Re:TheAshLad - Sandbooks

that the functional. asymmetries described thus far indicate a
fundamental difference in. the basic cognitive processes of the left and
right cerebral. hemispheres. Howeverbefore turning to this matterwe
will consider a. summary of the databecause any theoretical statements
are best. considered in light of available information. Table below
summarizes. the major data on cerebral lateralization and illustrates the
range of. functions lateralized principally n the left and right
hemispheres.In. righthanded peoplethe left hemisphere has a greater
role in language. and in the control of complex voluntary movements
than does the. right hemisphereand the right hemisphere has a greater
role in the. control of certain visuospatial and nonverbal abilities..
Table. Summary of data on cerebral lateralization. Function Left
hemisphere Right hemisphere. Visual system Letters words Complex
geometric patterns. Faces. Auditory system Languagerelated
Nonlanguage environmental sound. sound Music. Somatosensory
Tactile recognition of complex. system patterns Braille. Movement
Complex voluntary Movements in spatial patterns. movement. Memory
Verbal memory Nonverbal memory. Language Speech Prosody.
Reading. Writing. Arithmetic. Spatial Geometry. processes Sense of
direction. Mental rotation of shapes. A truly enormous number of
proposals have been made on what is. lateral ized in the brain (see
Allen for a readable summary).At the. broadest level these theories fall
into two groupsspecialization. theories propose unique functions for
each hemisphereand interaction. theories propose cooperation between
the two hemispheres.. Several authors (for exampleEfron)have
suggested that it is not. motor control itself that is located in the left
hemisphere but rather. the capacity for the fine resolution of stimuli in
time.In other. wordsbecause the analysis and production of speech
require fine. discrimination over very short intervalsthe left hemisphere
might be. specialized for temporal sequencing (organizing be havior or.
information or both over time).Elaborations of this idea have stressed.
the capacity of the left hemisphere to make fine discriminations in.
timewhether or not the stimuli are verbal (seefor.
exampleSergent).Recall the study of Morsecode operators discussed.
earlierthere is a lefthemisphere advantage even though the code is. not
verbal it is a temporal sequence. Zatorre and his colleagues. expanded
the Efron timing idea by emphasizing that speech and musical. sounds
exploit different acoustical cuesspeech is highly dependent on. rapidly
changing broadband soundswhereas tonal pat terns of music. tend to be
sloweralthough small and precise changes in fre quency. are
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