Figure 3.

Effects of baclofen/muscimol microinfusions into the mediodorsal (MD) and the anterior thalamus (AT) during testing in the five-choice serial reaction time task (5-CSRTT). Attentional deficits resulted from MD infusions, which manifested as a decrease in (a) trials and (b) accuracy and an increase in the (c) percentage responses omitted. (d) Rats in both groups showed a trend to respond prior to stimulus presentation following baclofen/muscimol infusions. Such premature responses are interpreted as an index for impulsivity. Although a main effect of treatment was seen in premature responses, no significant interaction of dose × region was found. (e) The ratio of perseverative responses:correct responses showed no significant difference when comparing treatment groups, indicating that any significant decrease in perseverative responses was likely caused by a decrease in correct responses. (f) Reward collection latency remained intact in both regions following all microinfusions. (g) A main effect of dose was seen on correct response latency, but no significant interaction was found. (h) Incorrect response latency was increased significantly by the high dose in MD infusions with no other significant effects seen for either thalamic regions. Values are shown as mean ± SEM. Significance is denoted as *p <0.05, **p<0.01, ***p<0.001. Significant main effect of dose-only is denoted as ^†p <0.05.