[Show abstract][Hide abstract] ABSTRACT: Several studies have investigated the neural basis of effortful emotion regulation (ER) but the neural basis of automatic ER has been less comprehensively explored. The present study investigated the neural basis of automatic ER supported by ‘implementation intentions’. 40 healthy participants underwent fMRI while viewing emotion-eliciting images and used either a previously-taught effortful ER strategy, in the form of a goal intention (e.g., try to take a detached perspective), or a more automatic ER strategy, in the form of an implementation
intention (e.g., “If I see something disgusting, then I will think these are just pixels on the screen!”), to regulate their emotional response. Whereas goal intention ER strategies were associated with activation of brain areas previously reported to be involved in effortful ER (including dorsolateral prefrontal cortex), ER strategies based on an implementation intention strategy were associated with activation of right inferior frontal gyrus and ventro-parietal cortex, which may reflect the attentional control processes automatically captured by the cue for action contained within the implementation intention. Goal intentions were also associated with less effective modulation of left amygdala, supporting the increased efficacy of ER under implementation intention instructions, which showed coupling of orbitofrontal cortex and amygdala. The findings support previous behavioural studies in suggesting that forming an implementation intention enables people to enact goal-directed responses with less effort and more efficiency.
PLoS ONE 03/2015; 10(3). DOI:10.1371/journal.pone.0119500 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Self-deception and impression-management comprise two types of deceptive, but generally socially acceptable behaviours, which are common in everyday life as well as being present in a number of psychiatric disorders. We sought to establish and dissociate the ‘normal’ brain substrates of self-deception and impression-management. Twenty healthy participants underwent fMRI scanning at 3T whilst completing the ‘Balanced Inventory of Desirable Responding’ test under two conditions: ‘fake good’, giving the most desirable impression possible and ‘fake bad’ giving an undesirable impression. Impression-management scores were more malleable to manipulation via ‘faking’ than self-deception scores. Response times to self-deception questions and ‘fake bad’ instructions were significantly longer than to impression-management questions and ‘fake good’ instructions respectively. Self-deception and impression-management manipulation and ‘faking bad’ were associated with activation of medial prefrontal cortex (mPFC) and left ventrolateral prefrontal cortex (vlPFC). Impression-management manipulation was additionally associated with activation of left dorsolateral prefrontal cortex and left posterior middle temporal gyrus. ‘Faking bad’ was additionally associated with activation of right vlPFC, left temporo-parietal junction and right cerebellum. There were no supra-threshold activations associated with ‘faking good’. Our neuroimaging data suggest that manipulating self-deception and impression-management and more specifically ‘faking bad’ engages a common network comprising mPFC and left vlPFC. Shorter response times and lack of dissociable neural activations suggests that ‘faking good’, particularly when it comes to impression-management, may be our most practiced ‘default’ mode.
[Show abstract][Hide abstract] ABSTRACT: Discerning a speaker's gender from their voice is a basic and crucial aspect of human communication. Voice pitch height, the perceptual correlate of fundamental frequency, is higher in females and provides a cue for gender discrimination. However, male and female voices are also differentiated by multiple other spectral and temporal characteristics, including mean formant frequency and spectral flux. The robust perceptual segregation of male and female voices is thought to result from processing the combination of discriminating features, which in neural terms may correspond to early sound object analysis occurring in non-primary auditory cortex. However, the specific mechanism for gender perception has been unclear. Here, using functional magnetic resonance imaging, we show that discrete sites in non-primary auditory cortex are differentially activated by male and female voices, with female voices consistently evoking greater activation in the upper bank of the superior temporal sulcus and posterior superior temporal plane. This finding was observed at the individual subject-level in all 24 subjects. The neural response was highly specific: no auditory regions were more activated by male than female voices. Further, the activation associated with female voices was 1) larger than can be accounted for by a sole effect of fundamental frequency, 2) not due to psychological attribution of female gender and 3) unaffected by listener gender. These results demonstrate that male and female voices are represented as distinct auditory objects in the human brain, with the mechanism for gender discrimination being a gender-dependent activation-level cue in non-primary auditory cortex.
[Show abstract][Hide abstract] ABSTRACT: Studies investigating the neurophysiological basis of intrapersonal emotion regulation (control of one's own emotional experience) report that the frontal cortex exerts a modulatory effect on limbic structures such as the amygdala and insula. However, no imaging study to date has examined the neurophysiological processes involved in interpersonal emotion regulation, where the goal is explicitly to regulate another person's emotion. Twenty healthy participants (10 males) underwent fMRI while regulating their own or another person's emotions. Intrapersonal and interpersonal emotion regulation tasks recruited an overlapping network of brain regions including bilateral lateral frontal cortex, pre-supplementary motor area, and left temporo-parietal junction. Activations unique to the interpersonal condition suggest that both affective (emotional simulation) and cognitive (mentalizing) aspects of empathy may be involved in the process of interpersonal emotion regulation. These findings provide an initial insight into the neural correlates of regulating another person's emotions and may be relevant to understanding mental health issues that involve problems with social interaction.
