Showing papers by "Raymond J. Dolan published in 2001"
TL;DR: The authors used event-related fMRI to assess whether brain responses to fearful versus neutral faces are modulated by spatial attention, and found that right fusiform activity was greater for fearful than neutral faces, independently of the attention effect on this region.
1,719 citations
TL;DR: Brain activity during delay between reward-related decisions and their outcomes is measured to highlight distinct contributions of cognitive uncertainty and autonomic arousal to anticipatory neural activity in prefrontal cortex.
660 citations
TL;DR: In this paper, the authors reported differential amygdala responses in G.Y. to presentation of fearful and fear-conditioned faces in his blind hemifield, which indicated that an extrageniculostriate (colliculo-thalamo-amygdala) neural pathway can process fearrelated stimuli independently of both the striate cortex and normal phenomenal visual awareness.
Abstract: Patient G.Y. is able to discriminate emotional facial expressions presented in his blind (right) hemifield despite an extensive lesion of the corresponding (left) striate cortex. One proposal is that this residual ability (affective "blindsight") depends on a subcortical visual pathway comprising the superior colliculus, posterior (extrageniculate) thalamus and amygdala. Here we report differential amygdala responses in G.Y. to presentation of fearful and fear-conditioned faces in his blind (right) hemifield. These amygdala responses exhibited condition-dependent covariation with neural activity in the posterior thalamus and superior colliculus. Our results provide further evidence that an extrageniculostriate (colliculo-thalamo-amygdala) neural pathway can process fear-related stimuli independently of both the striate cortex and normal phenomenal visual awareness
565 citations
TL;DR: It is shown that the perceived attractiveness of an unfamiliar face increases brain activity in the ventral striatum of the viewer when meeting the person's eye, and decreases activity when eye gaze is directed away, indicating that central reward systems may be engaged during the initiation of social interactions.
Abstract: Faces are visual objects in our environment that provide strong social cues, with the eyes assuming particular importance. Here we show that the perceived attractiveness of an unfamiliar face increases brain activity in the ventral striatum of the viewer when meeting the person's eye, and decreases activity when eye gaze is directed away. Depending on the direction of gaze, attractiveness can thus activate dopaminergic regions that are strongly linked to reward prediction, indicating that central reward systems may be engaged during the initiation of social interactions.
448 citations
TL;DR: It is suggested that whereas there are modality-specific pathways for processing the juxtaposition of mental sets necessary for the appreciation of jokes, a common component of humor is expressed in activity in medial ventral prefrontal cortex, a region involved in reward processing.
Abstract: Humor, a unique human characteristic, is critical in thought, communication and social interaction Successful jokes involve a cognitive juxtaposition of mental sets, followed by an affective feeling of amusement; we isolated these two components of humor by using event-related fMRI on subjects who listened to auditorily presented semantic and phonological jokes (puns) and indicated whether or not they found the items amusing Our findings suggest that whereas there are modality-specific pathways for processing the juxtaposition of mental sets necessary for the appreciation of jokes, a common component of humor is expressed in activity in medial ventral prefrontal cortex, a region involved in reward processing
336 citations
TL;DR: This investigation of how gaze direction influences face processing in an fMRI study, where seen gaze and head direction could independently be direct or deviated, found direct gaze led to greater correlation between activity in the fusiform and the amygdala.
334 citations
TL;DR: Findings suggest that neural activity mediating episodic retrieval of contextual information and its subsequent processing is modulated by emotion in at least two ways: first, there is enhancement of activity in networks supporting episodic retrieved neutral information, and second, regions known to be activated when emotional information is encountered in the environment are also active when emotionalInformation is retrieved from memory.
299 citations
TL;DR: These findings provide empirical support for a theory proposing a hierarchical representation of bodily states and an absence of afferent feedback concerning autonomically generated bodily states was associated with subtle impairments of emotional responses in PAF patients.
