Autonomic and somatic responses associated with performance of the picture completion test
Heart rate, respiration rate, and chin electromyographic activity were monitored while 30 female subjects performed a modified version of the Picture Completion Test. The heart rate results suggested that the following may be predictive of correctly solving the test stimuli: an anticipatory deceleration in heart rate just prior to stimulus onset; higher heart rates during stimulus presentation; and greater amounts of heart rate fluctuation prior to stimulus onset. Only a few parallels were noted between the heart rate data and the results for the somatic- muscular variables. Specifically, the respiration results indicated that among stimuli presented without warning, higher respiration rates were observed during the presentation of correctly solved stimuli than during incorrectly solved stimuli. Also, the chin electromyographic activity results revealed greater amounts of chin EMG activity during the latter portion of stimulus presentation for correctly solved stimuli as compared to incorrectly solved stimuli. The results were consistent with the Laceys' hypothesis regarding the relationship between heart rate changes and attention. However, only limited support was provided for Obrist's contention that changes in heart rate are coupled to somatic-muscular responses.