The main strength of the hypotheses, advanced in this article, that schizophrenia involves (a) increased spontaneous transients, which relate to positive symptoms, and (b) decreased adaptive transients, which relate to negative symptoms, is the extensive set of findings that they explain (see Figs. 4–5 in the article). Directly and more definitively testing these hypotheses would ideally involv...

We have used confocal microscopy to monitor synaptically evoked Ca2+ transients in the dendritic spines of hippocampal pyramidal cells. Individual spines respond to single afferent stimuli (<0.1 Hz) with Ca2+ transients or failures, reflecting the probability of transmitter release at the activated synapse. Both AMPA and NMDA glutamate receptor antagonists block the synaptically evoked Ca2+ tra...