THE LATERAL AND MEDIAL COMPARTMENTS OF THE OLFACTORY TUBERCLE AND THEIR RELATION TO OLFACTORY-RELATED INPUT AS DETERMINED BY ARTIFICIAL NEURAL-NETWORK ANALYSIS
E. Josephson et al., THE LATERAL AND MEDIAL COMPARTMENTS OF THE OLFACTORY TUBERCLE AND THEIR RELATION TO OLFACTORY-RELATED INPUT AS DETERMINED BY ARTIFICIAL NEURAL-NETWORK ANALYSIS, Brain research, 744(2), 1997, pp. 253-271
The current literature indicates that olfactory bulbar input projects
throughout layer IA of the entire olfactory tubercle, with apparently
more fibers in the lateral part than in the medial part of the tubercl
e. In addition, olfactory cortical association fibers project to layer
s IB, II, and III in all regions of the tubercle. This study exploited
the phenomenon of transsynaptic transfer of WGA-HRP after injection i
nto the olfactory bulb of rats to explore the degree of olfactory-rela
ted input to the tubercle. A computerized image analysis system was em
ployed to quantify the amount of tracer transferred to layer II neuron
s of the tubercle. Qualitative analysis of the data indicates that the
lateral tubercle consists of areas that receive little olfactory-rela
ted input. Nonparametric statistical tests and a novel application of
artificial neural networks indicate regionally heterogeneous labeling
across the tubercle and broad connections between homologous regions o
f the bulb and tubercle. These results have implications for understan
ding how olfactory sensory information is integrated into limbic-motor
circuits by the olfactory tubercle.