2015 Speech and Language

Overview of language

One of the most remarkable functions of the human cortex is the generation and comprehension of language. Language regions of the brain are specialized for symbolic representation of communication. Mapping of cortical regions responsible for language is clinically important as it can give vital information regarding location and extent of damage (particularly following a stroke). In the vast majority of people (i.e., people who are right handed), the primary functions for semantic processing are located in the left hemisphere.

Critical Fact icon
  • Communicationlanguage is a symbol system for the exchange of ideas, and there are 3 overlapping components:
    • comprehension
    • interpretation
    • expression

  • the brain regions involved are a complex, overlapping network that can be dissected only partially in terms of function, but there are brain regions that are specialized for interpretation of language
    • these regions must coordinate with cortical regions responsible for earlier stages of comprehension, and later stages of expression
  Comprehension
(input)
Interpretation of Language Expression
(output)
Spoken Language Listening
(starts in the
auditory system)
Speaking
(ends with muscles controlling the
vocal apparatus)
Written Language Reading
(starts in the
visual system)
Writing
(ends with muscles
controlling the hands)













  • regions of the cortex devoted to interpretation of sign language are generally the same as those that organize spoken and written language, indicating that the "language regions" of the brain are specialized for symbolic representation of communication, rather than being specialized for spoken vs. written language

  • each language has a set of rules that define it, and the brain regions that interpret language are specialized for the understanding of these rules
    • from this perspective, the representation of a language can be defined in terms of rules that:
      • define symbol use (GRAMMAR)
      • organize symbols (SYNTAX)
      • allow emotional emphasis via changes in pitch, intensity and rhythm (PROSODY)
        • note that different languages use prosody differently (English uses pitch, loudness AND timing to convey emotional content; tonal languages such as Mandarin Chinese and Navajo use pitch to convey semantic meaning, reserving loudness and timing for prosody)

  • of course, regions of cortex that are involved with interpretation of language interact with regions involved in numerous other executive functions (such as attention and memory) that can significantly impact the ability to comprehend or express language
    • APROSODY (difficulty in either conveying or understanding the emotional qualities of speech) is one component of the flattened affect characteristically observed in depressed or schizophrenic patients
Email: Dr. Janet Fitzakerley | ©2015 University of Minnesota Medical School Duluth | Last modified: 2-mar-15 9:40 PM