Dissociation of the neural substrates of foraging effort and its social facilitation in the domestic chick.

摘要: Abstract The frequency or intensity of behavior is often facilitated by the presence others. This social facilitation has been reported in a variety animals, including birds and humans. Based on Zajonc’s “drive theory,” we hypothesized that drive have shared neural mechanisms, dopaminergic projections from midbrain to striatum are involved. As ascending include mesolimbic nigrostriatal pathways, targeted our lesions at medial (MSt) substantia nigra (SN). We found bilateral electrolytic lesion MSt suppressed baseline foraging effort, but was intact. Conversely, an unilateral SN (on right side) partially facilitation, while effort remained unaffected. However, selective depletion catecholaminergic (thyrosine hydroxylase immunoreactive) terminals micro-infusion 6-hydroxydopamine (6-OHDA) had no significant effects behavior, whereas it impaired formation association memory reinforced water reward. Neurochemical assay high-perfromance liquid chromatography also revealed decrease dopamine noradrenaline contents after 6-OHDA compared with intact control chicks. Thus, conclude substrate can be dissociated responsible for reward-based pathways do not appear contribute facilitation. detailed analysis areas, discuss fiber tracts components tegmental area may