
analysis. This has gotten much, much less necessary with the
introduction of the high-resolution 128 and 256 electrode caps,
to the point where it is now used to actually create imagery as
well as numerical data even, a process called LORETA EEG, and
these advances are coming at the same moment when the powerful
computing equipment necessary for the signal processing component
is falling precipitously in price. The spatial resolution has
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improved by a factor of 100 in the last decade alone, qEEG is
about 1/10,000th the price of fMRI, and the temporal resolution
is 100x that of even that powerful imaging technique (Mahmood,
2013).
Functional Magnetic Resonance Imaging (fMRI).
Functional magnetic resonance imaging (fMRI) is a technique
that takes advantage of the slightly ferrous character of
hemoglobin to measure blood flow. First the researcher obtains a
detailed structural image of the brain using traditional MRI
techniques, then adjusts the sensitivity of the magnet and
sensors to detect the miniscule magnetic difference in oxygenated
vs. de-oxygenated blood (called BOLD or Blood Oxygen Level
Dependant) in each three dimensional “voxel” (an abbreviation for
“volume-pixel,” a voxel is a tiny rectangular solid region within
the brain, on the order of ~1 mm3) as it varies over time. By
measuring each voxel and re-combining them in a computer, the
researcher is able to get a pixelated 3-dimensional picture of
the blood flow in the brain once he maps it back on to the 3-D
structural model obtained earlier with traditional structural
MRI. Actually, since fMRI is analogous to taking a 3-D video of
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blood flow, and each voxel is constantly changing with time, it’s
appropriate to say that a 4-dimensional model of the blood is
what’s ultimately created (Stevens, 2005).
Since active brain regions and structures use far more
oxygen than dormant or baseline regions, it’s possible to see the
different areas of the brain activate as the subject does
whatever task he is assigned while inside the magnet (looking at
pictures, playing “computer games” designed to measure some
psychologically significant variable or elicit a certain
cognitive or emotional response, etc…) Differences between these
patterns of activation in meaningfully different groups are what
one is hoping to find in an fMRI study- the group selection is
usually the independent, manipulated variable, and blood flow is
usually the dependent, observed variable (Stevens, 2005).
Because all brains are different sizes, there is a series of
complicated statistical parametric modeling steps that have to be
undertaken to “process” the 4-dimensional model in order for the
group comparisons to be meaningful. The brain has to be aligned
exactly so each voxel from each subject is in the same place. It
also has to be resized to fit the “standard” brain, so that for
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each subject, each voxel corresponds to the same brain region. It
also needs to be split into gray, white and CSF matter, and
digitally “smoothed” to even out the hard voxel edges. The
different groups of brain models are then averaged together and
differences in blood flow during a task can be analyzed across
groups. This process remains somewhat specialized and expensive,
but like all technologies prices are dropping rapidly (Stevens,
2005).
Some of these differences in blood flow correlate to the
variables under study. First off, in a 2007 study by Sinha & Li,
the procedure just described was performed on 40 subjects (newly
sober, detoxified alcoholics and cocaine abusers seeking
treatment at a local hospital) and 39 non-smoking, light-drinking
age, socio-economic, and ethnically matched controls (healthy
adults from the community, either paid or volunteering). While in
the scanner they were shown pictures designed to elicit cravings
alternating with neutral imagery, and asked each to self-report
their level of drug-desire or craving. After completion of
treatment he followed them for 90 days to assess treatment
outcome and monitor for relapse.
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Even with a follow-up period of just 3 months, significant
differences were noted between the relapsing and abstaining
groups. Increased activity in the medial pre-frontal cortex
(MPFC), a brain area associated strongly with reward salience,
during the drug cues, correlated to p < .02 inversely with time
to relapse, and also to p < .02 directly with amount used after
relapse. Additional effects of note between relapsers and
abstainers included increased cue-associated activity in the
posterior insula correlated with post-relapse drug use frequency,
and in the posterior cingulate (PCC) with amounts of drug used,
also post relapse.
Interestingly, though there were between-groups differences
between addicts and controls on almost every other metric, on the
self-reported “craving scale” they were indistinguishable from
each other, as were the abstainers; it showed no predictive
validity whatsoever. It would seem a true operational definition
for “craving” might be “increased medial pre-frontal cortex
activation during drug cue challenges” but self-reporting is once
again shown to be lacking. A similar study conducted by Grüsser
et al. in 2004 also showed drug cues and also asked for craving
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ratings on a 1-10 point scale. This time, however, a galvanic
skin response “sweat test” of the sort used in lie detection was
also included. Once again, no significant differences were noted
between controls, abstainers, and relapsers on either metric; on
the sweat test the group that would later relapse actually scored
slightly better.
But their brains told a different story.
The relapsing subgroup showed significantly elevated orbital
pre-frontal cortex (OFPC) activity during the drug cue imagery
compared to controls (p < .01) and relapsers (p < .04) both, even
as they were sweating slightly less and reporting an identical
level of subjective drug craving. The OPFC is a region
immediately adjacent to the MPFC involved in impulse control and
executive function and also long implicated in theories of
addictive etiology. Increased activity in this case could mean
more effort required to block the craving, apparently without the
subject even being aware it was happening.
Finally, a Pearson’s Correlation Coefficient was performed
to rule out any unrecognized confounding variables between the
relapsing and abstaining groups. Using this statistical method,
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lifetime drinking severity, time between last drink and scan
initiation, severity of alcoholism, comorbid depression, comorbid
anxiety, family history, and age were all ruled out as significant
contributors to the abstainer-relapser differences observed in
the study.
