Biomedical subjects

Thomas W Uhde

Publications and source records attributed to Thomas W Uhde.

4 recordsLinked to original sources

PubMed2005

Neural substrates for voluntary suppression of negative affect: a functional magnetic resonance imaging study.

BACKGROUND: Successful control of affect partly depends on the capacity to modulate negative emotional responses through the use of cognitive strategies. Although the capacity to regulate emotions is critical to mental well-being, its neural substrates remain unclear. METHODS: We used functional magnetic resonance imaging to ascertain brain regions involved in the voluntary regulation of emotion and whether dynamic changes in negative emotional experience can modulate their activation. Fourteen healthy subjects were scanned while they either maintained the negative affect evoked by highly arousing and aversive pictures (e.g., experience naturally) or suppressed their affect using cognitive reappraisal. In addition to a condition-based analysis, online subjective ratings of intensity of negative affect were used as covariates of brain activity. RESULTS: Inhibition of negative affect was associated with activation of dorsal anterior cingulate, dorsal medial prefrontal, and lateral prefrontal cortices, and attenuation of brain activity within limbic regions (e.g., nucleus accumbens/extended amygdala). Furthermore, activity within dorsal anterior cingulate was inversely related to intensity of negative affect, whereas activation of the amygdala was positively covaried with increasing negative affect. CONCLUSIONS: These findings highlight a functional dissociation of corticolimbic brain responses, involving enhanced activation of prefrontal cortex and attenuation of limbic areas, during volitional suppression of negative emotion.

Adult↗

PubMed2005

Twenty-four hour growth hormone secretion in patients with panic disorder.

BACKGROUND: Patients with panic disorder have blunted growth hormone (GH) responses to clonidine, suggesting subsensitivity of post-synaptic alpha(2)-adrenoreceptors, presumably in response to excessive central noradrenergic outflow. However, basal levels of GH release over a full circadian cycle have not been examined in panic. Reduced basal GH release would suggest an overall hypo-active GH system rather than a specific alpha-adrenergic abnormality. METHODS: To determine whether panic patients show reduced basal GH secretion, 20 patients and 12 healthy controls were studied. Blood samples were drawn every 15 min for 24 h and plasma was assayed for GH. Patients were restudied during successful treatment with alprazolam. Groups were compared on overnight and daytime GH secretion and circadian patterns of release. RESULTS: Patients showed normal levels on all measures of GH release. Treatment may have reduced nocturnal GH release slightly, but treated patients still did not differ from controls. The normal predominance of sleep over waking GH secretion was seen in both groups. CONCLUSIONS: Panic patients, in contrast to depressed patients, have normal somatotrophic axis activity when measured in a resting state over a full circadian cycle. GH dysregulation may only be evident in these patients in activation paradigms and has been most consistently demonstrated by challenges with the alpha(2)-noradrenergic agonist, clonidine.

Adult↗

PubMed2003

Sleep panic attacks: a micro-movement analysis.

Earlier work by our group and others has pointed to a role for movement during sleep in sleep-panic attacks. Specifically, our group has reported that panic disorder patients, as a group, appear to move more during sleep than age-matched controls, whereas the subgroup of panic disorder who "panic" during sleep move less on the nights they experience sleep-panic attacks than they do on nights without sleep-panic attacks. We studied the movement of sleep-panic patients in a more detailed fashion with more than one sleep movement index. Fourteen patients with sleep-panic attacks were compared with 14 waking panic patients, 13 social phobic patients, and 14 normal controls. Subjects from the other groups were age matched to the sleep-panic group. Their comparison study night corresponded to the night number of the sleep-panic attack. Sleep-panic patients did move less on panic nights than did the normal controls on the corresponding sleep-panic night according to two separate sleep movement indices. Although not statistically significant, sleep-panic patients also moved less on their panic night than did either of the other anxious groups on corresponding nights. Rechtshaffen and Kales' Movement Time (MT) measure appears to overestimate actual min of movement during sleep in all subjects. The movement noted in sleep-panic patients may have some role in the pathophysiology of sleep-panic attacks. A possible mechanism is explained.

Adult↗

PubMed2003

Skin picking and sleep disturbances: relationship to anxiety and need for research.

Pathological excoriation (PE) or skin picking is seen in nearly 2% of patients attending dermatology clinics and is often associated with anxiety, stress and frequent help-seeking behaviors. While anxiety and stress are thought to cause poor sleep in the general population, not all anxious people, even those with disabling anxiety disorders, necessarily suffer from insomnia or other sleep problems. The relationship between anxiety symptoms and poor sleep, therefore, remains unclear and sleep quality in PE is unknown. We examined the sleep quality and levels of anxiety in dermatological patients with PE. Dermatological patients with (n = 10) and without (n = 10) PE and healthy controls (n = 10) were assessed on standardized and validated measures of subjective sleep quality [Pittsburgh Sleep Quality Index (PSQI)], anxiety (Spielberger State and Trait Anxiety Inventory; modified Zung Anxiety Scale), stress (Perceived Stress Scale) and work and social disability [Sheehan Disability Inventory subscale (SDI-4)]. Patients with dermatological complaints as a group reported poorer sleep quality, higher scores on Spielberger State and Zung anxiety, perceived stress, and SDI-4. Among both groups of dermatological patients, only the PE group had significantly poor sleep, high anxiety, and perceived stress compared to healthy controls. In the dermatological patients with PE, PSQI-global scores were significantly positively correlated to Spielberger State and Zung Anxiety scores. Dermatological patients with PE are more anxious and have poorer subjective sleep compared to dermatological patients without PE and healthy. Future research is needed to elucidate these relationship factors and to develop new behavioral and drug treatments for the management of PE.

Adult↗