title: Temporal lobe contribution to perceptual function: A tale of three patient groups.
abstract: There has been growing recognition of the contribution of medial and anterior temporal lobe structures to non-mnemonic functions, such as perception. To evaluate the nature of this contribution, we contrast the perceptual performance of three patient groups, all of whom have a perturbation of these temporal lobe structures. Specifically, we compare the profile of patients with focal hippocampal (HC) lesions, those with more extensive lesions to the medial temporal lobe (MTL) that include HC and perirhinal cortex (PrC), and those with congenital prosopagnosia (CP), whose deficit has been attributed to the disconnection of the anterior temporal lobe from more posterior structures. All participants completed a range of'oddity' tasks in which, on each trial, they determined which of four visual stimuli in a display was the'odd-one-out'. There were five stimulus categories including faces, scenes, objects (high and low ambiguity) and squares of different sizes. Comparisons were conducted separately for the HC, MTL and CP groups against their matched control groups and then the group data were compared to each other directly. The group profiles were easily differentiable. Whereas the HC group stood out for its difficulty in discriminating scenes and the CP group stood out for its disproportionate difficulty in discriminating faces with milder effects for scenes and high ambiguity objects, the MTL group evinced a more general discrimination deficit for faces, scenes and high ambiguity objects. The group differences highlight distinct profiles for each of the three groups and distinguish the signature perceptual impairments following more extended temporal lobe alterations. In the recent reconsideration of the role of the hippocampus and neocortex, Moscovitch and colleagues (Moscovitch et al., 2016) note that the medial temporal lobe structures play a role in non-mnemonic functions, such as perception, problem solving, decision-making and language. Here, we address this exact issue, specifically with respect to perception, and we dedicate this paper to Morris Moscovitch in recognition of his profound contribution to science, to his students and to his colleagues.
authors.affiliation: Department of Psychology and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh PA 15213-3890, United States. Electronic address: behrmann@cmu.edu.
authors.forename: M
authors.initials: M
authors.lastname: Behrmann
authors.affiliation: Rotman Research Institute, Toronto, ON, Canada M6A 2E1; Department of Psychology (Scarborough), University of Toronto, Toronto, ON, Canada M1C 1A4.
authors.forename: A C H
authors.initials: AC
authors.lastname: Lee
authors.affiliation: Department of Psychology and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh PA 15213-3890, United States.
authors.forename: J Z
authors.initials: JZ
authors.lastname: Geskin
authors.affiliation: Cardiff University Brain Research Imaging Centre and School of Psychology, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK.
authors.forename: K S
authors.initials: KS
authors.lastname: Graham
authors.affiliation: Rotman Research Institute, Toronto, ON, Canada M6A 2E1; Department of Psychology (St George), University of Toronto, Toronto, ON, Canada M5S 3G3.
authors.forename: M D
authors.initials: MD
authors.lastname: Barense
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001930:Brain Injuries / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D016022:Case-Control Studies; D004192:Discrimination, Psychological; D005260:Female; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010468:Perceptual Disorders / Q000209:etiology / Q000473:pathology; D010775:Photic Stimulation; D020238:Prosopagnosia / Q000151:congenital* / Q000000981:diagnostic imaging / Q000473:pathology; D021641:Recognition, Psychology; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014796:Visual Perception / Q000502:physiology*
keywords: Amnesia; Congenital prosopagnosia; Hippocampus; Medial temporal lobe; Perception; Perirhinal cortex; Visual discrimination