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Biomedical subjects

R Coger

Publications and source records attributed to R Coger.

7 recordsLinked to original sources
PubMed1980

Peripheral fiber correlates to noxious thermal stimulation in humans.

Minimal conduction velocities of peripheral nerves contributing to acute thermal pain sensation in human volunteer subjects were calculated. Purely thermal stimulation was administered by a low power laser beam directed at the subjects' fingers, and subjective pain responses correlated with a peak in the event-related brain potential (ERBP). These cerebral responses were found to preclude C fiber peripheral activity from this phenomenon.

Cerebral Cortex↗
PubMed1980

Single trial analysis of evoked potentials to noxious thermal stimulation in man.

Thermal (laser) evoked responses were obtained from 13 male volunteers. A single trial analysis technique with a latency adjusting adaptive filter was used to analyze evoked response amplitudes. Significant and substantial within-subject linear correlations were found between the magnitude (A) of the primary waveform (RMS muV of the P200--N300-P400 complex ) and subjective pain response (R) as well as stimulus intensity (S). Since subjective pain response was strongly correlated with stimulus intensity, the partial correlation coefficients were calculated for R vs. A with S controlled, and S vs. A with R controlled, for each subject. The partial correlations revealed a much stronger relationship between subjective response and the evoked response amplitude, suggesting that the primary complex may measure neural events in the pain perception process rather than transduction and transmission of the stimulus event.

Computers↗
PubMed1975

Physiological and psychological effects of methadone in man.

Methadone hydrochloride-maintenance outpatients were compared to abstinent exaddicts on physiological and psychological measures, and to normal subjects on physiological measures. The battery of psychological tests measure cognitive abilities and mental state. Methadone depressed respiration rate below other groups; abstinent subjects had higher heart rates than methadone or control subjects. No other physiological differences appeared. Electroencephalographic spectral analysis disclosed that the location of the alpha peak was at the lowest frequency in the methadone group, next lowest being the abstinent group. Discriminant functions based on a weighted combination of variables (frequencies) successfully distinguished the EEGs of the three groups. Both discriminant analysis and multiple regression analysis indicated that EEG changes were dose-dependent. Methadone subjects performed significantly poorer on several tests of learning and immediate recall compared to absitinent subjects.

Administration, Oral↗