Frontiers in Human Neuroscience 06/2014; 8:376. DOI:10.3389/fnhum.2014.00376 · 2.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Gravitational forces may lead to local changes in subarachnoid cerebrospinal fluid (CSF) layer thickness, which has important implications for neurophysiological modulation and recording techniques. This study examines the effect of gravitational pull associated with different head positions on the distribution of subarachnoid CSF using structural magnetic resonance imaging. Images of seven subjects in three different positions (supine, left lateral and prone) were statistically compared. Results suggest that subarachnoid CSF volume decreases on the side of the head closest to the ground, due to downward brain movement with gravity. These findings warrant future research into currently unexplored gravitation-induced changes in regional subarachnoid CSF thickness.
[Show abstract][Hide abstract] ABSTRACT: Subjective assessment of emotional valence is typically associated with both brain activity and autonomic arousal. Accurately assessing emotional salience is particularly important when perceiving threat. We sought to characterize the neural correlates of the interaction between behavioral and autonomic responses to potentially threatening visual and auditory stimuli. Twenty-five healthy male subjects underwent fMRI scanning whilst skin conductance responses (SCR) were recorded. One hundred and eighty pictures, sentences, and sounds were assessed as "harmless" or "threatening." Individuals' stimulus-locked, phasic SCRs and trial-by-trial behavioral assessments were entered as regressors into a flexible factorial design to establish their separate autonomic and behavioral neural correlates, and convolved to examine psycho-autonomic interaction (PAI) effects. Across all stimuli, "threatening," compared with "harmless" behavioral assessments were associated with mainly frontal and precuneus activation with specific within-modality activations including bilateral parahippocampal gyri (pictures), bilateral anterior cingulate cortex (ACC) and frontal pole (sentences), and right Heschl's gyrus and bilateral temporal gyri (sounds). Across stimulus modalities SCRs were associated with activation of parieto-occipito-thalamic regions, an activation pattern which was largely replicated within-modality. In contrast, PAI analyses revealed modality-specific activations including right fusiform/parahippocampal gyrus (pictures), right insula (sentences), and mid-cingulate gyrus (sounds). Phasic SCR activity was positively correlated with an individual's propensity to assess stimuli as "threatening." SCRs may modulate cognitive assessments on a "harmless-threatening" dimension, thereby modulating affective tone and hence behavior.
Frontiers in Human Neuroscience 01/2012; 6:349. DOI:10.3389/fnhum.2012.00349 · 2.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The perception and judgement of social hierarchies forms an integral part of social cognition. Hierarchical judgements can be either self-referential or allocentric (pertaining to two or more external agents). In psychiatric conditions such as dissocial personality disorder and schizophrenia, the impact of hierarchies may be problematic. We sought to elucidate the brain regions involved in judging allocentric social hierarchies. Twenty-two healthy male subjects underwent three fMRI scans. During scanning, subjects answered questions concerning visually-presented target pairs of human individual's relative superiority within a specific social hierarchy or their perceived degree of social alliance (i.e., whether they were "friends or enemies"). Subjects also made judgements relating to target pairs' age, gender and fame to control for confounding factors and performed a baseline numerical task. Response times increased in line with hypothesized ascending executive load. Both social hierarchy and social alliance judgements activated left ventrolateral prefrontal cortex (VLPFC), left dorsal inferior frontal gyrus (IFG) and bilateral fusiform gyri. In addition, social alliance judgements activated right dorsal IFG and medial prefrontal cortex. When compared directly with social alliance, social hierarchy judgements activated left orbitofrontal cortex. Detecting the presence of social hierarchies and judging other's relative standing within them implicates the cognitive executive, in particular the VLPFC. Our finding informs accounts of 'normal' social cognition but our method also provides a means of probing the dissocial brain in personality disorder and schizophrenia where executive function may be dysfunctional.
[Show abstract][Hide abstract] ABSTRACT: Investigating auditory hallucinations that occur in health may help elucidate brain mechanisms which lead to the pathological experience of auditory hallucinations in neuropsychiatric disorders such as schizophrenia. In this study, we investigated healthy individuals who reported auditory hallucinations whilst falling asleep (hypnagogic hallucinations; HG) and waking up (hypnopompic hallucinations; HP). In an initial behavioural study, we found that subjects with a history of auditory HG/HP hallucinations (n = 26) reported significantly greater subjective sensitivity to environmental sounds than non-hallucinator controls (n = 74). Then, two fMRI experiments were performed. The first examined speech-evoked brain activation in 12 subjects with a history of auditory HG/HP hallucinations and 12 non-hallucinator controls matched for age, gender and IQ. The second fMRI experiment, in the same subjects, probed how brain activation was modulated by auditory attention using a bimodal selective attention paradigm. In the first experiment, the hallucinator group demonstrated significantly greater speech-evoked activation in the left supramarginal gyrus than the control group. In the second experiment, directing attention towards the auditory (vs. visual) modality induced significantly greater activation of the anterior cingulate gyrus in the hallucinator group than in the control group. These results suggest that hallucination proneness is associated with increased sensitivity of auditory and polysensory association cortex to auditory stimulation, an effect which might arise due to enhanced attentional bias from the anterior cingulate gyrus. Our data support the overarching hypothesis that top-down modulation of auditory cortical response characteristics may be a key mechanistic step in the generation of auditory hallucinations.
