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Despite the prominence of emotional dysfunction in psychopathology, relatively few experiments have explicitly studied emotion regulation in adults. The present study examined one type of emotion regulation: voluntary regulation of short-term emotional responses to unpleasant visual stimuli. In a sample of 48 college students, both eyeblink startle magnitude and corrugator activity were sensitive to experimental manipulation. Instructions to suppress negative emotion led to both smaller startle eyeblinks and decreased corrugator activity. Instructions to enhance negative emotion led to larger startle eyeblinks and increased corrugator activity. Several advantages of this experimental manipulation are discussed, including the use of both a suppress and an enhance emotion condition, independent measurement of initial emotion elicitation and subsequent regulation of that emotion, the use of a completely within-subjects design, and the use of naturalistic emotion regulation strategies.

Electroencephalogram (EEG) alpha power has been demonstrated to be inversely related to mental activity and has subsequently been used as an indirect measure of brain activation. The thalamus has been proposed as an important site for modulation of rhythmic alpha activity. Studies in animals have suggested that cortical alpha rhythms are correlated with alpha rhythms in the thalamus. However, little empirical evidence exists for this relation in humans. In the current study, resting EEG and a fluorodeoxyglucose positron emission tomography scan were measured during the same experimental session. Over a 30-min period, average EEG alpha power across 28 electrodes from 27 participants was robustly inversely correlated with glucose metabolic activity in the thalamus. These data provide the first evidence for a relation between alpha EEG power and thalamic activity in humans.

The present study was undertaken to determine whether aversiveness contributes to startle potentiation in anticipation of affective pictures above and beyond the effects of emotional arousal. Further, participants high in trait anxious apprehension, which is characterized by worry about the future, were expected to show especially pronounced anticipatory startle responses. Startle blink reflex was measured during warning stimuli that predicted the valence of ensuing aversive/unpleasant, pleasant, or neutral pictures. Startle magnitude was larger in anticipation of aversive than of pleasant pictures and smallest in anticipation of neutral pictures. Enhanced startle potentiation was not found in anxious apprehension subjects. These data suggest that the aversive nature of stimuli contribute to the potentiation of startle above and beyond the effects of emotional arousal, which may be a universal phenomenon not modulated by individual differences.

In the present study, we examined the stability of one measure of emotion, the emotion-modulated acoustic startle response, in an undergraduate sample. Using the acoustic startle paradigm on two different occasions, we measured stability of affective modulation of the startle response during and following the presentation of pictures selected to be of positive, negative, or neutral emotional valence. The two assessments were separated by 4 weeks. Two groups of subjects were compared: one group that viewed the same pictures at each assessment and a second group that viewed different pictures at the second assessment. We found that viewing different pictures at two assessments separated by 4 weeks yielded moderate stability of the emotion modulation of startle magnitude, whereas subjects who viewed the same pictures at both assessments showed poor stability. Furthermore, this difference was due to the stability of responses to high versus low arousal pictures, not to differences in valence.

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The ratio of fronto-central theta (4-7 Hz) to beta oscillations (13-30 Hz), known as the theta-beta ratio, is negatively correlated with attentional control, reinforcement learning, executive function, and age. Although theta-beta ratios have been found to decrease with age in adolescents and young adults, theta has been found to increase with age in older adults.Moreover, age-related decreases in individual alpha peak frequency and flattening of the 1/f aperiodic component may artifactually inflate the association between theta-beta ratio and age. These factors lead to an incomplete understanding of how theta-beta ratio varies across the lifespan and the extent to which variation is due to a conflation of aperiodic and periodic activity. We conducted a partially preregistered analysis examining the cross-sectional associations between age and resting canonical fronto-central theta-beta ratio, individual alpha peak frequency, and aperiodic component (n = 268; age 36-84, M = 55.8, SD = 11.0).Age was negatively associated with theta-beta ratios, individual peak alpha frequencies, and the aperiodic exponent. The correlation between theta-beta ratios and age remained after controlling for individual peak alpha frequencies, but was non-significant when controlling for the aperiodic exponent. Aperiodic exponent fully mediated the relationship between thetabeta ratio and age, although beta remained significantly associated with age after controlling for theta, individual peak alpha, and aperiodic exponent. Results replicate previous observations and show age-related decreases in theta-beta ratios are not due to age-related decreases in individual peak alpha frequencies but primarily explained by flattening of the aperiodic component with age.

Asymmetry of waking electroencephalography (EEG) alpha power in frontal regions has been correlated with waking emotional reactivity and the emotional content of dream reports. Little is known regarding alpha asymmetry during sleep. The present study was performed to compare alpha power and alpha power asymmetry in various brain regions across states of sleep and wakefulness. Waking and sleep EEG were recorded in a group of patients undergoing polysomnographic evaluation for possible sleep disorders. Alpha EEG asymmetry in frontal and temporal regions was significantly correlated in waking versus sleep, particularly during rapid eye movement (REM) sleep. These results suggest that patterns of frontal alpha asymmetry are stable across sleep and waking and may be related to emotional reactivity during dreaming. During sleep, alpha power was highest during slow-wave sleep and lowest during REM sleep. Implications of these data for understanding the functional significance of alpha power during waking and sleeping are considered.