Biomedical subjects

Peter J Lang

Publications and source records attributed to Peter J Lang.

At least 19 recordsLinked to original sources

PubMed2006

Emotional perception: correlation of functional MRI and event-related potentials.

Dense-array electrocortical and functional hemodynamic measures of human brain activity were collected to assess the relationship between 2 established neural measures of emotional reactivity. Recorded in parallel sessions, the slow-wave late positive potential (LPP) and visual cortical blood oxygen level-dependent (BOLD) signals were both modulated by the rated intensity of picture arousal. The amplitude of the LPP correlated significantly with BOLD intensity in lateral occipital, inferotemporal, and parietal visual areas across picture contents. Estimated strength of modeled regional sources did not correlate significantly with regional BOLD intensity. These data suggest that the enhanced positive slow wave seen over posterior sites during emotional picture processing represents activity in a circuit of visual cortical structures, reflecting a perceptual sensitivity to the motivational relevance of visual scenes.

Adult↗

PubMed2006

Fleeting images: rapid affect discrimination in the visual cortex.

Converging electrophysiological and hemodynamic findings indicate sensory processing of emotional pictures is preferred to that of neutral pictures. Whereas neuroimaging studies of emotional picture perception have employed stimulus durations lasting several seconds, recent electrocortical investigations report early visual cortical discrimination between emotionally arousing and neutral picture processing. Here, we use a hybrid picture presentation paradigm covering a range of rapid presentation rates (0.75-6 Hz), while visual system activity is recorded with functional magnetic resonance imaging. Results demonstrate widespread sensitivity to emotional arousal in the secondary and inferior temporal visual cortex. Furthermore, activity in the lateral inferior occipital and medial inferior temporal visual cortex revealed equivalent emotion-sensitive activation across all presentation rates. Results further support the notion that attention and perceptual processing are in part directed by underlying motivational systems.

Adolescent↗

PubMed2006

Emotion, motivation, and the brain: reflex foundations in animal and human research.

This review will focus on a motivational circuit in the brain, centered on the amygdala, that underlies human emotion. This neural circuitry of appetitive/approach and defensive/avoidance was laid down early in our evolutionary history in primitive cortex, sub-cortex, and mid-brain, to mediate behaviors basic to the survival of individuals and the propagation of genes to coming generations. Thus, events associated with appetitive rewards, or that threaten danger or pain, engage attention and prompt information gathering more so than other input. Motive cues also occasion metabolic arousal, anticipatory responses, and mobilize the organism to prepare for action. Findings are presented from research with animals, elucidating these psychophysiological (e.g., cardiovascular, neuro-humoral) and behavioral (e.g., startle potentiation, "freezing") patterns in emotion, and defining their mediating brain circuits. Parallel results are described from experiments with humans, showing similar activation patterns in brain and body in response to emotion cues, co-varying with participants' reports of affective valence and increasing emotional arousal.

Amygdala↗

PubMed2006

The neural basis of narrative imagery: emotion and action.

It has been proposed that narrative emotional imagery activates an associative network of stimulus, semantic, and response (procedural) information. In previous research, predicted response components have been demonstrated through psychophysiological methods in peripheral nervous system. Here we investigate central nervous system concomitants of pleasant, neutral, and unpleasant narrative imagery with functional magnetic resonance imaging. Subjects were presented with brief narrative scripts over headphones, and then imagined themselves engaged in the described events. During script perception, auditory association cortex showed enhanced activation during affectively arousing (pleasant and unpleasant), relative to neutral imagery. Structures involved in language processing (left middle frontal gyrus) and spatial navigation (retrosplenium) were also active during script presentation. At the onset of narrative imagery, supplementary motor area, lateral cerebellum, and left inferior frontal gyrus were initiated, showing enhanced signal change during affectively arousing (pleasant and unpleasant), relative to neutral scripts. These data are consistent with a bioinformational model of emotion that considers response mobilization as the measurable output of narrative imagery.

Acoustic Stimulation↗

PubMed2006

Rapid picture presentation and affective engagement.

Emotional reactions were assessed to pictorial stimuli presented in a continuous stream at rapid speeds that compromise conceptual memory and the processing of specific picture content. Blocks of unpleasant, neutral, or pleasant pictures were presented at the rate of either three pictures per second or seven pictures per second. Even with rapid presentation rates, startle reflexes, corrugator muscle activity, and skin conductance responses were heightened when viewing unpleasant pictures. These effects were stronger later in the aversive block, suggesting that cumulative exposure increasingly activates the defense system. The findings suggest that, despite conceptual masking inherent in rapid serial visual presentation, affective pictures prompt measurable emotional engagement.

