[Thalamus and Emotion].

The basolateral limbic circuit (mediodorsal thalamic nucleus, anterior cingulated and prefrontal orbital cortex, anterior temporal cortex, and amygdala), the mediodorsal thalamic nucleus circuit, and part of the frontal-subcortical circuits (anterior cingulate and prefrontal orbital cortex, caudate nucleus and nucleus accumbens, globus pallidus, and mediodorsal thalamic nucleus), and the anterior cingulate and prefrontal orbital cortex circuit are crucial systems for forming and expressing emotions. There are reciprocal projections between the hypothalamus, anterior cingulate cortex and prefrontal orbital cortex, and between the hypothalamus and the amygdale. Therefore, destruction of the mediodorsal thalamic nucleus and the hypothalamus can cause abnormal expression of emotions. Recently, converging evidence suggests that the pulvinar nucleus in the posterior thalamus mediates emotional visual information processing through the colliculo-pulvino-amygdalar pathway and/or through the colliculo-pulvino-cortical pathways. These pathways seem to contribute to the unconscious and/or conscious fast processing of ecologically relevant stimuli. Therefore, destruction of the pulvinar can cause impaired reaction to visual threats, such as photographs of a cockroach and fearfull facial expressions, if the stimuli are exposed briefly.