From: Lee Corbin (lcorbin@tsoft.com)
Date: Sat Oct 05 2002 - 15:13:01 MDT
IN http://www.extropy.org/exi-lists/extropians/1925.html
gts writes a convincing summary of his findings and suggestions
about the role of motivation within human beings. But it may be
best to first review his basic contentions that some of us
found problematic. The following can be found in his message
in the "Psych/Philo Brains want to cooperate" thread sent Mon
9/2/2002 11:05 PM:
> ...the axiom I proffered was this:
> "Every human behavior has a motivation."
> Apparently you thought I meant this:
> "Every human behavior has a motivation, and every human is conscious of
> his motivation for each behavior and is capable of speaking about it."
> No. I never claimed that all motives *had* to be conscious.
First, I must suggest that you try out your axiom
"Every human behavior has a motivation."
on friends or other people whose judgment you respect, and empirically
determine the extent to which it's found acceptable. I'll wager that
a lot of people besides Rafal and me find it problematic, and you should
be interested (if I'm right) in why.
Next, in the above nicely written statement from the archives,
you say
> We can learn a great deal about human motivation from the field of
> addiction science. This is a field with which I am well acquainted for
> professional reasons. This message is supported by several research
> abstracts, contained below.
Thank you for the effort.
> In an earlier message here I quoted from an article by Desmond Morris.
> In that article Morris states that every animal species can be
> categorized into one of two groups: the "specialists" and the
> "opportunists." The human animal is an opportunist, meaning that
> nature/evolution has provided us with no specialized survival skills.
> We've survived largely by staying busy as hunters and novelty seekers
> (this is in contrast to, for example, venomous snakes which have a very
> specialized skill: the snake can lie quietly in wait for its prey and
> thereby survive with relatively little physical activity relative to
> humans and other opportunistic animals, e.g., wolves).
We must keep in mind a possible reason for your inclusion in your
statement of this apparent digression: I presume that you utilize
theoretical findings about reward from "opportunistic behavior"
in your general conclusions.
> In neurological terms, the motivation to experience novelty is closely
> related to the motivations to eat, to use addictive drugs, to find
> comfort and shelter, to take risks, to seek sexual experiences, and yes
> even to engage in the socially constructive acts that we call
> "altruistic". Essentially all human motivations are, at least in my
> view, manifestations of the basic biological incentive to experience
> reward and satisfaction.
And of course, everything revolves around what is meant
by "all human motivations".
> The biological underpinnings of the human motivation to seek novelty
> seems to be located (like other forms of reward, including drug reward)
> in the mesolimbic dopaminergic system. Studies show increased activity
> especially in the nucleus accumbens when the organism is confronted by
> novelty...
Now I would most pressingly like to know if such increased
activity is seen when an organism merely avoids unpleasant
stimuli. For example, a pigeon is conditioned to walk back
and forth between two compartments to obtain enough to eat,
and this behavior settles into a long term routine. We
monitor the activity in the nucleus accumbens and the levels
of drugs in its brain. Presumably when first discovering that
he can obtain more food by checking out both rooms at the
end of the corridor, the novelty of the discovery raises
levels. So I am speaking of months later when a "normal"
level of all this has been reached.
We now cause the right 25% of the corridor to be electrically
charged so that when the pigeon wanders towards the right side
on his path, he receives a painful shock. The pigeon leans to
keep towards the left. Does this motivation to avoid the pain
result in increased activity in the nucleus accumbens, or in
increased drug levels? If it does, then your theory is
bolstered (though not, perhaps, disproved if that's not the
case).
> As Rafal likes to say, the cortex is also implicated in the reward
> experience, specifically the pre-frontal cortex. I certainly agree that
> the cortex is involved in the conscious recognition of pleasure and
> reward, and that in some sense this recognition cannot be removed from
> the experience of reward itself.
These issues and how we should speak about them appear
to be carefully treated in Joseph LeDoux's book "The
Emotional Brain", which my book group is reading right now.
> The mechanisms underlying the reward from novelty is described in the
> second abstract.
See the link at top to see the abstracts from gts's original
post (or below).
Lee
> ABSTRACT 1
> Habit-forming actions of nomifensine in nucleus accumbens.
> Psychopharmacology (Berl) 1995 Nov;122(2):194-7 (ISSN: 0033-3158)
> Carlezon WA; Devine DP; Wise RA
> Department of Psychology, Concordia University, Montreal, Quebec,
> Canada.
