EFFECTS OF DIENCEPHALIC LESIONS ON APPROACH RESPONSES AND COLOR PREFERENCES IN QUAIL

The effects of stereotaxic radio-frequency lesions on artificially sel ected approach responses and artificially selected or imprinted red or blue preferences were studied in Japanese quail chicks. No effects we re found from lesions in anterior preoptic or pretectal areas and only slight attenuation of red preferences by lesions in nucleus rotundus, opticus principalis thalami and geniculatus lateralis pars ventralis. Extensive lesions in medial diencephalic and bordering areas of telen cephalon, ansa lenticularis, lateral and medial forebrain bundle dimin ished approach tendencies and greatly attenuated the genetically influ enced red preferences. Medial diencephalic lesions confined to the dor somedial thalamic complex and lateral hypothalamus left approach tende ncies intact but similarly attenuated only red preferences. Imprinted red or blue preferences of a highly imprintable quail line were also a ttenuated; red preference strongly, blue preference moderately. The da ta indicate differential diencephalic mediation of the quail's genetic ally distinct color preferences and suggest diverse subtelencephalic c hannels for mediation of approach responses and stimulus preferences. The results also suggest common neural mediation of genetically determ ined and acquired stimulus preferences.