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)

New research findings about how nerve cells transmit signals are forcing researchers to overhaul their simplistic ideas about the nervous system. Topics highlighted include the multiple role of peptides in the nervous system, receptor molecules, and molecules that form ion channels within membranes. (Author/JN)

Discusses the process of aging in the brain, including some of the structural and chemical changes that take place in the nerve cells as they age. (CS)

Discusses current learning theories, indicating that though many psychologists and ethologists now agree on using a mechanistic approach, some linguists doubt its adequacy. Implications of research on the mollusk "Aplasia" to understand the learning process are included. (JN)