> Rats learned to lever-press when reinforced with response-contingent
> microinfusions of the dopamine uptake inhibitor nomifensine (1.7 nmol
> per injection) into the ventro-medial (shell) region of nucleus
> accumbens septi (NAS). The drug was not effective when similar
> injections were given either in random relation to lever-pressing, into
> the more dorso-lateral (core) region of NAS, or into the frontal cortex.
> Cocaine was also effective in NAS, but considerably less so. These data
> suggest that response-contingent dopamine uptake blockade within the NAS
> is sufficient to establish and maintain instrumental response habits.
>
> ABSRACT 2
> Novelty-evoked elevations of nucleus accumbens dopamine: dependence on
> impulse flow from the ventral subiculum and glutamatergic
> neurotransmission in the ventral tegmental area.
> Eur J Neurosci 2001 Feb;13(4):819-28 (ISSN: 0953-816X)
> Legault M; Wise RA
> Center for Studies in Behavioural Neurobiology, Department of
> Psychology, Concordia University, Montreal, Quebec, Canada, H3G 1M8.
> Mark.Legault@CRFS.Umontreal.ca.
> In vivo microdialysis in freely moving rats was used to monitor
> novelty-evoked elevations in extracellular dopamine in the nucleus
> accumbens septi (NAS) and to examine the role of the ventral subiculum
> of the hippocampus and glutamatergic transmission in the ventral
> tegmental area (VTA) on these elevations. Exposure to novel stimuli
> evoked investigatory activity and increased nucleus accumbens dopamine.
> Unilateral injections of the sodium channel blocker tetrodotoxin (0.16
> ng/0.5 microL) into the ventral subiculum ipsilateral to the dialysed
> NAS abolished novelty-evoked elevations in dopamine. Injections of
> tetrodotoxin into the contralateral VS did not prevent novelty-evoked
> elevations in nucleus accumbens dopamine. Unilateral perfusion (via
> microdialysis) of the ionotropic glutamate receptor antagonists
> kynurenic acid (1 mM) into the ipsilateral but not the contralateral VTA
> blocked novelty-evoked elevations in nucleus accumbens dopamine. Neither
> unilateral injections of tetrodotoxin nor unilateral perfusion of
> kynurenic acid disrupted investigatory behaviour. These data indicate
> that phasic elevations in nucleus accumbens dopamine evoked by exposure
> to unconditioned novel stimuli are dependent on impulse flow from the
> hippocampus and glutamatergic transmission in the VTA.
>
> ABSTRACT 3
> D2 and D4 dopamine receptor polymorphisms and personality.
> Am J Med Genet 1998 May 8;81(3):257-67 (ISSN: 0148-7299)
> Noble EP; Ozkaragoz TZ; Ritchie TL; Zhang X; Belin TR; Sparkes RS
> Department of Psychiatry and Biobehavioral Sciences, University of
> California, Los Angeles 90024-1759, USA. epnoble@ucla.edu.
> The relationship of various dimensions of temperament, measured by the
> Tridimensional Personality Questionnaire (TPQ), to polymorphisms of the
> D2 dopamine receptor (DRD2) and D4 dopamine receptor (DRD4) genes was
> determined in 119 healthy Caucasian boys who had not yet begun to
> consume alcohol and other drugs of abuse. Total Novelty Seeking score of
> the TPQ was significantly higher in boys having, in common, all three
> minor (A1, B1, and Intron 6 1) alleles of the DRD2 compared to boys
> without any of these alleles. Boys with the DRD4 7 repeat (7R) allele
> also had a significantly higher Novelty Seeking score than those without
> this allele. However, the greatest difference in Novelty Seeking score
> was found when boys having all three minor DRD2 alleles and the DRD4 7R
> allele were contrasted to those without any of these alleles. Neither
> the DRD2 nor the DRD4 polymorphisms differentiated total Harm Avoidance
> score. Whereas subjects having all three minor DRD2 alleles had a
> significantly higher Reward Dependence 2 (Persistence) score than
> subjects without any of these alleles, no significant difference in this
> personality score was found between subjects with and without the DRD4
> 7R allele. In conclusion, DRD2 and DRD4 polymorphisms individually
> associate with Novelty Seeking behavior. However, the combined DRD2 and
> DRD4 polymorphisms contribute more markedly to this behavior than when
> these two gene polymorphisms are individually considered.
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