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THE NEUROPSYCHOLOGY of BELIEF

THE NEUROPSYCHOLOGY of BELIEF. Neil Greenberg Departments of Ecology, Medicine, and Psychology University of Tennessee, Knoxville. October 2008. Tiffany, “Education” (1890). ULTIMATE OBJECTIVES. What does it all mean? Why do I care?. UT-GSM 2008. INTERMEDIATE OBJECTIVES.

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THE NEUROPSYCHOLOGY of BELIEF

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  1. THE NEUROPSYCHOLOGY of BELIEF Neil Greenberg Departments of Ecology, Medicine, and Psychology University of Tennessee, Knoxville October 2008 Tiffany, “Education” (1890)

  2. ULTIMATE OBJECTIVES • What does it all mean? • Why do I care? UT-GSM2008

  3. INTERMEDIATE OBJECTIVES • Can the neuroethological perspective help us understand forms of gnosis with precision enough to understand their causes and remediate their dysfunctions? • Can growing insight into the implicit and explicit forms of gnosis allow us to help the system struggling to maintain stability in the face of changing competencies? UT-GSM2008

  4. PROXIMATE OBJECTIVES Review research experiences that may help me think about cognitive dysfunction in new ways, including: Stereotyped behavior in a model animal Ventral striatal lesions and social agnosia Subclinical stress modulating social hierarchy Reciprocity of two forms of reality testing: correspondence and coherence UT-GSM2008

  5. INTEGRATIVE BIOLOGY of BEHAVIOR DESCRIPTION: THE ROCK. Precise behavioral description enables confident analysis of prospective causes and consequences of a behavioral pattern from the perspectives of: DEVELOPMENT (e.g., changing competence of perceptual, integrative, and action systems throughout the organism’s ontogeny and environmental experiences) ECOLOGY (e.g., specific behavioral patterns can be highly context dependent and are assessed for optimality in specific environments at specific times)

  6. INTEGRATIVE BIOLOGY of BEHAVIOR EVOLUTION (specific behavioral patterns have assembled from often isolated traits which have been “recruited” to work together under the influence of alternate unifying control system. PHYSIOLOGY (e.g., the diverse structures which converge to control specific behavioral patterns are modulated by diverse stress hormones (epi, norepi, ACTH, MSH, CS, opioids, prolactin, angiotensin), each most effective at a specific concentration at a specific site) This is “DEEP” ethology to undergraduates

  7. GNOSIS • Beliefs (or the lack thereof) engage specific neural structures that coordinate and represent correspondence(…of perceptual information with reality) and coherence (…of information with other preceding or collateral percepts) • DISORDERS of BELIEF • Can reflect an uncoupling of specific neural structures leading to investments of confidence without the appropriate checks and balances

  8. WHAT is BELIEF? Belief is the psychological state in which an individual is more-or-less confident in the validity of a proposition. (this need not be conscious it is tested at every level by feedback loops (confidence can translate into biological fitness) If confidence is sufficiently high, the belief is recognized as TRUE ! And we may rest satisfied

  9. BASAL GANGLIA • Stereotyped behavior is an efficient expression of behavioral patterns that have evolved to be precise (ritualization). • But under stress these can become dysfunctional stereotypieswhich can in principle be anxiolytic.

  10. BASAL GANGLIA • Animal Model • -- In the lizard, Anolis, precise lesions in ventral striatum will eliminate the species typical display that evokes social aggression without affecting any other known behavior, including courtship. • -- When aggression is allowed, social hierarchies quickly form and subordinates manifest an adaptive stress response that enables social stability. • --The stress hormone profile changes from uncontrolled to controlled coping, and • -- subordinates neglect reproductive opportunities (further reducing stress and stabilizing the male-male relationship.

  11. An aside on HOLONS • Behavioral responses to meeting needs at one end of our system of hierarchically layered control and feedback. Loops exists from “local reflexes” through forebrain and can even be extra-somatary . • Transferring control between hierarchical levels is a neglected but crucial dimension of the system

  12. SURVEY: stress-sensitive behavior • Detection, Arousal and Attention(steroids affect sensory thresholds, EPI intensifies; acute CS enhances salience) • Activity(CRF facilitates in familiar habitat, inhibits in unfamiliar habitat) • Exploration(CRF and ACTH enhances effects of novelty, CS facilitates) • Learning and memory( EPI, CRF, MSH facilitate acquisition) • Cognition( catecholamine modulation; taking prefrontal cortex “offline” (Arnsten))

  13. SURVEY: stress-sensitive behavior • Feeding( CS stimulates or inhibits depending on circulating levels) • Aggression(ACTH suppresses, CS increases or decreases depending on circulating levels) • Social Dominance(CS increases submissiveness) • Reproduction( ACTH, CS, opiods, and prolactin impair HPG axis) • Dysfunctional behavior(stereotypies, neuroses, psychoses)

