Representational demands modulate involvement of perirhinal cortex in face processing

Abstract

The classic view holds that the medial temporal lobes (MTL) are dedicated to declarative memory functioning. Recent evidence, however, suggests that perirhinal cortex (PrC), a structure within the anterior MTL, may also play a role in perceptual discriminations when representations of complex conjunctions of features, or of gestalt-characteristics of objects must be generated. Interestingly, neuroimaging and electrophysiological recordings in nonhuman primates have also revealed a face patch in the anterior collateral sulcus with preferential responses to face stimuli in various task contexts. In the present fMRI study, we investigated the representational demands that influence PrC involvement in different types of judgments on human faces. Holding stimulus complexity constant, we independently manipulated the nature of the task and the orientation of the stimuli presented (through face inversion). Aspects of right PrC showed increased responses in a forced-choice recognition-memory and a perceptual-oddity task, as compared to a feature-search task that was included to probe visual detection of an isolated face feature. Effects of stimulus orientation in right PrC were observed when the recognition-memory condition for upright faces was compared with all other experimental conditions, including recognition-memory for inverted faces-a result that can be related to past work on the role of PrC in object unitization. Notably, both effects in right PrC paralleled activity patterns in broader networks of regions that also included the right fusiform gyrus and the amygdala, regions frequently implicated in face processing in prior research. As such, the current findings do not support the view that reference to a prior study episode clearly distinguishes the role of PrC from that of more posterior ventral visual pathway regions. They add to a growing body of evidence suggesting that the functional role of specific MTL structures may be best understood in terms of the representations that are required by the task and the stimuli at hand.

Spatio-temporal dynamics and laterality effects of face inversion, feature presence and configuration, and face outline

“…Even though we did not manipulate repetition in a condition-specific manner, the present results are consistent with the idea that this deflection may reflect access to recognition units and activation of a memory trace for the particular face that has become familiar with repetition (Zimmermann and Eimer, 2013). Our localization estimates and the observation of the sensitivity of the inferior and anterior temporal cortices to face orientation and identity are supported by fMRI studies (Sugiura et al, 2001; Rotshtein et al, 2005; Kriegeskorte et al, 2007; Nasr and Tootell, 2012; O'Neil et al, 2013) and are further confirmed with single cell recordings in non-human primates (Freiwald and Tsao, 2010). Similarly, lesion studies report that anterior temporal lesions result in face recognition impairments (Glosser et al, 2003; Barton, 2008; Gainotti and Marra, 2011).…”

Beyond the FFA: The role of the ventral anterior temporal lobes in face processing

“…Several imaging studies have suggested that the human homologue to the monkey anterior face patch is located in the anterior (rostral) collateral sulcus in an area consistent with the PrC (O'Neil, Hutchison, McLean, & Kohler, 2014; Nasr & Tootell, 2012; Rajimehr et al, 2009; Rossion, Hanseeuw, & Dricot, 2012; Tsao et al, 2008). In humans, PrC activations are enhanced for faces relative to other objects (Lee, Bussey, et al, 2005; Lee, Scahill, & Graham, 2008), and face-specific activity in the PrC closely mirrors other face selective areas of the ventral stream (O'Neil, Barkley,& Köhler, 2013). Furthermore, the electrocorticogram of a patient with subdural grid electrodes in the right vATLs revealed a strong face-specific response from an electrode in perirhinal cortex that was reflected in both event-related potentials and broadbannd power changes (Tanji, Iwasaki, Nakasato, & Suzuki, 2012).…”

Neural microgenesis of personally familiar face recognition

“…The perirhinal cortex, which codes feature conjunctions viewpoint-invariantly (91), is involved in complex visual discrimination (92,93) and has been proposed as an extension of the representational hierarchy in the ventral system (94)(95)(96)(97)(98). These characteristics, along with the anatomical location of the perirhinal cortex, render this structure ideally situated to link perception and semantic memory, as required for generation and maintenance of face representations for face individuation (26) and face discrimination across different viewpoints (30,31,99). Our finding of familiarity-related activation increases in the hippocampus mirrors findings suggesting the hippocampus's role in activating preexisting knowledge about faces (100).…”

“…Such extended regions include structures within the medial temporal lobe (MTL), including the hippocampus, perirhinal cortex and amygdala (11,(23)(24)(25)(26)(27), the latter two of which exhibit face-preferential responses (15,28,29).…”

“…Although the hippocampus and perirhinal cortex are traditionally considered to mediate explicit recollection based on episodic memory and diffuse feelings of familiarity, recent studies indicate that these regions are also involved in visual discrimination (26,(29)(30)(31)(32)(33). Furthermore, various studies have also reported anterior ventral temporal activation for familiar (famous) face recognition (11), discrimination of familiar from unfamiliar faces (34)(35)(36)(37)(38) and face naming (39).…”