Conclusions and Extension
There are at least three different pre-treatment screening
protocols shown by this review to pass all five tests for being
clinically useful. It is time to retire the old, ineffective,
non-predictive metrics and embrace a new paradigm. This will lead
to far more efficient resource allocation, keeping those who
don’t need expensive inpatient treatment from having to be away
from home, while guaranteeing the space, money, and personal
professional attention that might finally reach the “forsaken
third” and give them back their lives.
P300 and fast-β qEEG based predictions of relapsing subtype
are more than three times as accurate at predicting relapse than
any of the psychological methods now in use, both in terms of
specificity and selectivity. They are also cheap; at this point a
qEEG can be administered by a non-expert after a few hours
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training, whereas most of the traditional methods require hours
of time from a holder of an advanced degree. The machines
themselves have gotten so inexpensive they’re sold as “toys you
can play with your mind.”
fMRI is, if anything, even more predictive than qEEG. It
does, however, have a ways to go in terms of price and
availability before it’s quite ready to be rolled out on a large
scale. But the cost of doing such pre-screening has dropped by a
factor of 25 in the last 10 years (Bauer, 2012) and they’re
getting cheaper and more predictive still every day; I certainly
wouldn’t bet against fMRI pre-treatment screening becoming the
standard within a decade.
qEEG and fMRI have been shown recently to predict relapse-
prone patients, with startling degrees of both specificity and
selectivity, and are, right now, readily available and approved
for use in human subjects. And they both add value, in several
different ways – both in terms of being the best available test
for the client, for society as a whole in terms of efficiencies,
and also in terms of enabling development of a still better
screening tool.
PSYCHOPHYSIOLOGY AND NEUROIMAGING PREDICT RELAPSE 29
There are limitations in all 3 methods of prediction
described above. Spatial resolution in the qEEG tests, costs and
eligibility in the fMRI, to name a few. Also, confounding state-
variables like intoxication or withdrawal during the pre-
screening process can interfere markedly with the predictive
validity of all the methods described. (Bauer, Covault, &
Gelernter, 2012). The gold standard therefore in the quest to
predict post-treatment relapse risk prior to treatment lies in
the one test where not even acute intoxication would be a
confound – the genetics of the individual patient.
Until recently it has been far too expensive, time-delayed,
and impractical to even consider determining the genotype of each
and every patient, but this is changing rapidly – according to
Bauer (2012) if present trends continue, in 10 years genotyping
will cost no more and take no longer than an x-ray. Even now
there are several different identifiable genetic polymorphisms
that seem to predict relapse to an almost unbelievable degree; in
one study, Edenburg, et al. (2004) found a 3 SNP haplotype in the
gene encoding GABAaR (a particular receptor for ᵧ-aminobutyric
acid (GABA), an inhibitory neurotransmitter that EtOH mimics the
PSYCHOPHYSIOLOGY AND NEUROIMAGING PREDICT RELAPSE 30
effects of) that correlates to relapsing-subtype alcohol
dependence at p < .000000022! In fact this gene of interest was
discovered and targeted as a direct result of the type of
psychophysiological metrics being advocated here- the qEEG was
being used as a pre-screen before genotyping areas identified in
the national COGA sample (Collaborative study Of the Genetics of
Alcoholism – a massive nationwide hunt for candidate genes.
Reich, 1996).
Thus the non-genetic methods could and should be deployed as
rapidly as possible; first because, as demonstrated in this
review, they possess enough predictive power to make an enormous
difference in relapse identification, because doing so would
likely generate a huge cost savings that could be put to work
helping the lost third of relapse-prone addicts, and also because
of the ancillary benefits that could be provided by leveraging
the data thus obtained in moving away from all subjective criteria
and toward a purely empirical, scientific approach.
The immediate and widespread use of qEEG, prior to admission
to treatment centers, as a prescreen for relapsers (who would
then receive even more help, support, and resources; non-
PSYCHOPHYSIOLOGY AND NEUROIMAGING PREDICT RELAPSE 31
relapsers would be directed to outpatient programs) would be
hugely beneficial toward reaching that goal more quickly. Data
from those screens could be combined with a simple cheek swab,
which would be de-identified, and used to refine and perfect the
genetic techniques that would be the ultimate goal. This is in
fact exactly what happened with GABRA2 in the Edenburg (2004)
study.
With each treatment program admission, not only would the
client receive the best and least invasive or confining course of
treatment for her individual disease, she’d be helping to advance
the science of addictive disease characterization and relapse
prediction as well. It is shown above that all three of these
techniques are capable of sorting the treatment-seeking
population into its hidden bi-modal distribution.
The type of genome-wide data collectable on a massive scale
under such a paradigm, has already been used to identify several
promising targets for the penultimate goal – discovering the true
neurobiological etiology of alcoholism, and then targeting that
mechanism directly and putting an end to it.
PSYCHOPHYSIOLOGY AND NEUROIMAGING PREDICT RELAPSE 32
Wojnar et al. got it started by looking at an individual
gene for relapse prevention in 2009 – the brain-derived
neurotrophic factor (BDNF) polymorphism they examined holds a
great deal of promise as a potential target for novel
pharmacotherapies, and it is already a superb test for relapse
likelihood. Bauer (2012) is looking at several genes as well, and
Zuo et al. (2013) in New Haven have a serine transporter gene
they’re beginning to look at which seems promising as can be.
The geneticists are waiting, they just need the data, and
the data collection will help the treatment seekers, while
simultaneously saving money throughout the system by shifting the
majority of addicts, who are not ultra-high-risk relapsers into
far less expensive outpatient programs, which have been shown to
be equally effective for that subgroup (Bottlender & Soyka,
2005). It’s past time to move beyond subjective “craving”
questionnaires and solve this problem.
PSYCHOPHYSIOLOGY AND NEUROIMAGING PREDICT RELAPSE 33
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