Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Plasticity in value systems and its role in adaptive behavior
Autore:
Sporns, O; Almassy, N; Edelman, GM;
Titolo Testata:
ADAPTIVE BEHAVIOR
fascicolo: 2, volume: 8, anno: 2001,
pagine: 129 - 148
SICI:
1059-7123(200121)8:2<129:PIVSAI>2.0.ZU;2-H
Fonte:
ISI
Lingua:
ENG
Soggetto:
LOCUS-COERULEUS NEURONS; LONG-TERM POTENTIATION; REAL-WORLD ARTIFACT; PREFRONTAL CORTEX; VISUAL-CORTEX; SYNAPTIC PLASTICITY; DOPAMINE NEURONS; VIGILANCE TASK; MODULATION; RESPONSES;
Keywords:
value; plasticity; conditioning; reinforcement; categorization; vision;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Social & Behavioral Sciences
Citazioni:
50
Recensione:
Indirizzi per estratti:
Citazione:
O. Sporns et al., "Plasticity in value systems and its role in adaptive behavior", ADAPT BEHAV, 8(2), 2001, pp. 129-148

Abstract

Adaptive behavior requires the sensing of salient behavioral consequences which can act to modulate changes in neural connections linking sensory andmotor structures. In previous work, we proposed that salient sensory events trigger neuronal value systems capable of modulating synaptic plasticity. Here, we investigate the capacity of value systems to modulate their own responses in the context of various conditioning tasks. To this end, we implement a modifiable value system incorporating anatomical and physiological properties within Darwin V, a neuronal model embedded in a mobile real world device. While exploring an environment containing stimulus objects, Darwin V's visual maps develop object-related neuronal responses. Phasic responses of a value system initially triggered only by object-"taste" (innate value) modulate changes in connections between visual and motor neurons, thus linking specific visual responses to appropriate motor outputs. Over time, Darwin V is able behaviorally to discriminate between "striped" objects with positive value (appetitive behavior) and objects with "blobs" with negative value (aversive behavior) based on vision alone. In parallel with modification of visuo-motor connections, value-dependent modification also occursin connections from visual sensory maps to the value system itself. As a result, visual activity patterns become able directly to trigger value signals (acquired value). If acquired value is disabled, transfer of the value signal to stimuli preceding innately salient events does not occur, and behavioral responses due to aversive conditioning are subject to rapid extinction. If an auditory signal reliably precedes the visual appearance of an aversive object, Darwin V could be conditioned first to reject the object based on vision (primary conditioning), and subsequently based on sound alone (secondary conditioning). We compare the functional characteristics of value-dependent learning to formal notions of reinforcement learning. We suggestthat plasticity in sensory afferents to value systems may provide a neurobiological basis for mediating the changing effects of saliency on adaptive behavioral responses.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 19/09/20 alle ore 17:50:04