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H C Breiter

Publications and source records attributed to H C Breiter.

At least 19 recordsLinked to original sources
PubMed2005

fMRI of sensitization to angry faces.

This study examined what is communicated by facial expressions of anger and mapped the neural substrates, evaluating the motivational salience of these stimuli. During functional magnetic resonance imaging, angry and neutral faces were presented to human subjects. Across experimental runs, signal adaptation was observed. Whereas fearful faces have reproducibly evoked response habituation in amygdala and prefrontal cortex, angry faces evoked sensitization in the insula, cingulate, thalamus, basal ganglia, and hippocampus. Complementary offline rating and keypress experiments determined an aversive rank ordering of angry, fearful, neutral, and happy faces and revealed behavioral sensitization to the angry faces. Subjects rated angry faces, in contrast to other face categories such as fear, as significantly more likely to directly inflict harm. Furthermore, they rated angry faces as significantly less likely to produce positive emotional outcomes than the other face categories. Together these data argue that angry faces, a directly aversive stimulus, produce a sensitization response.

Adaptation, Psychological↗
PubMed2001

Reward circuitry activation by noxious thermal stimuli.

Using functional magnetic resonance imaging (fMRI), we observed that noxious thermal stimuli (46 degrees C) produce significant signal change in putative reward circuitry as well as in classic pain circuitry. Increases in signal were observed in the sublenticular extended amygdala of the basal forebrain (SLEA) and the ventral tegmentum/periaqueductal gray (VT/PAG), while foci of increased signal and decreased signal were observed in the ventral striatum and nucleus accumbens (NAc). Early and late phases were observed for signals in most brain regions, with early activation in reward related regions such as the SLEA, VT/PAG, and ventral striatum. In contrast, structures associated with somatosensory perception, including SI somatosensory cortex, thalamus, and insula, showed delayed activation. These data support the notion that there may be a shared neural system for evaluation of aversive and rewarding stimuli.

Adult↗
PubMed2001

Beautiful faces have variable reward value: fMRI and behavioral evidence.

The brain circuitry processing rewarding and aversive stimuli is hypothesized to be at the core of motivated behavior. In this study, discrete categories of beautiful faces are shown to have differing reward values and to differentially activate reward circuitry in human subjects. In particular, young heterosexual males rate pictures of beautiful males and females as attractive, but exert effort via a keypress procedure only to view pictures of attractive females. Functional magnetic resonance imaging at 3 T shows that passive viewing of beautiful female faces activates reward circuitry, in particular the nucleus accumbens. An extended set of subcortical and paralimbic reward regions also appear to follow aspects of the keypress rather than the rating procedures, suggesting that reward circuitry function does not include aesthetic assessment.

Adult↗
PubMed2001

Clinical outcomes following cocaine infusion in nontreatment-seeking individuals with cocaine dependence.

BACKGROUND: In this study we explored if laboratory-based cocaine administration to human subjects was associated with long-term adverse outcomes. METHODS: Twenty-one non--reatment seeking individuals with cocaine dependence were evaluated at baseline and again 5 and 10 months following cocaine infusion in a brain imaging study. Outcomes included computer-driven multidimensional clinical assessments and radioimmunoassay of hair. For comparison, identical data were collected from 19 cocaine-dependent subjects who did not receive the infusion. RESULTS: The infused and noninfused groups did not differ on frequency of cocaine use (corroborated by radioimmunoassay of hair), Addiction Severity Index drug composite score, or Hamilton Rating Scale for Depression score at both follow-up time points. In a time-related trend analysis, both groups showed significant reductions in frequency of cocaine use. CONCLUSIONS: Laboratory-based cocaine administration can be a safe paradigm even in individuals who are not engaged in treatment.

Aged↗
PubMed2001

Functional imaging of neural responses to expectancy and experience of monetary gains and losses.

Neural responses accompanying anticipation and experience of monetary gains and losses were monitored by functional magnetic resonance imaging. Trials comprised an initial "prospect" (expectancy) phase, when a set of three monetary amounts was displayed, and a subsequent "outcome" phase, when one of these amounts was awarded. Hemodynamic responses in the sublenticular extended amygdala (SLEA) and orbital gyrus tracked the expected values of the prospects, and responses to the highest value set of outcomes increased monotonically with monetary value in the nucleus accumbens, SLEA, and hypothalamus. Responses to prospects and outcomes were generally, but not always, seen in the same regions. The overlap of the observed activations with those seen previously in response to tactile stimuli, gustatory stimuli, and euphoria-inducing drugs is consistent with a contribution of common circuitry to the processing of diverse rewards.

Adult↗
PubMed2000

The validity of self-reported drug use in non-treatment seeking individuals with cocaine dependence: correlation with biochemical assays.

