Psychopathic behavior has long been attributed to a fundamental deficit in fear that arises from impaired amygdala function. Growing evidence demonstrates that fear potentiated startle (FPS) and other psychopathy-related deficits are moderated by focus of attention but, to date, no work on adult psychopathy has examined attentional modulation of the amygdala, or concomitant recruitment of […]
Author Archives: Christine L. Larson
Relations between PET-derived measures of thalamic glucose metabolism and EEG alpha power.
Abstract 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 […]
Asymmetric frontal brain activity, cortisol, and behavior associated with fearful temperament in rhesus monkeys.
Abstract The authors examined the hypothesis that rhesus monkeys with extreme fight frontal electroencephalographic activity would have higher cortisol levels and would be more fearful compared with monkeys with extreme left frontal activity. The authors first showed that individual differences in asymmetric frontal electrical activity are a stable characteristic. Next, the authors demonstrated that relative […]
Metabolic rate in the right amygdala predicts negative affect in depressed patients.
Abstract THE role of the amygdala in major depression was investigated. Resting regional cerebral metabolic rate (rCMRglu) was measured with [18F] fluorodeoxyglucose positron emission tomography (PET) in two samples of subjects using two different PET cameras. The samples consisted of 10 and 17 medication-free depressives and 11 and 13 controls, respectively. Using coregistration of PET […]
EEG alpha power and alpha power asymmetry in sleep and wakefulness.
Abstract 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 […]
Thalamic metabolic rate predicts EEG alpha power in healthy control subjects but not in depressed patients
Abstract Background: 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 hypothesis that the thalamus serves as a neuronal oscillator of alpha rhythms has been supported by studies in animals, but only minimally by studies in humans. Methods: […]
Six-month test-retest reliability of MRI-defined PET measures of regional cerebral glucose metabolic rate in selected subcortical structures
Abstract Test–retest reliability of resting regional cerebral metabolic rate of glucose (rCMR) was examined in selected subcortical structures: the amygdala, hippocampus, thalamus, and anterior caudate nucleus. Findings from previous studies examining reliability of rCMR suggest that rCMR in small subcortical structures may be more variable than in larger cortical regions. We chose to study these […]
Temporal stability of the emotion-modulated startle response.
Abstract 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, […]
Suppression and enhancement of emotional responses to unpleasant pictures.
Abstract 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 […]
Dysfunction in the neural circuitry of emotion regulation- A possible prelude to violence.
Abstract Emotion is normally regulated in the human brain by a complex circuit consisting of the orbital frontal cortex, amygdala, anterior cingulate cortex, and several other interconnected regions. There are both genetic and environmental contributions to the structure and function of this circuitry. We posit that impulsive aggression and violence arise as a consequence of […]