Figure 5.

EphA7 overexpression is associated with reduced spontaneous multiunit activity, but not sensory-evoked responsiveness, in de-efferented regions of the MGB. Recordings were made from MGBv in controls as well as mice in which EphA7 electroporation hit or missed the Actx (indicated as EphA7-hit and EphA7-miss, respectively). (A) Rastergrams depict firing rate (FR) changes evoked by frequency-modulated sweeps that varied according to their direction (upward = positive, downward = negative) and speed. Spectrograms on the right depict an upward sweep at 80 octaves/s and a downward sweep at 40 octaves/s. (B) Actx EphA7 levels do not affect mean sweep-evoked firing rate. (C) Histograms depict the lack of direction preference overall and the absence of differences in direction preference across the sample of multiunits recorded in control (gray bars), EphA7-hit (black bars), or EphA7-mss (open bars). (D) Spontaneous firing rate was significantly lower in EphA7-hit compared with either control or EphA7-miss recordings. Asterisk indicates P < 0.005 with an unpaired t-test. Bar plots in B and D represent mean ± standard error of the mean.