Accurate estimate of drug exposure plays an important role in studies of the neurobiology of drug dependence. The validity of self-reported drug use by subjects participating in such studies has not been well established. This study examined the relationship between self-reported drug use and biological markers in 18 non-treatment-seeking cocaine-dependent individuals participating in research on the effects of cocaine on the brain. A significant relationship was found between self-reported frequency of cocaine use and hair cocaine concentration. Frequency of alcohol use correlated significantly with plasma carbohydrate-deficient transferrin and aspartate aminotransferase levels. These results suggest that self-reported substance use in non-treatment seeking research subjects is generally valid.

Adult↗
PubMed1999

Depressive symptomatology and cocaine-induced pituitary-adrenal axis activation in individuals with cocaine dependence.

The hypothalamic-pituitary-adrenal (HPA) axis plays a role in cocaine dependence and major depressive disorder. The authors examined the correlation between baseline depressive symptomatology and pituitary-adrenal axis activation induced by acute cocaine challenge. Twelve patients with cocaine dependence were administered an iv bolus of cocaine (0.6 mg/kg) and their plasma was assayed for levels of adrenocorticotropic hormone (ACTH) and cortisol. Depressive symptomatology was assessed with total Hamilton rating scale for depression (HRSD) scores and its vegetative and cognitive superfactors. Cocaine produced a mean increase from baseline of 261% for ACTH and 73% for cortisol plasma levels. Changes in ACTH (r=0.69) and cortisol (r=0.59) were positively and significantly correlated with total HRSD scores and its vegetative, but not cognitive, factor symptom cluster. These results suggest that the HPA axis may be involved in affective disturbances associated with the use of cocaine. Implications of these data for the pathophysiology of cocaine dependence are discussed.

Adrenocorticotropic Hormone↗
PubMed1999

Functional magnetic resonance imaging of brain reward circuitry in the human.

To produce behavior, motivational states necessitate at least three fundamental operations, including (1) selection of objectives focused on goal-objects, (2) compilation of goal-object information, and (3) determination of physical plans for securing goal-objects. The second of these general operations has been theorized to involve three subprocesses: (a) feature detection and other perceptual processing of putative goal-object "rewards," (b) valuation of goal-object worth in the context of potential hedonic deficit states, and (c) extraction of incidence and temporal data regarding the goal-object. A number of subcortical brain regions appear to be involved in these three informational subprocesses, in particular, the amygdala, sublenticular extended amygdala (SLEA) of the basal forebrain, and nucleus accumbens/subcallosal cortex (NAc/SCC). Components of the amygdala, SLEA, and NAc/SCC together constitute the larger anatomic structure of the extended amygdala. Functional magnetic resonance imaging (fMRI) studies of humans have recently begun to localize these subcortical regions within the extended amygdala during specific experimental conditions. In this manuscript, two human cocaine- infusion studies and one cognitive psychology experiment are reviewed in relation to their pattern of fMRI activation within regions of the extended amygdala. Activation in the NAc/SCC, in particular, is evaluated in relation to a hypothesis that one function of the NAc/SCC and associated brain regions is the evaluation of goal-object incidence data for the computation of conditional probabilities regarding goal-object availability. Further work is warranted to test hypothesized functions for all regions within the extended amygdala and integrate them toward an understanding of motivated behavior.

Animals↗
PubMed1999

Human brain activation under controlled thermal stimulation and habituation to noxious heat: an fMRI study.

Brain activity was studied with functional magnetic resonance imaging (fMRI) following thermal stimulation. Two groups (n = 6/group) of human male volunteers were given up to four noxious (46 degrees C) and four non-noxious (41 degrees C) stimuli. In the 46 degrees C experiment, positive signal changes were found in the frontal gyri, anterior and posterior cingulate gyrus, thalamus, motor cortex, somatosensory cortex (SI and SII), supplementary motor area, insula, and cerebellum. Low-level negative signal changes appeared in the amygdala and hypothalamus. All regions activated by 46 degrees C were also activated by 41 degrees C. However, except for SI and thalamus, significantly more activation was observed for the 46 degrees C stimulus. A significant attenuation of the signal change was observed by the third stimulus for the 46 degrees C, but not for 41 degrees C experiment. Similar findings were replicated in the second group. These fMRI findings specify differences between somatosensory and pain sensation and suggest a number of rich avenues for future research.

Adult↗
PubMed1998

A functional magnetic resonance imaging study of auditory vigilance with low and high information processing demands.

This study identified the brain activations associated with auditory vigilance tasks, using functional magnetic resonance imaging. We created auditory continuous performance tests (CPTs) in which a demanding task (working memory task) was made more difficult than a simple vigilance task by increasing working memory and interference filtering demands. Two cohorts of normal male controls performed significantly worse on the working memory CPT than on the vigilance task. Compared to the vigilance task, performance of the working memory task produced significant signal change in lateral and medial prefrontal cortex, precentral cortex, temporal lobe, including insula and hippocampus, parietal-occipital cortex, cingulate, thalamus, and superior colliculus. Performance and degree of activation was associated with an estimate of IQ. Further research should clarify the contributions of working memory and interference filtering to the activated network.

