Electrophysiological and behavioral evidence of adaptive functions in the orbitofrontal cortex

Abstract

The orbitofrontal cortex (OBF) plays important role in the organization of adaptive behavior. To further characterize these functions, complex electrophysiological-neurochemical-behavioral experiments were performed in rats and rhesus monkeys. Single neuron activity was recorded in the OBF 1) during feeding or sexually motivated visual discrimination tasks, 2) microiontophoresis of neuroactive substances, i.e. glucose, catecholamines and other neurochemicals and 3) during gustatory stimulations. OBF neurons responded to various microiontophoretically administered chemicals as well as to gustatory stimulations in both species showing complex chemosensory attributes. In the monkey OBF, feeding or sexual behavior related characteristic firing rate changes were recorded. Our results indicate that OBF possesses specific endo- and exogenous chemosensitivity and it is involved in behavioral responses as well utilizing differential neurotransmitter mechanisms in integrative processes of adaptive behavior. Supported by: 21st Century COE program and Grants-in-Aid for Scientific Research (S.A.), NKTH MEDIPOLIS RET-008/2005, ETT (315/2006), National Research Fund of Hungary (T042721, M036687), and the HAS (L.L.). [J Physiol Sci. 2007;57 Suppl:S163]