Hippocampus and medial striatum dissociation during goal navigation by geometry or features in the domestic chick: An immediate early gene study

• Published in: Hippocampus 2016-01, Vol.26 (1), p.27-40
• Main Authors: Mayer, Uwe, Pecchia, Tommaso, Bingman, Verner Peter, Flore, Michele, Vallortigara, Giorgio
• Format: Article
• Language: English
• Subjects: Animals; avian hippocampus; Avian Proteins - metabolism; Chickens; Corpus Striatum - metabolism; Discrimination (Psychology) - physiology; feature discriminations; geometric navigation; Goals; Hippocampus - metabolism; Immunohistochemistry; Learning - physiology; Male; medial striatum; Neurons - metabolism; Neuropsychological Tests; Proto-Oncogene Proteins c-fos - metabolism; Reward; spatial cognition; Spatial Navigation - physiology
• ISSN: 1050-9631; 1098-1063
• DOI: 10.1002/hipo.22486

ABSTRACT We employed a standard reference memory task to study the involvement of the hippocampal formation (HF) of domestic chicks that used the boundary geometry of a test environment to orient to and locate a reward. Using the immediate early gene product c‐Fos as a neuronal activity marker, we found enhanced HF activation in chicks that learned to locate rewarded corners using the shape of a rectangular arena compared to chicks trained to solve the task by discriminating local features in a square‐shaped arena. We also analyzed neuronal activity in the medial part of the medial striatum (mMSt). Surprisingly, in mMSt we observed a reverse pattern, with higher activity in the chicks that were trained to locate the goal by local features. Our results identify two seemingly parallel, memory systems in chicks, with HF central to the processing of spatial‐geometrical information and mMSt important in supporting local feature discrimination. © 2015 Wiley Periodicals, Inc.