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F J McGuigan

Publications and source records attributed to F J McGuigan.

At least 19 recordsLinked to original sources
PubMed1995

An auditory event related potential evaluation of sonar task experience and age.

To gauge the interaction of real-world sonar-task experience and age on brain electrical activity, the effect of sonar experience and age on event related potentials (ERP) was examined. A three-group design was used and the results suggest that sonar experience and age affect the amplitude and distribution of the ERP component. The results concerning age and ERPs support and extend the results of previous studies and suggest that age-related differences occur at a much younger age than is reported elsewhere. Attentional and stimulus evaluation processes which have been linked to parameters of the ERP component may be enhanced with real-world auditory task experience. Research on ERP should control for the possible confounds of auditory-task experience and age.

Adolescent↗
PubMedDate not supplied

Patterns of covert speech behavior and phonetic coding.

In previous research a discriminative relationship has been established between patterns of covert speech behavior and the phonemic system when processing continuous linguistic material. The goal of the present research was to be more analytic and pinpoint covert neuromuscular speech patterns when one processes specific instances of phonemes. Electromyographic (EMG) recording indicated that the lips are significantly active when visually processing the letter "P"(an instance of bilabial material), but not when processing the letter "T" or a nonlinguistic control (C) stimulus. Similarly, the tongue is significantly active when processing the letter "T" (an instance of lingual-alveolar material), but not when processing the letters "P" or "C". It is concluded that the speech musculature covertly responds systematically as a function of class of phoneme being processed. These results accord with our model that semantic processing ("understanding") occurs when the speech (and other) musculature interacts with linguistic regions of the brain. In the interactions phonetic coding is generated and transmitted through neuromuscular circuits that have cybernetic characteristics.

Afferent Pathways↗
PubMedDate not supplied

Frequency analysis of electromyographically measured covert speech behavior.

Eleven subjects were asked to silently read slides of the letters "P" and "T," and to view meaningless control slides similarly as they were presented visually. One-eighth-second electromyographic excerpts were sampled from the baseline and response periods. The data were then transformed into the frequency domain for inferential analyses. The mean power spectral frequencies for the response period were significantly lower than those for the base-line in the overall analysis. There were, however, no significant changes from baseline as a function of kind of stimulus (T, P, or Control) or muscle activated (lips or tongue). It was concluded that there was a generalized responding, not unique to the processing of the specific stimuli studied. Frequency analysis of EMG measures of covert behavior holds some promise of yielding unique information not available through traditional analysis procedures, but more sensitive methods than those used here would be required to demonstrate this.

Afferent Pathways↗