The concept of extended amygdala in information processing within dopaminergic circuits

THE CONCEPT OF EXTENDED AMYGDALA IN INFORMATION PROCESSING WITHIN DOPAMINERGIC CIRCUITS 

Both the medial and the central divisions of the extended amydala receive dopaminergic innervation from all the midbrain dopaminergic cells groups (A8, A9 and A10) the medial extended amygdala projects to the VTA, and the circuits efferent from the central extended amygdala also target the VTA, as well as the RRA (Alheid et al., 1995 De Olmos et al., 2004) (Fig. 19). 

The striatopallidal system and the extended amygdala have similar but also distinct and complementary chemical signatures (Alheid, 2003). On this basis, as well as on the basis of distinct circuitry, the extended amygdala is recognized as an entity independent from the 

The dopaminergic fibers which innervate diencephalic structures will be dealt with here briefly, since most of the diencephalic DA-containing system is related to the dopaminergic cell groups of the hypothalamus, which are the subject of the chapter of Lookingland and Moore in this volume. The dopaminergic innervation of the STh was dealt with above in Section 6.2. 

In the diencephalon, besides the hypothalamus, dopaminergic fibers have also been detected in the thalamic nuclei and in the habenula. It is interesting to note that in the thalamus dopaminergic fibers are distributed to nuclei that are also recipient of inputs from the ventral pallidum. 

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