“TRUTH in the BRAIN: The NEUROETHOLOGY of BELIEF” Neil Greenberg University of Tennessee Knoxville, TN USA QI and COMPLEXITY.Consciousness Reframed 2004…....6th International Research Conference.
"Beauty is truth, truth beauty, -that is allYe know on earth, and all ye need to know.“ (Keats, Ode on a Grecian Urn)
TRUTH[like SCIENCE] is . . . “ . . . nothing but the expression of the necessary mode of working of the human mind” T.H. Huxley (1863)
CONFIDENCE Much of our behavior is structured by the possession and pursuit of confidence in the validity of our beliefs – their “truth.” The neuroethology of consciousness and its dysfunctions have identified two general processes that are critical to the sense of doubt or confidence in the veracity of a belief.
TESTING for TRUTH These processes are centered in the brain and involve subjecting units of incoming information (percepts) to two complementary “tests” (reality-testing and theorizing). These tests bear a striking resemblance to the two prominent philosophical views of “truth,” correspondenceand coherence.
Finding CORRESPONDENCE is an essential skill because the representation of the world within us must be valid "Knowledge is the conformity of the object and the intellect" (Averroes d.1198)
Finding COHERENCE is an essential skill because the world is known to us only in fragments Life is the art of drawing sufficient conclusions from insufficient premises. (Samuel Butler Notebooks (1912) ch. 1)
the interplay of COHERENCE and CORRESPONDENCE is regarded as the essential reciprocally related aspects of “intelligence” by psychologists (Sternberg) Our purpose today is to examine the evidence that these two functions are represented in the human brain and that they work together to create a sense of truth.
DEEP TRUTH A biological perspective on “truth” emphasizes its developmental, ecological, evolutionary, and physiological constraints – the four points of view of “DEEP ethology.” “Proximate” causes of our sense of confidence in the truthfulness of a percept involves the brain. A promising place to begin involves the effects of the stress response on the brain and the connections between key brain structures, including the basal ganglia and the frontal cortex.
DEEP Ethology • Description • Development • Ecology • Evolution • Physiology
DEEP Ethology • Development • As we mature and experiences accumulate, our confidence in the reality of a percept increases: • Dreams and other self-generated experiences are progressively distinguished from veridical experiences • Social referencing helps shape or corroborate the “meaning” of percepts by trusted caregivers
DEEP Ethology • Evolution • To be a successful species, our beliefs don’t have to be true – they only have to represent our needs well enough to serve our biological fitness – competence to survive and thrive. • FITNESS – involves the transmission of biologically relevant information across the generations. This information involves: (a) genes (“direct fitness”) and (b) memes (culture, “indirect fitness”)
DEEP Ethology • Evolution • There is a considerable fitness advantage in having confidence in the outcomes of actions • This confidence involves expert self-knowledge, particularly when exploring new needs and the boundaries of competence and understanding • Communication within an individual to provide self-knowledge precedes communication between individuals
GNOTHI se AUTON To be an effective, competitive organism, we would be wise to follow the advice of the Oracle at Delphi: “Gnothi se auton” (Know thyself) Is this the primal function of art? the ancient ruins of the sanctuary of Apollo at Delphi. is spread out over the southern slopes of Mount Parnassos, beneath the Phaidriad rocks.
DEEP Ethology • Physiology • The central nervous system is the proximate cause of behavior • Sensory input and the percepts they generate, interact with each other and past experience to orchestrate specific behavioral actions • The orchestration of cerebral structures underlying motivational, affective and cognitive functions is profoundly affected by the endocrine systems such as stress
TRUTH in the BRAIN As stimuli are detected and information transformed and integrated in the brain, we ascertain the relative confidence in the “truth” or “reality” of an experience. This is obviously a function of cerebral processing. For example, the localized excitement associated with an epileptic episode may evoke, “strong feelings of conviction and belief that what one is experiencing at the moment is of the utmost importance or is expressive of the absolute truth” (P.D. MacLean 1997 discussing “limbic epilepsy”)
TRUTH in the BRAIN For example, the anterior cingulate cortex (ACC) is important to the manner in which incoming information is attended and compared to resident information of which an individual is more-or-less conscious. Dissonances that may emerge from this comparison are potentially threatening and may thereby evoke elements of the physiological stress response, the hormones of which can differentially affect specific brain sites and thus evoke specific mechanisms to ameliorate the effects of the stressor.
