Brain stem auditory evoked responses during the cold pressor test

This study was conducted to determine changes, if any, in Brain stem auditory evoked responses (BAEP's) during the cold pressor test (CPT) in healthy human subjects. Thirteen subjects (age 18-25 yrs) were selected for the study. Their BAEP's were recorded using standardized technique employing 10-20 international electrode placement system and sound click stimuli of specified intensity, duration and frequency. The standard CPT was performed in the non-dominant hand and the BAEP's, heart rate and blood pressure were recorded before and during the CPT. The values of absolute peak latencies and amplitude of evoked responses were statistically analysed. The amplitude of wave V showed a significant increase (P < 0.05) during the CPT (0.47 +/- 0.203 and 0.37 +/- 0.174 mu v before and during CPT respectively). This could be due to interaction of activated central ascending monoaminergic pathways or nociceptive afferents with the midbrain auditory generator so as to increase it's activity.