Biomedical subjects

F Boiten

Publications and source records attributed to F Boiten.

4 recordsLinked to original sources

PubMed1996

Autonomic response patterns during voluntary facial action.

The effects of six voluntarily adopted emotional facial expressions on heart rate, respiration, emotional report, and effort ratings were examined. The results indicate that the facial expressions that were most difficult to produce (anger, fear, and sadness) showed larger cardiac accelerations than those that were easy to produce (disgust and surprise); the happiness expression fell somewhere in between. Emotional self-report revealed that in the majority of the facial configuration trials subjects experienced only moderate or no emotion at all. In addition to the emotional configurations, a nonemotional expression was examined. Post hoc comparisons showed that the heart rate data of the nonemotional face were not significantly different from any of the other emotional expressions. With respect to respiration, the production of facial expressions induced an increase in functional residual capacity, and decrease in tidal volume, shortened inspiratory and expiratory phase duration, and an increase in inspiratory pause duration. These effects were most pronounced during the facial expressions that were difficult to produce. We conclude that changes in heart rate are not the consequence of the capacity of facial activity to recruit emotion-specific autonomic activity but instead are modulated by effort-related changes in respiration.

Adult↗

PubMed1993

Component analysis of task-related respiratory patterns.

The pattern of breathing, determined by time, volumetric and respiratory shape parameters was examined in male students subjected to mental arithmetic tasks, sustained attention tasks, a relaxation task and four levels of graded exercise. Also, the relationships among the respiratory time parameters were determined by performing a factor analysis on a pooled matrix containing the parameter correlations across all experimental conditions. Relative to baseline, the experimental tasks induced rather distinct breathing patterns. During exercise the breathing curves resembled a triangular shape which was caused by a decrease in total breath duration coupled to an increase in both the depth of breathing and the inspiratory duty cycle time. For both the sustained attention and mental arithmetic conditions there was a slight decrease in the depth of breathing and a more pronounced decrease in inspiration time. However, during mental arithmetic the decrease in inspiration was linked to an increase in expiration duration, exhibiting a breathing curve that resembled a 'saw tooth'. In contrast, the attention tasks induced a slight decrease in expiration duration showing a sinusoidal breathing curve which was more similar to the baseline and relaxation breathing pattern. The factor analysis revealed two respiratory factors: a time factor reflecting inspiration, expiration and total cycle duration and a factor related to the inspiratory duty cycle time. We conclude that analysis of breathing patterns with components other than rate and depth of breathing is a potentially useful research tool.

Adolescent↗

PubMed1992

Event-related desynchronization: the effects of energetic and computational demands.

The effects of a subject's activation state on cognitive processing were studied, while subjects performed verbal and non-verbal tasks under a speed and accuracy instruction. It was found that stressing speed influenced the level of prestimulus alpha power and consequently the amount of relative event-related desynchronization (ERD). Increasing task complexity led to an increase in the amount and duration of relative ERD. Both prestimulus level of alpha power and relative ERD were asymmetrically distributed over the left and right hemispheres. No verbal/non-verbal task-dependent asymmetries in phasic ERD were found. The data suggest that the level of prestimulus alpha power is mainly influenced by the subject's activation state, whereas relative ERD mainly reflects phasic changes in cognitive processing.

Adult↗

PubMedDate not supplied

High-Level cognition in phobics: abstract anticipatory memory is associated with the attenuation of physiological reactivity to threat.

The extent to which anxious people benefit from exposure-based treatments seems to depend on the degree to which they activate their fear network during exposure. This study was designed to investigate whether the cognitive processing of threat in anxious individuals is dominated by abstract anticipatory memory, and whether this abstract memory mode is related to the incomplete activation of the fear network. Activation of the fear network was assessed during phobic exposure, as evidenced by the initial autonomic reaction. Spider phobics and controls were presented with a threatening imagery script. Half of them were exposed to a real-life spider. Spider phobics memorized relatively more abstract anticipatory descriptions than concrete sensory descriptions when compared with the control subjects. Only in phobic subjects. higher recognition of abstract anticipatory descriptions was inversely related to heart rate reactivity during exposure. A preferential memory mode for abstract information was related to an attenuated heart rate reactivity to threat in spider phobics. It is suggested that the preferential memory mode for abstract information may inhibit the activation of the subcortical affective memory system, which is crucial for the complete activation of the fear network. The absence of complete fear network activation may play a role in the persistence of anxiety disorders by hindering anxious individuals to learn that the stimuli they fear are not as dangerous as they assumed.

Adult↗