General and Specific Aversive Modulation of Active Avoidance Require Central Amygdala.

Three studies provide evidence that the central nucleus of the amygdala, a structure with a well-established role in conditioned freezing, is also required for conditioned facilitation of instrumental avoidance in rats. First, the immediate early gene c-Fos was measured following the presentation of a previously shock-paired tone in subjects trained either on an unsignaled avoidance task or not (in addition to tone only presentations in naïve controls). Significantly elevated expression of c-Fos was found in both the avoidance trained and Pavlovian trained conditions relative to naïve controls (but with no difference between the two trained conditions).

Anatomical variation of median nerve: cadaveric study in brachial plexus.

Median nerve is formed by lateral root from lateral cord and medial root from medial cord of brachial plexus. Formation of median nerve occur in front or lateral to axillary artery in axilla. In the present study we observed anatomical variations of median nerve formation in the brachial plexus.