Abstract: Changes in bodily states, particularly those mediated by the autonomic nervous system, are crucial to ongoing emotional experience A theoretical model proposes a first-order autoregulatory representation of bodily state at the level of dorsal pons, and a second-order experience-dependent re-mapping of changes in bodily state within structures such as cingulate and medial parietal cortices We tested these anatomical predictions using positron emission tomography and a human neurological model (pure autonomic failure), in which peripheral autonomic denervation prevents the emergence of autonomic responses Compared to controls, we observed task-independent differences in activity of dorsal pons and context-induced differences in cingulate and medial parietal activity in PAF patients An absence of afferent feedback concerning autonomically generated bodily states was associated with subtle impairments of emotional responses in PAF patients Our findings provide empirical support for a theory proposing a hierarchical representation of bodily states
291 citations
TL;DR: The data suggest that the amygdala is important for emotional crossmodal sensory convergence with the associated perceptual bias during fear processing, being mediated by task-related modulation of face-processing regions of fusiform cortex.
Abstract: In social environments, multiple sensory channels are simultaneously engaged in the service of communication. In this experiment, we were concerned with defining the neuronal mechanisms for a perceptual bias in processing simultaneously presented emotional voices and faces. Specifically, we were interested in how bimodal presentation of a fearful voice facilitates recognition of fearful facial expression. By using event-related functional MRI, that crossed sensory modality (visual or auditory) with emotional expression (fearful or happy), we show that perceptual facilitation during face fear processing is expressed through modulation of neuronal responses in the amygdala and the fusiform cortex. These data suggest that the amygdala is important for emotional crossmodal sensory convergence with the associated perceptual bias during fear processing, being mediated by task-related modulation of face-processing regions of fusiform cortex.
263 citations
TL;DR: Regression analysis of the neuroimaging data revealed that left amygdala and right lateral orbitofrontal rCBF covaried as a function of stimulus category (i.e., food vs non-food).
Abstract: We used positron emission tomography to measure regional cerebral blood flow (rCBF) in 10 healthy volunteers performing a recognition memory task with food and non-food items. The biological salience of the food stimuli was manipulated by requiring subjects to fast before the experiment and eat to satiation at fixed time points during scanning. All subjects showed enhanced recognition of food stimuli (relative to non-food) in the fasting state. Satiation significantly reduced the memory advantage for food. Left amygdala rCBF covaried positively with recognition memory for food items, whereas rCBF in right anterior orbitofrontal cortex covaried with overall memory performance. Right posterior orbitofrontal rCBF covaried positively with hunger ratings during presentation of food items. Regression analysis of the neuroimaging data revealed that left amygdala and right lateral orbitofrontal rCBF covaried as a function of stimulus category (i.e., food vs non-food). These results indicate the involvement of amygdala and discrete regions of orbitofrontal cortex in the integration of perceptual (food), motivational (hunger), and cognitive (memory) processes in the human brain.
223 citations
TL;DR: The results indicate that learning an association between biologically salient stimuli of different sensory modalities involves parallel changes of neural activity in segregated amygdala subregions and unimodal sensory cortices.
TL;DR: In this article, the authors used PET to investigate cerebral activity relating to the cognitively driven modulation of sympathetic activity and found that relaxation was associated with significant increases in left anterior cingulate and globus pallidus activity.
Abstract: The mechanisms by which cognitive processes influence states of bodily arousal are important for understanding the pathogenesis and maintenance of stress-related morbidity. We used PET to investigate cerebral activity relating to the cognitively driven modulation of sympathetic activity. Subjects were trained to perform a biofeedback relaxation exercise that reflected electrodermal activity and were subsequently scanned performing repetitions of four tasks: biofeedback relaxation, relaxation without biofeedback and two corresponding control conditions in which the subjects were instructed not to relax. Relaxation was associated with significant increases in left anterior cingulate and globus pallidus activity, whereas no significant increases in activity were associated with biofeedback compared with random feedback. The interaction between biofeedback and relaxation, highlighting activity unique to biofeedback relaxation, was associated with enhanced anterior cingulate and cerebellar vermal activity. These data implicate the anterior cingulate cortex in the intentional modulation of bodily arousal and suggest a functional neuroanatomy of how cognitive states are integrated with bodily responses. The findings have potential implications for a mechanistic account of how therapeutic interventions, such as relaxation training in stress-related disorders, mediate their effects.
