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Face Expertise and Category Specialization in the Human Occipitotemporal Cortex
Published in Jon H. Kaas, Christine E. Collins, The Primate Visual System, 2003
The neural source of the N170 is unclear, as is its relationship to the face-sensitive regions identified in fMRI, even though ERPs reflect essentially postsynaptic activity that is likely to be the source of the BOLD signal used in fMRI.69 The fMRI signal is measured over several seconds whereas the N170 reflects transient changes of electrical potential on the order of a few tenths of milliseconds. More than a dozen areas are likely to show activity between 100 and 200 ms following the presentation of a visual complex stimulus such as a face, with several showing differential activation to faces and objects. Therefore, the N170 is likely to reflect the combination of several generators with different orientations, active around this latency. Several local electrophysiological components responsive to faces (or to objects) such as the N200 are recorded on a multitude of sites in intracranial recordings along the ventral and lateral parts of occipitotemporal cortex.70 Most of these local components are likely to contribute to the far-field N170 scalp potential. For this reason, functional links between the scalp ERPs such as the N170 and the activity of face-sensitive regions in fMRI may be the only meaningful approach.
Inefficient integration during multiple facial processing in pre-morbid and early phases of psychosis
Published in The World Journal of Biological Psychiatry, 2022
TianHong Zhang, YingYu Yang, LiHua Xu, XiaoChen Tang, YeGang Hu, Xin Xiong, YanYan Wei, HuiRu Cui, YingYing Tang, HaiChun Liu, Tao Chen, Zhi Liu, Li Hui, ChunBo Li, XiaoLi Guo, JiJun Wang
Very few studies have examined both facial recognition and facial emotion processing in the same study. As described above, facial recognition, which is a component of facial processing, is demonstrably impaired in patients with schizophrenia (Kohler et al. 2010; Savla et al. 2013). Event-related potential (ERP) measurements have been widely used to explore the mechanisms underlying face processing. ERP components such as N170 are thought to reflect the early visual processing responsible for constructing a representation of the human face (Vuilleumier and Pourtois 2007; Shah et al. 2018). Many studies have found that N170 tends to have a larger amplitude in response to face stimuli than to other stimuli such as objects. A recent meta-analysis of patients with schizophrenia (McCleery et al. 2015) showed that the amplitude of N170 to face stimuli was smaller in patients than in HCs. However, face stimuli in most schizophrenia studies were designed as single and isolated images, which is a very unrealistic situation compared to what is encountered socially on a daily basis.
Uncoupled Brain and Behavior Changes in Lexical, Phonological, and Memory Processing in Struggling Readers
Published in Developmental Neuropsychology, 2021
First, we considered isolated word and nonword reading, for which fluency is dependent on automaticity (e.g., Adams, 1990). Previous behavioral studies have indicated the potential for plasticity in struggling readers: Phonics training improves real word and nonword reading fluency in poor readers, with comparatively weaker evidence for accuracy (e.g., see McArthur et al., 2018). Two components in the event-related potential (ERP) waveform have specifically been associated with word and nonword processing: the N170, which indexes orthographic tuning for word stimuli in the visual word form area (e.g., Maurer et al., 2007; McCandliss, Cohen, & Dehaene, 2003), and the N400, which indexes interactive word processing at multiple levels of representation including orthography and semantics (e.g., Coch & Holcomb, 2003; Laszlo & Federmeier, 2011).
Low Spatial Frequency Sensitivity and Emotional Face Processing in Adolescents: An Event-related Potential Study
Published in Developmental Neuropsychology, 2020
Jillian Grose-Fifer, Max Lobel, Danielle diFilipo, James Gordon
Some studies have shown that the N170 is differentially modulated by emotional facial expressions. A meta-analysis of 57 studies including 1,645 adults found that the N170 is generally larger for angry, fearful, and happy faces compared to neutral expressions, although this effect was found to vary with task demands, with larger effects for tasks where emotion was implicitly processed compared to those where explicit recognition was required (Hinojosa, Mercado, & Carretié, 2015). Fearful faces elicit longer latency N170s than neutral or positive faces in children as young as 4 years old, and putative precursors of the N170 (N290 and P400) have been shown to be sensitive to emotional expression during infancy (e.g. van den Boomen, Munsters, & Kemner, 2019). However, FEP effects on N170 amplitude are not thought to emerge until 14–15 years (Batty & Taylor, 2006).