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Input – INTEGRATION - Output. Neil Greenberg Department of Ecology and Evolutionary Biology University of Tennessee. Input – INTEGRATION - Output. ENVIRONMENT. Receptors (sensory organs). General effectors (muscles and glands). CENTRAL NERVOUS SYSTEM. ENVIRONMENTAL INFORMATION ...
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Input – INTEGRATION - Output Neil GreenbergDepartment of Ecology and Evolutionary BiologyUniversity of Tennessee
ENVIRONMENT Receptors (sensory organs) General effectors (muscles and glands) CENTRAL NERVOUS SYSTEM
ENVIRONMENTAL INFORMATION ... (if its energy is detected) will be transformed and transmitted to progressively deeper (“higher”) levels of the nervous system , as needed. The detectors of environmental information have, throughout development, formed much of that nervous system and in turn are formed by the nervous system
We see the world not as it is, But as we are . . . Jacob’s Ladder connects earth and heaven, the real and the ideal
Input to Output From the retina to the muscles of the hand during a categorization task
Input – INTEGRATION - Output • Each element of the process of INPUT(SENSORY DETECTION – PERCEPTION), INTEGRATION(COGNITION / AFFECT / MOTIVATION – ASSIMILATION / ACCOMODATION), and OUTPUT can be viewed from the perspectives of • DEVELOPMENT • ECOLOGY • EVOLUTION • PHYSIOLOGY
We are MOTIVATED to meet our needs. The most fundamental need is to live, but beyond that many other needs must be met on the way to self-actualization -- and we live more-or-less well, more-or-less fulfilled. • a key neural structure in vertebrates is the midbrain, but the HYPOTHALAMUS coordinates AUTONOMIC activities of the nervous system – a principal mode of recognizing and coping with NEEDS not met.
Some of our needs are real, some perceived. The relative urgency of a particular need can more-or-less evoke the stress response, the behavioral component of which is AFFECT --our emotional systems-- which energize our motives to meet NEEDS Affect involves detection and evaluation of "salience" of stimuli and situation; approach and avoidance responses (often perceived as "emotional responses" and possessing autonomic elements; may be more-or-less "stressful"). • Several interconnected neural structures are often called the LIMBIC SYSTEM, including (especially) the n. accumbens and the amygdala
AFFECT amygdalaeare involved in detecting and learning what parts of our surroundings are important and have emotional significance (“salience”). They are critical for the production of emotion, particularly so for negative emotions, especially fear. prefrontal cortex (PFC) appears to play a critical role in the regulation of emotion and behavior by anticipating the consequences of our actions. (The prefrontal cortex may play an important role in delayed gratification by maintaining emotions over time and organizing behavior toward specific goals.)
AFFECT anterior cingulate cortex (ACC) is located in the middle of the brain, just behind the prefrontal cortex. The ACC is thought to play a central role in attention, and may be particularly important with regard to conscious, subjective emotional awareness. This region of the brain may also play an important role in the initiation of motivated behavior. ventral striatum is a group of subcortical structures thought to play an important role in emotion and behavior. The structure called nucleus accumbens is thought to be involved in the experience of goal-directed positive emotion (pleasure). (Addicts experience increased activity in this area when they encounter the object of their addiction)
AFFECT insular cortex is thought to play a critical role in the bodily experience of emotion, as it is connected to other brain structures that regulate the body’s autonomic functions (heart rate, breathing, digestion, etc.). (This region also processes taste information and is thought to play an important role in experiencing the emotion of disgust.)
COGNITION, consciously or non-consciously, modulates our many simultaneous perceptions, assesses their relevance to meeting needs, integrates them with each other and those in memory, and deploys the mechanisms to meet those needs. It is a major advantage to be able to adjust behavior to changing circumstances when the reflexive and automatized functions are insufficient. It involves selection and assessment of alternative inputs and outputs of which the organism may or may not have some level of conscious awareness. It may also involve memory and internal representations (models) of current circumstances and possible outcomes of specific responses. In humans, this involves the exercise of reflection and foresight • Key neural structures are parts of FOREBRAIN, especially prefrontal cortex in "higher" vertebrates
REFLEXES and their CONTROL • Reflexes protect us • Organized at a “lower level of cotrol for rapid response • Can be over-ridden
IMPULSES and their CONTROL • Reflexes protect us • Organized at a “lower level of cotrol for rapid response • Can be over-ridden
VALIDATING INFORMATION, BELIEFS IS IT REAL? Are my relationship(s) with phenomena reliable? Can I count on the consistency of perceived cause and effect? CORRESPONDENCE:does our inner model of the outer world correspond to reality?
VALIDATING INFORMATION, BELIEFS IS IT REAL? Do my new experiences resemble previous ones? ...fit in to my mental model? Need they be assimilated or accommodated or ignored? COHERENCEDo new percepts fit in with our other experiences, do they tell a satisfying story?
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
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)
DISORDERS of BELIEF? Acceptance of experience that doesn’t correspond to external reality:kinds of hallucinations, Bonnet’s Syndrome(filling in scotoma),body dismorphic disorder (?) (False positive (confident match with memories); Type I Error)) MORE CONSERVATIVE 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))
CORRESPONDENCE (reality testing) and COHERENCE (cognitive contextualizing) work in lockstep and in balance to provide a sense of CONFIDENCE. The highest confidence is the “truth.”
Kant: "The senses cannot think, the understanding cannot see.”