Adult↗

PubMed2006

A multi-process account of startle modulation during affective perception.

Modulation of the startle reflex by sensory, attentional, and emotional processes was explored by presenting acoustic startle probes at various delays following picture onset. Within 500 ms of onset, blinks were first greatly facilitated and then inhibited, indicating prepulse facilitation and prepulse inhibition that did not vary with affect. Attention allocation to the picture continued across the viewing interval and was most pronounced for emotional pictures, as determined by attenuation of the P3 component to the startle probe. Startle potentiation for unpleasant pictures occurred later in the viewing interval and was strongest for highly arousing pictures. Taken together, the startle reflex during picture viewing is modulated by sequential and sometimes concurrent processes of prepulse facilitation, prepulse inhibition, attentional inhibition, and affective modulation, with reflex magnitude reflecting the net effect of multiple processes.

Adult↗

PubMed2005

Affective reactions to pictures of ingroup and outgroup members.

A pervasive form of social categorization among humans is between us and them. In this study, we assessed emotional reactions when people viewed pictures depicting members of the same or different ethnic group. African American and European American participants viewed a series of pleasant and unpleasant pictures portraying either ingroup or outgroup members, while physiological, behavioral, and evaluative judgments were measured. Two hypotheses were assessed. The outgroup antipathy hypothesis predicts that people will respond to outgroup pictures with more negative affect than to ingroup pictures. In contrast, the ingroup empathy hypothesis predicts that people will show exaggerated (pleasant and unpleasant) affective responses to pictures of ingroup members, due to group identification or personal relevance. The data provided no support for the antipathy hypothesis, whereas facial EMG, skin conductance, rating, and viewing time data lent support to the ingroup empathy hypothesis, in which greater pleasure and displeasure were apparent when viewing ingroup pictures.

Adolescent↗

PubMed2005

Parallel amygdala and inferotemporal activation reflect emotional intensity and fear relevance.

Much research demonstrates that emotional stimuli prompt increased amygdala and visual cortical activation. Here we measure functional activity in the visual cortex and amygdala with fMRI while selected fearful and control participants view a range of neutral, emotionally arousing, and fear-relevant pictures. BOLD signal in the amygdala and inferotemporal visual cortex closely covaried during emotional picture viewing, increasing systematically with rated picture arousal. Furthermore, fearful individuals reacting to specific fear cues show parallel, heightened activation in these two structures compared with non-fearful controls. The findings suggest an individually-sensitive, positive linear relationship between the arousing quality of visual stimuli and activation in amygdala and ventral visual cortex, supporting the hypothesized functional connectivity described in the animal model.

Adolescent↗

PubMed2005

Parafoveal semantic processing of emotional visual scenes.

The authors investigated whether emotional pictorial stimuli are especially likely to be processed in parafoveal vision. Pairs of emotional and neutral visual scenes were presented parafoveally (2.1 degrees or 2.5 degrees of visual angle from a central fixation point) for 150-3,000 ms, followed by an immediate recognition test (500-ms delay). Results indicated that (a) the first fixation was more likely to be placed onto the emotional than the neutral scene; (b) recognition sensitivity (A') was generally higher for the emotional than for the neutral scene when the scenes were paired, but there were no differences when presented individually; and (c) the superior sensitivity for emotional scenes survived changes in size, color, and spatial orientation, but not in meaning. The data suggest that semantic analysis of emotional scenes can begin in parafoveal vision in advance of foveal fixation.

Adolescent↗

PubMed2005

When good things go bad: the reflex physiology of defense.

For humans, the threat of painful shock greatly potentiates the reflexive startle blink. Moreover, viewing unpleasant, compared with pleasant, pictures also prompts heightened startle reflexes, suggesting that the startle reflex indexes general defensive activation. In this study, pleasant or unpleasant pictures were used to signal shock threat in order to explore how previous affective associations modulate new defensive reactions. When cuing threat of shock, pleasant and unpleasant pictures prompted physiological profiles consistent with defensive activation, indicating that threat of shock renders previously pleasant cues aversive. For unpleasant pictures only, defensive startle was potentiated even when these cues signaled safety. Taken together, the data indicate that (a) regardless of their intrinsic affective meaning, cues signaling shock threat prompt somatic and autonomic reactions consistent with defense, and that (b) intrinsically unpleasant cues continue to prompt defensive activation even when the context of their presentation is specifically non-threatening.