AESTHETIC EXPERIENCE and STRESS “STRESS” can be fruitfully defined as “the organism’s coordinated response to a real or perceived challenge to its ability to meet a real or perceived need.” Depending on the perceived urgency of the challenge, responses can range from autonomic reflexes through bodily changes coordinated with intense cognition. NEEDS range from the maintenance of physiological stability (homeostasis) through self-actualization (the maximizing of individual potential, fitness)
AESTHETIC EXPERIENCE and STRESS Responses to novelty – including art defined as “the expressive exploration of the boundaries of experience” are inherently stressful, as experienced in the appreciation as well as the creation of art. The physiological stress response and its psychoactive influences increase as mismatches between experiences and beliefs are experienced . . . The increasing stress response includes energizing the cerebral actions that test experience and establish relative confidence in its validity . . .
an early expression of the stress-reducing effects of establishing confidence: “ . . . Argument [coherence] brings conclusions and compels us to concede them, but does not cause certainty nor remove the doubts in order thatthe mind may remain at rest in truth, unless this is provided by experience [reality-testing]” Roger Bacon (1268)
The Anterior Cingulate Cortex The ACC is a stress-sensitive site that has the potential to affect our confidence in beliefs. Spindle cells project to many sites but especially FPC where responses that compensate for “error-detection” are selected and initiated. While often regarded as part of the emotion-processing limbic system, ACC is more likely a specialized neocortical structure that can also deploy mechanisms of the autonomic nervous system by which we recognize activation of the stress response.
Anterior Cingulate Cortex (ACC) ACC appears to generate brain waves manifesting “error-related negativity” (ERN) associated with the detection and correction of errors. Alternatively, the ERN may indicate an affect-laden response to a mismatch between expectancies and outcomes.
The Anterior Cingulate Cortex ACC is thus a leading candidate for the site of integration of emotional and cognitive functions, of which reconciling internal truths to external realities may be particularly prominent. Such reconciliation involves compensating thoughts (which can redirect attention) or actions (which may remove or moderate the stressor). Stress-moderating actions include the externalization of beliefs in ways that explore their validity, embracing art in both its aesthetic as well as therapeutic sense.
LEFT BRAIN Coherence: creates a “stable and internally consistent belief system – works hard to “save appearances” (Ramachandran 1998) RIGHT BRAIN Correspondence: tests reality and if damaged, “confabulation runs rampant” (Ramachandran 1998)
LEFT HEMISPHERE Probabilistic reasoning (Osherson et al 1998) Abstract object recognition (Marsolek 1999) Bias toward “local attention” and visual processing (inf occipital cortex) (Fink et al 1996) RIGHT HEMISPHERE Deductive reasoning (Osherson et al 1998) Specific object recognition (Marsolek 1999) Bias toward “global attention” and visual processing (lingual gyrus) (Fink et al 1996)
DISORDERS of TRUTH • Hallucinations we know are not real (Bonnet’s syndrome) • Hallucinations we believe are real (Schizophrenia) • Erroneous beliefs about one’s competence (right parietal hemisphere damage) • Correct beliefs about one’s competence (left parietal hemisphere damage)
DISORDERS of TRUTH • Anosognosia (occasional result of a right (but not a left) hemisphere stroke) can lead otherwise normal patients to deny the existence of obvious problems (such as paralyzed limbs) • In the absence of right hemisphere reality-testing, the left hemisphere weaves the best story it can, often with memories and imagined “facts” – it “confabulates.”
SUMMARY Establishing CONFIDENCE in our understanding of the CAUSES and CONSEQUENCES of phenomena in the world and in our relationship to them are BIOLOGICAL ADAPTATIONS – they meet a critical biological need. “TRUTH” represents high CONFIDENCE in our beliefs, including a SENSE of SELF. We are endowed with complementary neurobehavioral mechanisms to establish CONFIDENCE by “testing” percepts and beliefs for their VALIDITY.
SUMMARY The principal tests are those of CORRESPONDENCE and COHERENCE, localized in the RIGHT and cerebral LEFT hemispheres, respectively. Disorders of TRUTH – both excesses and deficits –are apparent when key cerebral structures are impaired. ART – its creation and appreciation – are a principle means by which we test the boundaries of our competence for understanding and communication and explore the VALIDITY of the SELF
"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