Provides comments on research studies related to memory systems, considering those exploring the nature of memory traces. One researcher suggests that memory trace circuits are extremely localized (as opposed to being diffuse), such that a lesion in a rabbit's brain can completely destroy the trace for a particular learned response. (JN)

Presents a hypothesis about the biochemical processes involved in memory storage. The postulated mechanism is initiated by a signal that is unusual but not unlikely to occur and produces an irreversible change in a key component of synaptic chemistry. Other features of the mechanism and experiments supporting the hypothesis are considered. (JN)

Reviews the features of two classes of learning theories. Reports evidence supporting a statistical configuration" theory, suggesting that temporal patterns of neurophysiological waves in the average activity of extensive anatomical brain regions may constitute the basis of subjective experience. (AL)

Describes the subdivisions of the human peri-Sylvian language cortex which were determined by stimulation mapping during craniotomies of four adult patients. (SA)

Progress is now being made toward ascertaining the specific effects of rearing conditions on brain and behavior, the properties of the environment that contribute to these effects, and the developmental periods in which brain tissue is most sensitive to environmental modification. (Author/RH)

Reviews a study which sought to obtain a quantitative metabolic map of the neurons mediating a specific memory. Research results support notions of cooperative processes in which nonrandom behavior of high ensembles of neural elements mediates the integration and processing of information and the retrieval of memory. (ML)

Describes how a behavioral system in Aplysia (marine snail) can be used to examine mechanisms of several forms of learning at different levels of analysis: behavioral, cell-physiological, ultrastructural, and molecular. Focusing on short-term sensitization, suggests how molecular mechanisms can be extended to explain long-term memory and classical…

Focuses on the brain processes and brain systems involved in learning and memory from a neuropsychological perspective of analysis. Reports findings related to the locus of memory storage, types of memory and knowledge, and memory consolidation. Models of animal memory are also examined. An extensive reference list is included. (ML)

Assesses the sensory and cognitive functions in a right-handed male before and after partial and complete callosal commissurotomy. (Author/SK)

Describes recent research findings in the area of neurobiology and its relationship to learning and memory. The article provides definitions of associative and nonassociative learning, identifies essential memory trace circuits of the mammalian brain, and discusses some neural mechanisms of learning. (TW)