How much do neural systems vary between individuals?
An interesting article in J Neurosci from Eve Marder’s group on the variability of a neural system (in this case, lobster stomatogastric ganglion) between individuals. In the STG, they found no difference between adults and juvenile. (In lobsters, the adult is about 10X the size of the juvenile.) Also, between different adults, the waveforms displayed variability in frequency and bursts per peak but the phase relationships between specific neurons was the same.
To me, this work seems very exciting as I am not aware of much literature on saying *what* biological/neurophysiological phenomena are important in determining behavior (eg. individual spikes, synchronicity, Ca, dendritic effects, etc.) Of course, I don’t really know this literature in great depth…
Read on for the abstract.
J Neurosci. 2005 Feb 16;25(7):1611-9.
Animal-to-animal variability in motor pattern production in adults and during growth.
Bucher D, Prinz AA, Marder E.
Volen Center and Biology Department, Brandeis University, Waltham, Massachusetts 02454-9110, USA. bucher@brandeis.edu
Which features of network output are well preserved during growth of the nervous system and across different preparations of the same size? To address this issue, we characterized the pyloric rhythms generated by the stomatogastric nervous systems of 99 adult and 12 juvenile lobsters (Homarus americanus). Anatomical studies of single pyloric network neurons and of the whole stomatogastric ganglion (STG) showed that the STG and its neurons grow considerably from juvenile to adult. Despite these changes in size, intracellularly recorded membrane potential waveforms of pyloric network neurons and the phase relationships in the pyloric rhythm were very similar between juvenile and adult preparations. Across adult preparations, the cycle period and number of spikes per burst were not tightly maintained, but the mean phase relationships were independent of the period of the rhythm and relatively tightly maintained across preparations. We interpret this as evidence for homeostatic regulation of network activity.