The influence of familiarity on brain activation during haptic exploration of 3-D facemasks

Little is known about the neural substrates that underlie difficult haptic discrimination of 3-D within-class object stimuli. Recent work [A.R. Kilgour, R. Kitada, P. Servos, T.W. James, S.J. Lederman, Haptic face identification activates ventral occipital and temporal areas: an fMRI study, Brain Cogn. (in press)] suggests that the left fusiform gyrus may contribute to the identification of facemasks that are haptically explored in the absence of vision. Here, we extend this line of research to investigate the influence of familiarity. Subjects were trained extensively to individuate a set of facemasks in the absence of vision using only haptic exploration. Brain activation was then measured using fMRI while subjects performed a haptic face recognition task on familiar and unfamiliar facemasks. A group analysis contrasting familiar and unfamiliar facemasks found that the left fusiform gyrus produced greater activation with familiar facemasks.