The human dorsal hippocampal commissure. An anatomically identifiable and functional pathway.

摘要: The hippocampal commissural system in the human brain was found to be similar that of non-human primates. Three normal serially sectioned brains were studied coronal and sagittal sections. Morphological criteria had been validated experimental studies on commissures monkeys (Amaral et al., 1984; Demeter 1985; Lamantia Rakic, 1990) applied study these brains. It while a further reduction ventral commissure has taken place phylogeny leading its near or total disappearance, dorsal is well developed represents sizable fibre tract. crosses midline under rostral portion splenium caudal part body corpus callosum. Its fibres as they travel between formation attach themselves fornix inferior forceps major In morphology fully conforms reported tracer monkey 1985). Depth electrode EEG recordings temporal lobe seizures show, some instances, pattern contralateral spread which strongly suggests it occurred through commissure. This statement based careful analysis different patterns seizure discharge light known anatomical connections mesial structures both direct pathways possible indirect ones involving subcortical frontal lobe. For discharges originating one side with hippocampus before any involvement isocortex only likely pathway propagation. Alternative routes appear unlikely primate anatomy other Thus humans, despite claims contrary (Wilson 1987, 1990, 1991), seem possess functional Some observed this utilize may relevant for two phenomena are clinical interest: (i) pure amnestic (Palmini 1992); (ii) false lateralization onset extracranial type III defined study.