A functional MRI study of face recognition in patients with prosopagnosia

Department of Psychology, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
Neuroreport (Impact Factor: 1.52). 07/2001; 12(8):1581-7. DOI: 10.1097/00001756-200106130-00014
Source: PubMed


An fMRI investigation was conducted to determine whether patients with impaired face recognition, a deficit known as prosopagnosia, would show functional activation in the fusiform gyrus, the neural substrate for face processing, when viewing faces. While the patients did show activation in the fusiform gyrus, with significantly more voxels in posterior areas than their control subjects, this activation was not sufficient for face processing. In one of the patients, the posterior activation was particularly evident in the left hemisphere, which is thought to be involved in feature-based strategies of face perception. We conclude that an increased reliance on feature-based processing in prosopagnosia leads to a recruitment of neurons in posterior regions of the fusiform gyrus, regions that are not ideally suited for processing faces.

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Available from: Jonathan J Marotta
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    • "After a lesion sustained in adulthood (except for CR who was aged 16 years at lesion onset), all individuals reported visual perceptual problems. Table 1 summarizes the patients' case descriptions ; more detailed information is available in the Supplementary material and in previous publications (SM: Gauthier et al., 1999; Marotta et al., 2001; Behrmann and Kimchi, 2003; Behrmann and Williams, 2007; Nishimura et al., 2010; Konen et al., 2011; Behrmann and Plaut, 2013; CR: Gauthier et al., 1999; Marotta et al., 2001; Behrmann and Williams, 2007; Behrmann and Plaut, 2013; EL: Behrmann et al., 1998; Montant and Behrmann, 2001; McKeeff and Behrmann, 2004; Mycroft et al., 2009; Behrmann and Plaut, 2013; GB: Behrmann and Plaut, 2013). Aside from EL, who has an upper right visual field quadrantanopia, the other patients all have full visual fields. "
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    • "CR has full visual fields but his performance is in the " severely impaired " range on the Benton Facial Recognition tests (scores of 36/54), and he is unable to recognize pictures of any famous people (e.g., Bill Clinton). CR has participated in previous studies (Gauthier, Behrmann et al. 1999; Marotta, Genovese et al. 2001; Behrmann and Williams 2007; Humphreys et al. 2007). Although a clearer analysis of the lesion site of patients with pure alexia and with prosopagnosia would be useful, we were unable to do this—most of our patients had clinical scans acquired under different conditions (different scanners, different intensity values), precluding a thorough analysis of the lesion site and size. "
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    • "The neural processing of faces is a widely researched topic of cognitive science. Based on functional imaging studies, single-cell recordings, and neuropsychological research it has been suggested that face-processing is performed by a distributed network, involving several cortical areas of the mammalian brain (Haxby et al., 2000; Marotta et al., 2001; Rossion et al., 2003a; Avidan et al., 2005; Sorger et al., 2007). While the extent of this face-processing network is currently under intensive debate (Ishai, 2008; Wiggett and Downing, 2008) most researchers agree that there are numerous cortical areas activated by face stimuli. "
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