Dendrite decline in schizophrenia

Preliminary evidence indicates that a specific class of frontal-brain-cell connections shows dramatic reductions in schizophrenia. This disengagement of certain neurons from several other brain regions may contribute to thinking and memory problems typical of schizophrenia, contend Leisa A. Glantz and David A. Lewis, neuroscientists at the University of Pittsburgh.

Glantz and Lewis obtained samples of brain tissue taken at the autopsies of 15 adults who had experienced schizophrenia, 15 adults who had dealt with major depression or other psychiatric conditions, and 15 adults who hadn’t received any psychiatric diagnosis. Next of kin granted consent to the researchers for each brain donation.

Cell staining combined with computer-enhanced reconstructions of neurons showed that the schizophrenia group had a much lower density of projections from neurons in a specific tissue layer of the frontal cortex, the scientists report in the January Archives Of General Psychiatry. The sprouting branches, or dendrites, receive messages from other neurons.

Reduced dendrite branching in this particular frontal location—which maintains contact with several brain structures that help to organize thought—occurred regardless of whether individuals with schizophrenia had received antipsychotic medication, the researchers say.

Bruce Bower has written about the behavioral sciences for Science News since 1984. He writes about psychology, anthropology, archaeology and mental health issues.