Adult↗
PubMed1998

Cocaine decreases cortical cerebral blood flow but does not obscure regional activation in functional magnetic resonance imaging in human subjects.

The authors used functional magnetic resonance imaging (fMRI) to determine whether acute intravenous (i.v.) cocaine use would change global cerebral blood flow (CBF) or visual stimulation-induced functional activation. They used flow-sensitive alternating inversion recovery (FAIR) scan sequences to measure CBF and blood oxygen level-dependent (BOLD) sensitive T2* scan sequences during visual stimulation to measure neuronal activation before and after cocaine and saline infusions. Cocaine (0.6 mg/kg i.v. over 30 seconds) increased heart rate and mean blood pressure and decreased end tidal carbon dioxide (CO2). All measures returned to baseline by 2 hours, the interinfusion interval, and were unchanged by saline. Flow-sensitive alternating inversion recovery imaging demonstrated that cortical gray matter CBF was unchanged after saline infusion (-2.4 +/- 6.5%) but decreased (-14.1 +/- 8.5%) after cocaine infusion (n = 8, P < 0.01). No decreases were detected in white matter, nor were changes found comparing BOLD signal intensity in cortical gray matter immediately before cocaine infusion with that measured 10 minutes after infusion. Visual stimulation resulted in comparable BOLD signal increases in visual cortex in all conditions (before and after cocaine and saline infusion). Despite a small (14%) but significant decrease in global cortical gray matter CBF after acute cocaine infusion, specific regional increases in BOLD imaging, mediated by neurons, can be measured reliably.

Adult↗
PubMed1997

Reduced basal ganglia volumes in trichotillomania measured via morphometric magnetic resonance imaging.

A morphometric magnetic resonance imaging (MRI) study compared volumes of brain structures in 10 female subjects with trichotillomania (repetitive hair-pulling) versus 10 normal controls matched for sex, age, handedness, and education. Three-dimensional MRI scans were blindly normalized and segmented using well-characterized semiautomated intensity and differential contour algorithms by signal intensity-frequency histograms. Consistent with one a priori hypothesis, left putamen volume was found to be significantly smaller in trichotillomania subjects as compared with normal matched controls. This is the first report of a structural brain abnormality in trichotillomania. Results are discussed in terms of putative relationships between trichotillomania, Tourette's syndrome, and obsessive-compulsive disorder.

Adult↗
PubMed1997

Acute effects of cocaine on human brain activity and emotion.

We investigated brain circuitry mediating cocaine-induced euphoria and craving using functional MRI (fMRI). During double-blind cocaine (0.6 mg/kg) and saline infusions in cocaine-dependent subjects, the entire brain was imaged for 5 min before and 13 min after infusion while subjects rated scales for rush, high, low, and craving. Cocaine induced focal signal increases in nucleus accumbens/subcallosal cortex (NAc/SCC), caudate, putamen, basal forebrain, thalamus, insula, hippocampus, parahippocampal gyrus, cingulate, lateral prefrontal and temporal cortices, parietal cortex, striate/extrastriate cortices, ventral tegmentum, and pons and produced signal decreases in amygdala, temporal pole, and medial frontal cortex. Saline produced few positive or negative activations, which were localized to lateral prefrontal cortex and temporo-occipital cortex. Subjects who underwent repeat studies showed good replication of the regional fMRI activation pattern following cocaine and saline infusions, with activations on saline retest that might reflect expectancy. Brain regions that exhibited early and short duration signal maxima showed a higher correlation with rush ratings. These included the ventral tegmentum, pons, basal forebrain, caudate, cingulate, and most regions of lateral prefrontal cortex. In contrast, regions that demonstrated early but sustained signal maxima were more correlated with craving than with rush ratings; such regions included the NAc/SCC, right parahippocampal gyrus, and some regions of lateral prefrontal cortex. Sustained negative signal change was noted in the amygdala, which correlated with craving ratings. Our data demonstrate the ability of fMRI to map dynamic patterns of brain activation following cocaine infusion in cocaine-dependent subjects and provide evidence of dynamically changing brain networks associated with cocaine-induced euphoria and cocaine-induced craving.

Adult↗
PubMed1997

Striatal recruitment during an implicit sequence learning task as measured by functional magnetic resonance imaging.