Adult↗

PubMed2004

State anxiety and affective physiology: effects of sustained exposure to affective pictures.

Effects of sustained exposure to emotional stimuli on affective reactions and their recovery were examined to determine whether increasing exposure to a specific emotional content (e.g., unpleasant) cumulatively affects physiological responses; and whether motivational activation persists following sustained exposure. Participants viewed pleasant, neutral, and unpleasant IAPS pictures, presented in blocks separated by an inter-block interval. With increasing exposure to unpleasant pictures, startle magnitude showed greater potentiation, and corrugator EMG activity increased. Both affective startle and corrugator modulation persisted following exposure to unpleasant pictures. The cumulative effects of sustained exposure to unpleasant pictures were enhanced for those reporting higher state anxiety, consistent with the hypothesis that sustained aversive exposure leads to increased defensive activation. These findings suggest sustained exposure to unpleasant pictures may induce a short-term mood state, and may be a useful paradigm to study individuals who vary in symptoms of anxiety.

Affect↗

PubMed2004

Additive effects of emotional content and spatial selective attention on electrocortical facilitation.

Affectively arousing visual stimuli have been suggested to automatically attract attentional resources in order to optimize sensory processing. The present study crosses the factors of spatial selective attention and affective content, and examines the relationship between instructed (spatial) and automatic attention to affective stimuli. In addition to response times and error rate, electroencephalographic data from 129 electrodes were recorded during a covert spatial attention task. This task required silent counting of random-dot targets embedded in a 10 Hz flicker of colored pictures presented to both hemifields. Steady-state visual evoked potentials (ssVEPs) were obtained to determine amplitude and phase of electrocortical responses to pictures. An increase of ssVEP amplitude was observed as an additive function of spatial attention and emotional content. Statistical parametric mapping of this effect indicated occipito-temporal and parietal cortex activation contralateral to the attended visual hemifield in ssVEP amplitude modulation. This difference was most pronounced during selection of the left visual hemifield, at right temporal electrodes. In line with this finding, phase information revealed accelerated processing of aversive arousing, compared to affectively neutral pictures. The data suggest that affective stimulus properties modulate the spatiotemporal process along the ventral stream, encompassing amplitude amplification and timing changes of posterior and temporal cortex.

Adult↗

PubMed2004

Affective picture perception: gender differences in visual cortex?

Activity in extrastriate visual cortex is greater when people view emotional relative to neutral pictures. Prior brain imaging and psychophysiological work has further suggested a bias for men to react more strongly to pleasant pictures, and for women to react more strongly to unpleasant pictures. Here we investigated visual cortical activity using fMRI in 28 men and women during picture viewing. Men and women showed reliably greater visual cortical reactivity during both pleasant and unpleasant pictures, relative to neutral, consistent with the view that the motivational relevance of visual stimuli directs attention and enhances elaborative perceptual processing. However, men did show greater extrastriate activity than women specifically during erotic picture perception, possibly reflecting a gender-specific visual mechanism for sexual selection.

Adolescent↗

PubMed2004

Psychopathy and physiological response to emotionally evocative sounds.

Despite considerable evidence that psychopathic criminals are deviant in their emotional reactions, few studies have examined responses to both pleasurable and aversive stimuli or assessed the role of different facets of psychopathy in affective deviations. This study investigated physiological reactions to emotional sounds in prisoners selected according to scores on the 2 factors of Hare's Psychopathy Checklist--Revised (PCL-R; R. D. Hare, 1991). Offenders high on the PCL-R emotional-interpersonal factor, regardless of scores on the social deviance factor, showed diminished skin conductance responses to both pleasant and unpleasant sounds, suggesting a deficit in the action mobilization component of emotional response. Offenders who scored high only on the social deviance factor showed a delay in heart rate differentiation between affective and neutral sounds. These findings indicate abnormal reactivity to both positive and negative emotional stimuli in psychopathic individuals, and suggest differing roles for the 2 facets of psychopathy in affective processing deviations.

Acoustic Stimulation↗

PubMed2003

Brain activation by disgust-inducing pictures in obsessive-compulsive disorder.