TL;DR: It is concluded that arguments involving relations that can be easily mapped onto explicit spatial relations engage a visuo-spatial system, irrespective of concrete or abstract content.
TL;DR: A hypothesis that cerebral representation of anticipatory arousal biases behavior and guides decision-making is led to a hypothesis that healthy subjects show a preference for low-risk arousal.
TL;DR: The finding that fronto-polar cortex mediates rule learning supports a functional contribution of this region to generic reasoning and problem-solving behaviours.
Abstract: Despite a need for rule learning in everyday life, the brain regions involved in explicit rule induction remain undetermined. Here we use event-related functional magnetic resonance imaging to measure learning-dependent neuronal responses during an explicit categorization task. Subjects made category decisions, with feedback, to exemplar letter strings for which the rule governing category membership was periodically changed. Bilateral fronto-polar prefrontal cortices were selectively engaged following rule change. This activation pattern declined with improving task performance reflecting rule acquisition. The vocabulary of letters comprising the exemplars was also periodically changed, independently of rule changes. This exemplar change modulated activation in left anterior hippocampus. Our finding that fronto-polar cortex mediates rule learning supports a functional contribution of this region to generic reasoning and problem-solving behaviours.
TL;DR: The hippocampal response to oddballs demonstrates a second‐order novelty effect, being sensitive to the “novelty of novelty” of oddball stimuli, and provides support for a more general theory that a function of the anterior hippocampus is to register mismatches between expectation and experience.
Abstract: An efficient memory system requires the ability to detect and preferentially encode novel stimuli. Human electrophysiological recordings demonstrate differential hippocampal responses to novel vs. familiar stimuli, as well as to oddball stimuli. Although functional imaging experiments of novelty detection have demonstrated hippocampal activation, oddball-evoked hippocampal activation has not been demonstrated. Here we use event-related functional magnetic resonance imaging (fMRI) to measure hippocampal responses to three types of oddball words: perceptual, semantic, and emotional. We demonstrate left anterior hippocampal sensitivity to all three oddball types, with adaptation of responses across multiple oddball presentations. This adaptive hippocampal oddball response was not modulated by depth of processing, suggesting a high degree of automaticity in the underlying process. However, an interaction with depth of encoding for semantic oddballs was evident in a more lateral left anterior hippocampal region. We conclude that the hippocampal response to oddballs demonstrates a second-order novelty effect, being sensitive to the "novelty of novelty" of oddball stimuli. The data provide support for a more general theory that a function of the anterior hippocampus is to register mismatches between expectation and experience.
TL;DR: The results suggest that GABAergic and cholinergic systems influence the neuronal plasticity necessary for repetition priming, using event-related functional magnetic resonance imaging.
Abstract: In this experiment we address the pharmacological modulation of repetition priming, a basic form of learning, using event-related functional magnetic resonance imaging. We measured brain activity in a word-stem completion paradigm in which, before study, volunteers were given either placebo, lorazepam (2 mg orally), or scopolamine (0.4 mg, i.v.). Relative to placebo, both drugs attenuated the behavioral expression of priming. Repetition was associated with a decreased neuronal response in left extrastriate, left middle frontal, and left inferior frontal cortices in the placebo group. Both drugs abolished these "repetition suppression" effects. By showing a concurrence of behavioral and neuronal modulations, the results suggest that GABAergic and cholinergic systems influence the neuronal plasticity necessary for repetition priming.
TL;DR: The time taken to identify a target on a changed-level trial is longer following four repeated-level trials compared to two repeated- level trials, but that runs of six do not produce additional costs over four, and targets can be identified faster following externally cued switches compared to internally mediated switches.
TL;DR: Responses to acoustic conditioned stimuli in auditory cortex were modulated by the presence of a visual context which signaled the likelihood of receiving an aversive unconditioned stimulus and this phenomenon was associated with enhanced activity in parietal cortex, which may reflect an increase in attention to the Presence of environmental threat stimuli.