Prior research has repeatedly implicated the striatum in implicit sequence learning; however, imaging findings have been inconclusive with respect to the sub-territories and laterality involved. Using functional magnetic resonance imaging (fMRI), we studied brain activation profiles associated with performance of the serial reaction time task (SRT) in 10 normal right-handed males. Behavioral results indicate that significant implicit learning occurred, uncontaminated by significant explicit knowledge. Concatenated fMRI data from the entire cohort revealed significant right-lateralized activation in both the caudate and putamen. Analysis of fMRI data from individual subjects showed inter-individual variability as to the precise territories involved, including right as well as left caudate and putamen. Interestingly, all seven subjects who manifested robust learning effects exhibited significant activation within the putamen. Moreover, among those seven subjects, the magnitude of signal intensity change within the putamen correlated significantly with the magnitude of reaction time advantage achieved. These findings demonstrate right-sided striatal activation across subjects during implicit sequence learning, but also highlight interindividual variability with respect to the laterality and striatal subterritories involved. In particular, results from individual subjects suggest that, during the SRT, the reaction time advantage garnered via implicit sequence learning might be predominantly associated with activity within the putamen.

Adult↗
PubMed1996

Functional magnetic resonance imaging of symptom provocation in obsessive-compulsive disorder.

BACKGROUND: The new technique of functional magnetic resonance imaging was used to investigate the mediating neuroanatomy of obsessive-compulsive disorder symptoms. METHODS: Ten patients with obsessive-compulsive disorder and 5 normal subjects were studied via functional magnetic resonance imaging during control and provoked conditions. Data analysis entailed parametric and nonparametric statistical mapping. RESULTS: Statistical maps (nonparametric; P < 10(-3)) showed activation for 70% or more of patients with obsessive-compulsive disorder in medial orbitofrontal, lateral frontal, anterior temporal, anterior cingulate, and insular cortex, as well as caudate, lenticulate, and amygdala. No normal subjects exhibited activation in any brain region. CONCLUSIONS: Results of functional magnetic resonance imaging were consistent with past studies of obsessive-compulsive disorder that used other functional neuroimaging modalities. However, paralimbic and limbic activations were more prominent in the present study.

Adult↗
PubMed1996

Cerebral structural abnormalities in obsessive-compulsive disorder. A quantitative morphometric magnetic resonance imaging study.

BACKGROUND: A previous pilot study of only posterior brain regions found lower white-matter volume in patients with obsessive-compulsive disorder than in normal control subjects. We used new cohorts of patients and matched normal control subjects to study whole-brain volume differences between these groups with magnetic resonance imaging-based morphometry. METHODS: Ten female patients with obsessive-compulsive disorder and 10 female control subjects, matched for handedness, age, weight, education, and verbal IQ, underwent magnetic resonance imaging with a 3-dimensional volumetric protocol. Scans were blindly normalized and segmented by means of well-characterized semiautomated intensity contour mapping and differential intensity contour algorithms. Brain structures investigated included the cerebral hemispheres, cerebral cortex, diencephalon, caudate, putamen, globus pallidus, hippocampus amygdala, third and fourth ventricles, corpus callosum, operculum, cerebellum, and brain stem. Anterior to posterior neocortical regions, including precallosum, anterior pericallosum, posterior pericallosum, and retrocallosum, with adjacent white matter were also measured. Volumes found different between groups were correlated with Yale-Brown Obsessive Compulsive Scale score and Rey-Osterieth Complex Figure Test measures. RESULTS: Confirming results of our earlier pilot study and expanding the findings to the whole brain, patients with obsessive-compulsive disorder had significantly less total white matter but, in addition, significantly greater total cortex and opercular volumes. Severity of obsessive-compulsive disorder and nonverbal immediate memory correlated with opercular volume. CONCLUSIONS: Replication of volumetric white-matter differences suggests a widely distributed structural brain abnormality in obsessive-compulsive disorder. Whereas determining the etiogenesis may require research at a microscopic level, understanding its functional significance can be further explored via functional neuroimaging and neuropsychological studies.

Adult↗
PubMed1996

Functional MRI and the study of OCD: from symptom provocation to cognitive-behavioral probes of cortico-striatal systems and the amygdala.

Functional magnetic resonance imaging (fMRI) first appeared in 1991. Since that time there has been a burgeoning use of the technology by psychiatric researchers and neuroscientists. Our group first used fMRI to study obessive compulsive disorder (OCD) with a symptom provocation paradigm and then moved to the use of circuitry-specific cognitive-behavioral probes. The techniques we utilized for the symptom provocation study remain valid today, but have been supplemented by a wide array of new tools. Functional MRI continues to be a rapidly developing technology which could become the gold standard for neuroimaging research in psychiatry. With this in mind, this paper focuses on the past, present, and future applications of fMRI to one model illness, namely OCD. We examine the strengths and limitations of our initial OCD symptom provocation study and then evaluate the use of fMRI with cognitive-behavioral probes of cortico-striatal circuitry and limbic (amygdala) circuitry. We conclude with a brief summary of foreseeable developments which will influence the implementation of fMRI for psychiatric neuroscience in general.

Arousal↗