> From: "Young, Mark" <MYOUNG92@psy.soton.ac.uk>
> Date: Fri, 24 Feb 1995 14:10:12 GMT
> The Ader & Cohen material on Pavlovian conditioning can apply to a
> lot of areas - the diabetics, the hungry and the alcoholic. However,
> it works the other way for the depressed. The biological account
> posits that low levels of serotonin is a cause for depression. But
> antidepressants, which raise serotonin levels very quickly, do no
> "work" for 10-14 days. Also, the drugs stop boosting
> neurotransmitter levels after a few days, when serotonin levels drop
> back to normal. Yet mood lifts a week or so later.
The understanding of the mechanisms of mood is minimal. Nothing like a
coherent cause/effect explanation is in sight yet, molecule-by-mood.
Yet we know that certain antidepressent drugs (lately the serotonergic
ones) work. The ill-understood 10-14 day lag is only the tip of the
iceberg when it comes to what is NOT understood about all this, and it
presents itself as such a prominent mystery probably only because the
REST of our simple cause/effect ideas about what's going on here are
wrong or incomplete too.
> The fact that, in the Ader & Cohen expt, the effects of saccharin
> decay after 4 or 5 trials without the UCS can be explained by normal
> extinction, as identified by Pavlov. Presumably, similar phenomena
> such as spontaneous recovery would also occur. The reason this would
> not work as an alternative to therapy is that the CR fades over time,
> such that it may not be effective at a time when CS treatment becomes
> an option.
> The use of counterconditioning and desensitisation may be effective,
> although I'm curious: does the exploitation of extinction itself
> extinguish (i.e. will there be a spontaneous recovery of the phobia)?
Here's some material that may help:
Hugdahl, Kenneth; Fredrikson, Mats; Ohman, Arne. Preparedness and
arousability as determinants of electrodermal conditioning.
Behaviour Research & Therapy, 1977, v15 (n4):345-353.
ABSTRACT: Arousability, as defined through spontaneous
electrodermal responses, has been empirically linked to anxiety,
phobic symptoms, and outcome of systematic desensitization.
Previous data indicate that preparedness, as defined through
potentially phobic vs fear-irrelevant or neutral conditioned
stimuli, is an important determinant of electrodermal
conditioning. The present experiment compared 4 groups of 16
undergraduates selected to be high or low in spontaneous responding
during differential conditioning to potentially phobic or neutral
stimuli. It was found that the effects of these 2 factors were
essentially additive, i.e., conditioning and resistance to
extinction were better for phobic stimuli and for high-arousal
groups. The high-aroused group with phobic stimuli showed diffuse
responding during acquisition, not differentiating between
reinforced and unreinforced cues. However, it was the only group
that failed to extinguish during 20 trials, which indicates that
high arousal gives superior resistance to extinction particularly
for phobic stimuli.
To retrieve the following article, use this URL:
PREPAREDNESS AND PHOBIAS: SPECIFIC EVOLVED ASSOCIATIONS OR A
GENERALIZED EXPECTANCY BIAS?
Department of Social Science,
The City University,
LONDON EC1V 0HB U.K.
ABSTRACT Most phobias are focussed on a small number of
fear-inducing stimuli (e.g. snakes, spiders). A review of the
evidence supporting biological and cognitive explanations of this
uneven distribution of phobias suggests that the readiness with
which such stimuli become associated with aversive outcomes arises
from biases in the processing of information about threatening
stimuli rather than from phylogenetically based associative
predispositions or "biological preparedness." This cognitive bias,
consisting of a heightened expectation of aversive outcomes
following fear-relevant stimuli, generates and maintains robust
learned associations between them. Some of the features of such
stimuli which determine this expectancy bias are estimates of how
dangerous they are, the semiotic similarity between them and their
aversive outcomes, and the degree of prior fear they elicit.
Ontogenetic and cultural factors influence these features of
fear-relevant stimuli and are hence important in determining
expectancy bias. The available evidence does not exclude the
possibility that both expectancy biases and specific evolved
predispositions co-exist, but the former can explain a number of
important findings that the latter cannot.
KEYWORDS: Preparedness, phobias, biological preparedness, selective
associations, information processing biases, classical
conditioning, covariation assessment, cross-cultural studies.
> This still does not explain the anomalous depression results
> explained above - any ideas?
What is not explained in the depression results is a lot more than the
time lag; indeed, the fact that the time lag appears anomalous may just
be because of our simplistic and incomplete understanding of the full
causal mechanism involved.
> Desperately trying to relate this to circles now. Perhaps by
> relating it to established research, we avoid falling into this
> circle, which is essentially just a version of cognitive lockup (that
> Sherlock Holmes thing again - fitting facts to theory rather than the
> other way round). This is not a new idea - anyone (apart from
> Psych/Law students) heard of the cognititive interview?
Hermeneutics comes into the work on Pavlovian Conditioning of the Immune
Response when one extrapolates the trivial laboratory results on mice to
imagined real effects in the clinic (passing over the sticky problem of
extinction and effect size).
Some food for thought: so called "theory-saving" (the far-fetched
re-interpretation of seemingly negative results so as to support your
preferred theory) is a hermeneutic effect, even though it can happen
with an empirical theory too! In fact, this is the soft underbelly of
empiricism: Your THEORY may be empirical and falsifiable, but to the
extent that there is room for interpretation in both the theory and the
data (and how/why they fit), you could still be spinning around in
hermeneutic circles (not unlike Ptolemaic Epicycles, for those of you
who know the famous example of the earth-centered theory whose
proponents tried to save it against the Copernican Revolution by
inventing more and more far-fetched "epicycles" to explain the finding
that planets moved in eliptical paths rather than the circular ones
Ptolemy had posited).
Cure: Big, reliable results, supported by the literature, both
experimental and theoretical. This is not to say that revolutionary
results cannot and will not occasionally appear unexpectedly out of
left field, but you cannot play it as if that were the usual effect,
rather than the rare outlier. Otherwise you risk, like Polonius, going
completely hermeneutic, interpreting the amplified noise between the
radio stations as if it were whispering your name. Rather keep
looking for the reliable signal of the station.
Remember the old joke about conditional probability: Mrs. Jones is
WRONG to think that the (alleged) fact that Einstein was a slow learner
is good news for her own little late-bloomer, Jonas: If sometimes X
happens DESPITE Y, it does not follow that if Y is the case, X is any
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