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Stephan F Taylor

Publications and source records attributed to Stephan F Taylor.

24 records · Page 2Linked to original sources
PubMed2003

Valence, gender, and lateralization of functional brain anatomy in emotion: a meta-analysis of findings from neuroimaging.

We performed quantitative meta-analyses on 65 neuroimaging studies of emotion. In an earlier report (NeuroImage 16 (2002), 331). we examined the effects of induction method, specific emotions, and cognitive demand in emotional tasks. This paper focuses on the effects of emotional valence (positive vs negative and approach vs withdrawal) and gender on regional brain activations, with particular emphasis on hypotheses concerning lateralization of brain function in emotion. Overall, we found no support for the hypothesis of overall right-lateralization of emotional function, and limited support for valence-specific lateralization of emotional activity in frontal cortex. In addition, we found that males showed more lateralization of emotional activity, and females showed more brainstem activation in affective paradigms. The study provides evidence that lateralization of emotional activity is more complex and region-specific than predicted by previous theories of emotion and the brain.

Brain↗
PubMed2002

A functional anatomic study of emotion in schizophrenia.

Using salient pictures with aversive (AV) and non-aversive (NA) content, we probed limbic-emotional function in schizophrenia, testing specific hypotheses that the amygdala would exhibit abnormal activity and a relationship with positive symptoms. Fourteen schizophrenic patients and 13 healthy comparison subjects viewed pictures during [15O] water positron emission tomography (PET). Both groups reported identical subjective experience of the aversive stimuli and both activated right insula (AV-NA). The schizophrenic group showed greater activation of the medial prefrontal cortex (MPFC) for the AV-NA comparison. Control subjects activated bilateral amygdaloid and orbitofrontal regions for NA relative to a blank condition (simple visual fixation, BL), whereas schizophrenic subjects only activated left orbitofrontal cortex. Activity in the left amygdala correlated with positive symptoms in the patients. Both groups activated visual cortex, and the schizophrenic subjects exhibited less modulation throughout visual cortex for NA-BL, as well as more focused deficits in the left fusiform and left mid-occipital gyrus for AV-NA, possibly related to decreased eye movements in the schizophrenic patients. Overall, the data are consistent with a general failure to process salient stimuli in schizophrenia, and the findings support the involvement of the amygdala in the positive symptoms of schizophrenia.

Adult↗
PubMed2002

Extended amygdala and emotional salience: a PET activation study of positive and negative affect.

Functional neuroimaging studies have implicated amygdaloid and basal forebrain regions, including sublenticular extended amygdala (SLEA), in the mediation of aversive emotional responses. However, it is not clear whether SLEA responds to 'aversiveness' or to general stimulus salience. We predicted that both pleasant and aversive stimuli would activate this region. Using [(15)O] water PET, we studied 10 healthy subjects while viewing pleasant, aversive, neutral, and blank images. Each subject underwent eight scans, which were processed and averaged with standard statistical methods. Both positive and negative stimuli activated regions in SLEA. Both positive and negative content activated the visual cortex, relative to neutral content. Aversive stimuli deactivated the left frontal pole, relative to positive and neutral stimuli. These findings demonstrate that both positive and negative emotional content evokes processing in the sublenticular/extended amygdala region, suggesting that this region is involved in general emotional processing, such as detection or attribution of salience.

Adolescent↗
PubMed2002

mu-Opioid receptors and limbic responses to aversive emotional stimuli.

Functional neuroimaging studies implicate limbic and paralimbic activity in emotional responses, but few studies have sought to understand neurochemical mechanisms which modulate these responses. We have used positron emission tomography to measure mu-opioid receptor binding, and cerebral blood flow in the same subjects, and demonstrated that the baseline binding potential and the regional cerebral blood flow in the left inferior temporal pole are functionally related. Higher baseline mu-opioid receptor binding potential was associated with lower regional cerebral blood flow in this region during presentation of emotionally salient stimuli. This is consistent with an inhibitory/anxiolytic role of the endogenous opioid system in limbic regions of the temporal lobe and basal forebrain.

Adult↗
PubMed2002

Functional neuroanatomy of emotion: a meta-analysis of emotion activation studies in PET and fMRI.

Neuroimagingstudies with positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have begun to describe the functional neuroanatomy of emotion. Taken separately, specific studies vary in task dimensions and in type(s) of emotion studied and are limited by statistical power and sensitivity. By examining findings across studies, we sought to determine if common or segregated patterns of activations exist across various emotional tasks. We reviewed 55 PET and fMRI activation studies (yielding 761 individual peaks) which investigated emotion in healthy subjects. Peak activation coordinates were transformed into a standard space and plotted onto canonical 3-D brain renderings. We divided the brain into 20 nonoverlapping regions, and characterized each region by its responsiveness across individual emotions (positive, negative, happiness, fear, anger, sadness, disgust), to different induction methods (visual, auditory, recall/imagery), and in emotional tasks with and without cognitive demand. Our review yielded the following summary observations: (1) The medial prefrontal cortex had a general role in emotional processing; (2) fear specifically engaged the amygdala; (3) sadness was associated with activity in the subcallosal cingulate; (4) emotional induction by visual stimuli activated the occipital cortex and the amygdala; (5) induction by emotional recall/imagery recruited the anterior cingulate and insula; (6) emotional tasks with cognitive demand also involved the anterior cingulate and insula. This review provides a critical comparison of findings across individual studies and suggests that separate brain regions are involved in different aspects of emotion.

Brain↗