Article

Neural Substrates of Phonemic Perception

Department of Neurology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
Cerebral Cortex (Impact Factor: 8.67). 11/2005; 15(10):1621-31. DOI: 10.1093/cercor/bhi040
Source: PubMed

ABSTRACT

The temporal lobe in the left hemisphere has long been implicated in the perception of speech sounds. Little is known, however,
regarding the specific function of different temporal regions in the analysis of the speech signal. Here we show that an area
extending along the left middle and anterior superior temporal sulcus (STS) is more responsive to familiar consonant–vowel
syllables during an auditory discrimination task than to comparably complex auditory patterns that cannot be associated with
learned phonemic categories. In contrast, areas in the dorsal superior temporal gyrus bilaterally, closer to primary auditory
cortex, are activated to the same extent by the phonemic and nonphonemic sounds. Thus, the left middle/anterior STS appears
to play a role in phonemic perception. It may represent an intermediate stage of processing in a functional pathway linking
areas in the bilateral dorsal superior temporal gyrus, presumably involved in the analysis of physical features of speech
and other complex non-speech sounds, to areas in the left anterior STS and middle temporal gyrus that are engaged in higher-level
linguistic processes.

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    • "For example, one might monitor the color of a steak on a barbeque to determine when it is cooked to perfection or the facial expression of a partner to determine if the mood has shifted. These decisions may be categorical (Liberman et al., 1957; Liebenthal et al., 2005; Hardendorp et al., 2010), and can be critical for social interaction and even survival (Grinband, 2006; Calder et al., 1996; Etcoff and Magee 1992; McCullough and Emmorey, 2009). But while the answers can be categorical, the stimuli they depend on vary continuously (e.g., the color of the meat; slight shifts in the curve of a lip). "

    Full-text · Dataset · Nov 2015
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    • "For example, one might monitor the color of a steak on a barbeque to determine when it is cooked to perfection or the facial expression of a partner to determine if the mood has shifted. These decisions may be categorical (Liberman et al., 1957; Liebenthal et al., 2005; Hardendorp et al., 2010), and can be critical for social interaction and even survival (Grinband, 2006; Calder et al., 1996; Etcoff and Magee 1992; McCullough and Emmorey, 2009). But while the answers can be categorical, the stimuli they depend on vary continuously (e.g., the color of the meat; slight shifts in the curve of a lip). "

    Full-text · Dataset · Nov 2015
  • Source
    • "For example, one might monitor the color of a steak on a barbeque to determine when it is cooked to perfection or the facial expression of a partner to determine if the mood has shifted. These decisions may be categorical (Liberman et al., 1957; Liebenthal et al., 2005; Hardendorp et al., 2010), and can be critical for social interaction and even survival (Grinband, 2006; Calder et al., 1996; Etcoff and Magee 1992; McCullough and Emmorey, 2009). But while the answers can be categorical, the stimuli they depend on vary continuously (e.g., the color of the meat; slight shifts in the curve of a lip). "
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