Wheel running behavior is impaired by both surgical section and genetic absence of the mouse corpus callosum.

Mice lacking a corpus callosum (CC) often show little or no deficit on tests of behavior. This paper reports that on highly complex bimanual motor tasks, deficits can be found. The speed of running on a wheel with irregularly spaced rungs is reduced by both hereditary absence of the CC in 129 x BALB/c recombinant mice and surgical section of the CC in genetically normal B6D2F(2) mice.

Increased axon number in the anterior commissure of mice lacking a corpus callosum.

Relatively few behavioral deficits are apparent in subjects with hereditary absence of the corpus callosum (CC). The anterior commissure (AC) has been suggested to provide an extracallosal route for the transfer of interhemispheric information in subjects with this congenital defect. Anterior commissure size, axon number, axon diameter, and neuronal distribution were compared between normal mice and those with complete CC absence.

A precision surgical approach for complete or partial callosotomy in the mouse.

The corpus callosum (CC) of mice was completely transsected with a thin tungsten knife using a three-cut approach through the dorsal cerebrum just lateral to midline. This method results in almost total transsection of the CC throughout its entire rostrocaudal extent. Advantages of this approach include minimal bleeding and extracallosal damage as well as the possibility of selective transsection of only anterior, middle, or posterior parts of the CC.

Prefrontal cortex and the relative associability of taste and place cues in rats.

The effects of cutting the corticocortical connections between medial and sulcal prefrontal areas on the conditioning of taste and place cues were examined. In Experiment 1, rats were simultaneously exposed to taste and place cues before injection of 0.15 M LiCl.

A new hybrid mouse model for agenesis of the corpus callosum.

A three locus model of the inheritance of absent corpus callosum in mice was tested by creating F1 and F2 hybrid crosses from the strains BALB/cWah1 and 129/J which show incomplete penetrance for callosal agenesis. The model predicted that a few of the F2 hybrid mice would suffer severe reduction of the hippocampal commissure when the corpus callosum was absent, a condition that usually occurs only in the most consistently acallosal I/LnJ strain, and this prediction was confirmed. The C129F2 hybrid population expresses substantial genetic variation and an extremely wide range of defects of the corpus callosum, dorsal commissure of the fornix and hippocampal commissure.