Impaired spatial working memory on a T-maze after MSDB Na_v1.1 knockdown.

<p>(A) Schematic of T-maze apparatus used for working memory task. Rats were trained to run from the start box to the end arm to receive a food reward. On each test trial, rats were given a Sample run (a forced turn either left or right), followed by a variable delay period, and then a Choice run. Correct choices required the rat to remember and recall the direction it had travelled on the Sample run and to then choose the opposite direction on the Choice run. (B) Mean choice accuracy for all trials was significantly worse with knockdown of Na_v1.1 compared to controls (p<.01). (C) Choice accuracy segregated into 24-trial blocks. Performance was initially lower for both groups during ‘variable delay’ trials, but performance improved in controls and not in shScn1a rats. (D) Choice accuracy segregated by delay length (short, 15-30s; long, 60s). While performance was lower overall for shScn1a rats, they were substantially worse at the longest delay, performing no better than chance levels. Data show mean +/- SEM. *p<.05, **p<.01.