BACKGROUND: There is growing interest in the role of disgust in the pathogenesis of obsessive-compulsive disorder (OCD). METHODS: Eight OCD subjects with contamination preoccupations and eight gender- and age-matched healthy volunteers viewed pictures from the International Affective Picture System during functional magnetic resonance imaging scans. RESULTS: A different distribution of brain activations was found during disgust-inducing visual stimulation in several areas, most notably the insula, compared with neutral stimulation in both OCD subjects and healthy volunteers. Furthermore, whereas activation during the threat-inducing task in OCD subjects showed a pattern similar to that in healthy volunteers, the pattern of activation during the disgust-inducing task was significantly different, including greater increases in the right insula, parahippocampal region, and inferior frontal sites. CONCLUSIONS: This pilot study supports the relevance of disgust in the neurocircuitry of OCD with contamination-preoccupation symptoms; future studies looking at non-OCD individuals with high disgust ratings, non-contamination-preoccupied OCD individuals, and individuals with other anxiety disorders are needed.

Adult↗

PubMed2003

Activation of the visual cortex in motivated attention.

Functional activation (measured with fMRI) in occipital cortex was more extensive when participants view pictures strongly related to primary motive states (i.e., victims of violent death, viewer-directed threat, and erotica). This functional activity was greater than that observed for less intense emotional (i.e., happy families or angry faces) or neutral images (i.e., household objects, neutral faces). Both the extent and strength of functional activity were related to the judged affective arousal of the different picture contents, and the same pattern of functional activation was present whether pictures were presented in color or in grayscale. It is suggested that more extensive visual system activation reflects "motivated attention," in which appetitive or defensive motivational engagement directs attention and facilitates perceptual processing of survival-relevant stimuli.

Adolescent↗

PubMed2003

[Long-term results after perforating corneo-scleroplasty in a case of acute unilateral superior pellucid marginal corneal degeneration].

PURPOSE: This case report shows the long-term results after perforating corneo-scleroplasty in a rare case of superior pellucid marginal corneal degeneration with acute hydrops due to rupture of Descemet's membrane. PATIENT: In the left cornea of a 20-year-old patient with peripheral stromal thinning from 9 to 3 o'clock a rupture in Descemet's membrane occurred followed by lamellar splitting of the mid-stromal region. Due to the decrease in visual acuity and pain from corneal edema a surgical treatment was performed consisting of a perforating/lamellar corneo-scleroplasty protecting the anterior chamber angle. RESULTS: The status has remained stable for 17 years after surgery with nearly clear graft, best corrected visual acuity of 0.8 and no signs of recurrence or progression of the disease. Central astigmatism is regular, the endothelial cell count is 1250/mm2 in the central cornea, the central corneal thickness is 540 microm and only a mild vascularised superficial pannus and slight opacities in the predescemetal layer of the graft are found. There are no anterior synechia. On the right eye visual acuity is 0.8 due to slight amblyopia. There are no corneal changes which would indicate bilaterality of the disease. CONCLUSIONS: Our findings must be interpreted as an atypically localised superior pellucid marginal corneal degeneration with rupture of Descemet's membrane followed by acute corneal hydrops. When reduction of visual acuity or pain occurs a surgical treatment by perforating/lamellar corneo-scleroplasty can be performed stopping the progression of the disease and achieving a stable optical rehabilitation and absence of pain even after decades.

Adult↗

PubMed2003

The psychophysiology of anxiety disorder: fear memory imagery.

Psychophysiological response to fear memory imagery was assessed in specific phobia, social anxiety disorder, panic disorder with agoraphobia, post-traumatic stress disorder (PTSD), and healthy controls. Heart rate, skin conductance, and corrugator muscle were recorded as participants responded to tone cues signaling previously memorized descriptor sentences. Image contents included personal fears, social fears, fears of physical danger, and neutral (low arousal) scenes. Reactions to acoustic startle probes (eyeblink) were assessed during recall imagery and nonsignal periods. Participants were significantly more reactive (in physiology and report of affect) to fear than neutral cues. Panic and PTSD patients were, however, less physiologically responsive than specific phobics and the socially anxious. Panic and PTSD patients also reported the most anxiety and mood symptoms, and were most frequently comorbidly depressed. Overall, physiological reactivity to sentence memory cues was greatest in patients with focal fear of specific objects or events, and reduced in patients characterized by generalized, high negative affect.

Acoustic Stimulation↗