Learn More
We have examined the evolution of the concept of a Hebbian synaptic modification and have suggested a contemporary definition. The biophysical mechanism demonstrated in vitro to control the induction of one type of hippocampal LTP has been shown to satisfy our definition of a Hebbian synaptic modification. Whether this biophysical mechanism is involved in(More)
Notoplana acticola, a free-living polyclad flatworm, has a small but well-defined brain that controls behavior of peripherally based motoneurones. This is the most primitive brain currently being studied electrophysiologicaly, but little is known of its cytoarchitecture. Using a modified rapid Golgi method, we have investigated neurone configurations within(More)
The manner in which the circuitry of the amygdala computes its suspected mnemonic functions has been a mystery, partly because the cytoarchitectual complexity of this nuclear group has impeded the necessary cellular analysis. Here we report in vitro methods and results that may help elucidate cellular learning mechanisms in amygdala neurons. The amygdala(More)
Video-enhanced contrast, differential-interference contrast microscopy (VEC-DICM) was used to visualize the cytoarchitecture and subcellular neuronal structure of acute brain slices from rat hippocampus and amygdala. Even at low-power magnification, the VEC-DICM system vastly improved our ability to visualize and examine the gross organization of the(More)
In Notoplana avoidance behavior is lost after bisection of the brain or removal of one of its lobes. Behavioral recovery usually occurs within 3-10 days. Recovery of individuals may be gradual or abrupt. Grouped data shows gradual linear repair of turning behavior. Most animals with all connectives between the two lobes of the brain severed recovered(More)
1. Influx of14C-labeled serine and leucine into axenic larvae ofStrongylocentrotus purpuratus occurs from substrate concentrations as low as 125 nmolar. The relation between substrate concentration and the rate of influx has the form of a rectangular hyperbola and is well described by the Michaelis-Menten equation. The apparent kinetic constantsJ i max andK(More)
  • 1