  14. COPING RESPONSES:delicately balanced alternatives ! • “Fight or flight” (the classic stress alternatives to imminent aggressive threat –not only in animals with a cerebral cortex!) • “Flee or freeze”(lizards can apparently calculate prospects for survival based on external threat , internal resources, and environmental possibilities) • “Green or brown” (the Anolis carolinensis dermal chromatophore –the “chromomotor model”)

  15. The Anolis Model

  16. BASAL GANGLIA “a major evolutionary trend is the progressive involvement of the cortex in the processing of the thalamic sensory information relayed to the BG of tetrapods. … new insights [include] the segmental organisation of the midbrain dopaminergic cell groups, the occurrence of large numbers of dopaminergic cell bodies within the telencephalon itself, and the variability in connectivity and chemoarchitecture.” (Smeets et al. 2000)

  17. VENTRAL STRIATUM and STRESS Ventral striatum monitors reliability of predictions made in prefrontal cortex … Such expectations can be cognitive as well as motor … “All dissonances evoke stress in proportion to the error function… and perceived urgency of need that may be compromised” UT-GSM2008

  18. Connection between BASAL FOREBRAIN, and AMNESIA ?? A bleed into the anterior portion of the left basal ganglia. (nAcc & some of internal capsule, some vent caudate) Attention & executive function unimpaired, but anterograde amnesia. nucleus accumbens Goldenberg et al. 1999) UT-GSM2008

  19. STRESS “… acute, uncontrollable stress: We become distracted and disorganized, and our working memory abilities worsen, leaving prepotent or habitual responses to control our behavior …” • Catecholamines (dopamine, norepinephrine, and epinephrine) reallocate • somatic resources for fight or flight (heart & muscles enhanced, stomach inhibited) • and cerebral resources for thought or prepotent action (subcortical structures enhanced, cerebral cortical structures inhibited via DA D1s and NE A1s) – Arnsten 1998 Perceived lack of control: impaired pfc (“impulsivity”) perceived control: enhanced performance of simple well rehersed acts UT-GSM2008

  20. STRESS • . • Stimuli that affect the relative activation or relaxation of the stress response can be real or perceived. (placebo effect?) • Stressors are assessed for controllability • Perceived as controllable or uncontrollable, • Stress responses are hierarchically evoked, and can affect different neural structures at different levels of activation UT-GSM2008

  21. Effects of glucocorticoids in depression Drevets & Schulkin 2003

  22. HOW IS BELIEF ESTABLISHED?The source of “knowledge claims” • CORRESPONDENCE: Empiricism and Reality-Testing • data-based, induction-driven • PERCEPTS CORRESPOND to reality • COHERENCE: Rationalism and Story-Telling • theory-based, deduction-driven • PERCEPTS COHERE with each other

  23. An aside about how beliefs are derived • We each bring congenital (relatively fixed), acquired (experiential, relatively flexible), and circumstantial “personality” to new information. • For example, our disposition to assimilate / preserve tradition versus accommodate / innovate could be attributable to subclinical stress • Learning styles are also part of this “personality” (Kolb) • Concrete Experience - (CE) • Reflective Observation - (RO) • Abstract Conceptualization - (AC) • Active Experimentation - (AE)

  24. Are beliefs more important than truth?TRUTH and STRESS SELF-DECEPTION serves a vital function(Daniel Goleman’s use of Ibsen’s term: “Vital Lies” 1985) “You can’t handle the truth!” (Jack Nicholson in In “A Few Good Men,” 1992) DENIAL ---The more-or-less “…willing suspension of disbelief…” (Wordsworth) – is that the function of art?… to provide a safe zone for exploring the otherwise troubling, stress-evoking truth? Or of myth? (“theory” (theoria) used to be an “enchanted circle”)

  25. DISORDERS of BELIEF?Correspondence awry Acceptance of experience that doesn’t correspond to external reality:kinds of hallucinations; Bonnet’s Syndrome(filling in scotoma); dismorphic body; pareidolia. (False positive (confident match with memories); Type I Error; gullible, trusting) Denial of experience that corresponds to external reality: agnosias: eg, visual(left occip), associative, anasognosia(denial of dysfunction / right cerebral cortices), prosopagnosia(faces) (False negative (failure to match with memories); Type II Error; skeptical, wary)

  26. DISORDERS of BELIEF?Coherence awry PLACEBO EFFECT: reification of EXPECTATIONS • Acupuncture IS effective in many cases, but application at arbitrary site is comparable (Melchart et al. 2005) • Antidepressant medications can be 80% replicated with placebo (Kirsch et al. 2002) • Parkinson’s patients experience an endogenous dopamine “rush” when nigrostriatal system activated by placebo (expectation of reward – Fuente-Fernandez 2001)

  27. PLACEBO EFFECTnot merely subjective? Extra endorphins were also released from sites not usually engaged in analgesia, including • rostral anterior cingulate (perception of degree of pain)(ACC: autonomic, error-detection, conflict resolution or management) • insular cortex (receives somatic pain information) • nucleus accumbens (assesses urgency of pain) • dorsolateral prefrontal cortex(involved in decision making, interpretation, and selective attention) BUT, only in those that expected relief. (Zubieta et al. 2005) . . .

