Neuronal Mechanisms of Intelligence.
Abstract
The aim of this research program was to identify the functional unit in the brain for reward or positive reinforcement. On the assumption that the simplest possible unit is the single brain cell, we have attempted to reinforce individual neuronal firing patterns by direct applications of neurotransmitters or drugs to the cell soma. Our most satisfactory experiments have been performed on large pyramidal cells in hippocampal brain slices. The probability of neuronal firing increased sharply when reinforced by contingent applications of dopamine or cocaine; the same injections applied independently of neuronal firing had no such effect and in fact tended to suppress activity. There is an indication of pharmacological specificity: included among substances that are ineffective are GABA, serotonin, acetylcholine, imipramine, ethanol, and saline. Some features of behavioral operant conditioning are not observed in the neuronal experiments; reinforcement schedules are ineffective and relearning is not enhanced. Such features thus may reflect properties of neuronal systems rather than of individual cells, Finally, we have begun to consider the biochemical events that may mediate the cellular reinforcement process. Proteins that control cellular firing rates may be modified (phosphorylated) via biochemical cascade involving the conjunction of Ca(++) influx and dopamine receptor stimulation. Originator supplied keywords include: Operant conditioning, Neuronal conditioning, Reward, Adaptive networks, Positive reinforcement, Learning.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1984
- Accession Number
- ADA151077
Entities
People
- J. D. Belluzzi
- L. Stein
Organizations
- University of California, Irvine