Abstract: Responses to a stimulus signaling danger depend not only on the nature of that stimulus, but also on the context in which it is presented. A large body of work has been conducted in experimental animals investigating the neural correlates of contextual modulation of fear responses. However, much less is known about this process in humans. In this study we used functional MRI in a fear conditioning paradigm to explore this phenomenon. Responses to acoustic conditioned stimuli in auditory cortex were modulated by the presence of a visual context which signaled the likelihood of receiving an aversive unconditioned stimulus. Furthermore, the presence of the aversive visual context was associated with enhanced activity in parietal cortex, which may reflect an increase in attention to the presence of environmental threat stimuli.
TL;DR: This codon is homologous to a pathogenic presenilin 2 mutation with the same base change (ATG to GTG) and amino acid change (M239V) and causes disease with an exceptionally early onset age (approximately 30 years) in which pathological examination shows extensive Lewy bodies as well as plaques and tangles.
TL;DR: The findings suggest that peripheral autonomic denervation is associated with grey matter loss in cortical regions encompassing areas that have previously shown are functionally involved in generation and representation of bodily states of autonomic arousal.
Journal Article•
TL;DR: For instance, this paper showed that the perceived attractiveness of an unfamiliar face increases brain activity in the ventral striatum of the viewer when meeting the person's eye, and decreases activity when eye gaze is directed away.
Abstract: 1 , with the eyes assuming particular importance 2,3. Here we show that the perceived attractiveness of an unfamiliar face increases brain activity in the ventral striatum of the viewer when meeting the person's eye, and decreases activity when eye gaze is directed away. Depending on the direction of gaze, attractiveness can thus activate dopaminergic regions that are strongly linked to reward prediction 4 , indicating that central reward systems may be engaged during the initiation of social interactions. In an event-related functional magnetic resonance imaging (fMRI) study, 16 subjects (8 male, 8 female) were shown colour images of 40 different faces, which had their eyes directed either at or away from the subject (Fig. 1). After the fMRI scanning session, subjects rated the attractiveness of the faces they had seen, and these ratings were normalized and parametrically entered into the analysis. Significant effects (P<0.05, corrected for multiple comparisons) were assessed using a t-test and displayed as statistical parametric maps using SPM99b software. No brain region showed any activation in response to facial attractiveness per se. We therefore investigated whether processing of attractiveness depends on gaze direction. When eye gaze was directed at the subjects, activity in the ventral striatum correlated positively with attractiveness (slope: +0.46% change in signal intensity per standard deviation increase in attractiveness rating). In contrast, this correlation was reversed when eye gaze was averted, causing activity in the ventral striatum to decrease with increasing attractiveness (slope: ǁ0.88% signal intensity per s.d. increase in attractiveness). Figure 2 shows the resulting activation map when these two contrasts are combined as an interaction — for example, the contrast (correlation with attractiveness when eye contact is made) minus (correlation with attractiveness when no eye contact is made). In a fixed-effects analysis, the effect was significant at a voxel level (the smallest volume tested in our study) in the right ventral striatum (Pǃ0.015) and at cluster level bilaterally (right, P<0.01; left, Pǃ0.01). We also implemented a second-level random-effects analysis to determine whether the results could be extended to the population at large. Significant effects persisted at a cluster level in the right ventral striatum (P<0.01; point of maximal activation: xǃ12, yǃǁ8, zǃ10) and approached significance in the left ventral striatum (Pǃ0.06, xǃǁ10, yǃ0, zǃ4). The gender of the observed face in relation to the gender of the observer did not influence the response in the ventral striatum. This might indicate that …
Journal Article•
TL;DR: The results suggest that GABAergic and cholinergic systems influence the neuronal plasticity necessary for repetition priming, using event-related functional magnetic resonance imaging.
Journal Article•
TL;DR: In this article, the authors use a process model developed to explain confabulations following frontal lesions to interpret the ventrolateral versus dorsolateral dissociation in terms of cue specification versus retrieval monitoring.