  28. Anosognosia • ANOSOGNOSIA(from the Greek: A + nosos (disease) + gnosis (knowledge) • Ignorance or denial of the presence of disease • Most famously of paralysis in patients with non-dominant (usually right) parietal lobe damage -- patients deny their hemiparesis, & confabulate rationalizations • Detection of discrepencies impaired • When the right hemisphere is denied input from the reality-testing of the left hemisphere; internal model is “untested” by feedback, leaving left-side function seemingly “hallucinated.”

  29. Putative Causes of Anosognosia • Freudian denial: avoidance of confrontation with dysfunction, preserve self image. • Phantom function: as with phantom limbs, signals from motor cortex go to parietal monitoring area AND to muscles (that no longer exist). In the absence of feedback (confirming dysfunction) parietal area prevails • Right hemisphere impairmentby muting emotionality, and flattening affect, might create the appearance of indifference

  30. Confabulation: The illusion of coherence • “The production of coherent but fictitious stories” • First observed by Korsakoff in alcoholics (thiamine deficiency) • Can be provoked (eg., to avoid embarassment) or spontaneous (Schnider 2003) • Involve anterior limbic structures (orbitofrontal) • Impressive when right hemisphere (and its “reality-check” on the left hemisphere) is damaged

  31. Causes of Confabulation • Right hemisphere stroke: denial of left side paralysis. • Korsakoff’s syndrome: inability to form new memories due to temporal lobe dysfunction. • Acting out after a hypnotic suggestion will be rationalized with improvised confabulations • Schizophrenia: confabulations to rationalize hallucinations or to justify paranoia • Capgras syndrome: incomplete sense of who owns a familiar face: alien imposters?

  32. LEFT - RIGHT HEMISPHERE LATERALITY • When separated, EACH hemisphere is UNAWARE of the ipsilateral world • Yet neither is aware of being incomplete • Each functions as best it can with the information available

  33. LEFT HEMISPHERE Coherence: creates a consistent belief system – works to “save appearances” (Ramachandran 1998) Probabilistic reasoning (Osherson et al 1998) Abstract object recognition (Marsolek 1999) Activated by familiar percepts (Goldberg 2001) RIGHT HEMISPHERE Correspondence: “skeptical,” tests reality and if damaged, confabulation runs rampant (Ramachandran 1998) Deductive reasoning (Osherson et al 1998) Specific object recognition (Marsolek 1999) Activated by unfamiliar percepts (Goldberg 2001)

  34. The senses cannot think, the understanding cannot see. Immanuel Kant, Critique of Pure Reason, 1781

  35. "Our life is an apprenticeship to the truth that around every circle another can be drawn; that there is no end in nature, but every end is a beginning, and under every deep a lower deep opens" --Ralph Waldo Emerson

  36. BELIEFS are the GROUND of ACTION we are our experiences and expectations in action Experience (and therefore expectation) affect our perceptions. Apparently singular beliefs upon which we may base an action in the world is mixture of multiple beliefs, the validity of which we may be more-or-less confident. Even if our memories, current perceptions and skills at prognostication were perfect, we live immersed in a real world of which we have at best a fragmentary idea because as an organism, the information being processed moves in intermittent bursts with gaps devoid of information in between. Further, as attention is recruited, the receptive fields of some information is suppressed so that other information can receive more intense representation.

  37. BELIEFS are the GROUND of ACTION fragmentary percepts appear seamless Our sense of continuity and completeness involves interpolation and extrapolation -- modes of "filling in“ or “extending” which are very good, but cannot be perfect, although imagining and aiming at perfection (“ideals”) guides development. In fact, they are good enough for genuine success in everyday living -- for enhancing our biological fitness -- but when pushed to the boundaries (as humans are powerfully disposed to do) the gaps may become apparent, fault-lines appear, and the stress response is more-or-less evoked: “Stress is a coordinated physiological response to a real or perceived threat to our ability to meet our real or perceived needs.”

  38. BELIEFS are the GROUND of ACTION reciprocal interactions provide confidence We cope with stress by increasing selective inattention at the same time as other sensory channels and their central processing are energized. It is important to note that these fragments of information we accept from the world are obtained by one part of the brain, tested for validity in another, and forged into beliefs by yet another. These specific cerebral functions work together to provide confidence in the validity of a belief. Confidence is obtained by subjecting experience to two tests: correspondence("reality-testing") and coherence ("theorizing").

  39. BELIEFS are the GROUND of ACTION truth is a ripple on the ocean of reality REALITY-TESTING relies heavily on empiricism and the senses while THEORIZING relies heavily on deduction and reason. The more-or-less confidence we may have in our beliefs depends on the effort invested in assimilating or accommodatingthe belief into the pre-existing world view. We cope by selective inattention, some of which is obligatory and some facultative It is important to note that fragments of information we accept from the world are obtained by one part of the brain, tested for validity in another, and forged into beliefs by yet another. These specific cerebral functions work closely together to provide confidence in a belief. Very high confidence is regarded as TRUTH

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