Dependence of Cortical Plasticity on Correlated Activity of Single Neurons and on Behavioral Context

• Published in: Science (American Association for the Advancement of Science) Vol. 257; no. 5075; pp. 1412 - 1415
• Main Authors: Ahissar, Ehud, Vaadia, Eilon, Ahissar, Merav, Bergman, Hagai, Arieli, Amos, Abeles, Moshe
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for the Advancement of Science 04-09-1992; American Association for the Advancement of Science
• Subjects: Acoustic Stimulation; Action Potentials; Animals; Auditory Cortex - physiology; Behavior, Animal - physiology; Behavioral neuroscience; Behavioral psychophysiology; Biological and medical sciences; Classical conditioning; Conditioning (Psychology); Connectivity; Electrophysiology; Fundamental and applied biological sciences. Psychology; Histograms; Learning; Macaca fascicularis; Mammals; Mental stimulation; Neurobiology; Neuronal Plasticity - physiology; Neurons; Neurons - physiology; Neuroplasticity; Physiological aspects; Plasticity; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Psychophysiology; Synapses - physiology; Cerebral cortex; Discharge pattern; Monkey; Central nervous system; Electrophysiology; Learning; Vertebrata; Mammalia; Animal; Cross correlation; Plasticity; Primates; Behavior; Response contingency; Brain (vertebrata)
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1529342

It has not been possible to analyze the cellular mechanisms underlying learning in behaving mammals because of the difficulties in recording intracellularly from awake animals. Therefore, in the present study of neuronal plasticity in behaving monkeys, the net effect of a single neuron on another neuron (the "functional connection") was evaluated by cross-correlating the times of firing of the two neurons. When two neurons were induced to fire together within a short time window, the functional connection between them was potentiated, and when simultaneous firing was prevented, the connection was depressed. These modifications were strongly dependent on the behavioral context of the stimuli that induced them. The results indicate that changes in the temporal contingency between neurons are often necessary, but not sufficient, for cortical plasticity in the adult monkey: behavioral relevance is required.