[Show abstract][Hide abstract] ABSTRACT: In the executive model of deception, the telling of a lie necessitates the inhibition of a veridical prepotent response (the truth), and such inhibition incurs a temporal penalty, manifest as a longer response time. If memory processes are engaged in generating such truths, then memory function should affect truthful and deceptive response times. To investigate this we examined the relationship between performance on a semantic knowledge deception task and a test of verbal memory in 40 college students. We found that verbal memory performance differentially affects the temporal parameters of truth and deception.
The American Journal of Psychology 12/2010; 123(4):447-53. · 1.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Our ability to interact physically with objects in the external world critically depends on temporal coupling between perception and movement (sensorimotor timing) and swift behavioral adjustment to changes in the environment (error correction). In this study, we investigated the neural correlates of the correction of subliminal and supraliminal phase shifts during a sensorimotor synchronization task. In particular, we focused on the role of the cerebellum because this structure has been shown to play a role in both motor timing and error correction. Experiment 1 used fMRI to show that the right cerebellar dentate nucleus and primary motor and sensory cortices were activated during regular timing and during the correction of subliminal errors. The correction of supraliminal phase shifts led to additional activations in the left cerebellum and right inferior parietal and frontal areas. Furthermore, a psychophysiological interaction analysis revealed that supraliminal error correction was associated with enhanced connectivity of the left cerebellum with frontal, auditory, and sensory cortices and with the right cerebellum. Experiment 2 showed that suppression of the left but not the right cerebellum with theta burst TMS significantly affected supraliminal error correction. These findings provide evidence that the left lateral cerebellum is essential for supraliminal error correction during sensorimotor synchronization.
[Show abstract][Hide abstract] ABSTRACT: The clock drawing (CD) task involves visual integration skills associated with parietal lobe function. Seven mild Alzheimer's Disease (AD) patients and 11 healthy elderly controls (EC) underwent functional magnetic resonance imaging (fMRI) scanning while viewing a radial motion (RM) task. This RM task in EC activated the bilateral secondary visual cortex and parietal regions, whereas AD patients activated only the right-sided secondary visual cortex. The magnitude of the fMRI signal in the left superior parietal lobe was positively correlated with performance on the CD task in AD patients. These findings suggest that complex visuospatial processing impairments reflect the underlying AD neuropathology in parietal regions.
The International journal of neuroscience 05/2010; 120(5):335-43. DOI:10.3109/00207450903320339 · 1.52 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Visuospatial impairments are known to occur in Alzheimer's disease (AD). We hypothesised that functional magnetic resonance imaging (fMRI) response in task-related brain regions would be impaired in patients with AD during the task and that treatment with acetyl cholinesterase inhibitors would enhance activations in brain regions concerned with this visual perceptual processing.
Ten AD subjects were neuropsychologically assessed and underwent fMRI imaging whilst performing a series of visuospatial perception tasks, before and after treatment with acetyl cholinesterase inhibitors. Eleven healthy elderly comparison subjects were also scanned twice.
Regions of increased brain activation in AD included the left precuneus, left cuneus, left supramarginal gyrus, right parieto-temporal cortex and right inferior parietal lobule. Further, increased activation in the left precuneus was found to correlate significantly with improved functioning of activities of daily living.
We believe this to be the first fMRI study that, after controlling for the confound of repeat scanning, demonstrates altered patterns of brain activation associated with visuospatial processing following treatment in patients with AD. The treatment-related improvement of visual perception in AD may rely on enhanced attentional mechanisms, thereby possibly supporting independent living through improvement on activities of daily living.
[Show abstract][Hide abstract] ABSTRACT: The neural basis of visuospatial deficits in Alzheimer's disease is unclear. We wished to investigate the neural basis of visuospatial perception in patients with Alzheimer's disease compared with healthy elderly comparison subjects using functional magnetic resonance imaging (fMRI). Twelve patients with AD and thirteen elderly comparison subjects were investigated. The patients were recruited from the local clinic and comparison subjects were from spouses and community. All participants underwent fMRI whilst viewing visuospatial stimuli and structural MRI, and findings were analysed using voxel-based morphometry. The comparison group activated V5, superior parietal lobe, parieto-occipital cortex and premotor cortices. The AD group demonstrated hypoactivation in the above regions and instead showed greater activation in inferior parietal lobule and activated additional areas. There was no structural atrophy above and beyond that found globally in patients in the identified regions of BOLD activation. To our knowledge, this is the first study to explore the neuroanatomy of perception of depth and motion in Alzheimer's disease. These specific functional deficits in AD provide evidence for an underlying patho-physiological basis for the clinically important symptom of visuospatial disorientation in patients with AD.
Psychiatry Research 06/2009; 172(2):109-16. DOI:10.1016/j.pscychresns.2008.11.002 · 2.47 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Limited behavioural repertoire impacts quality of life in chronic schizophrenia. We have previously shown that the amount of movement exhibited by patients with schizophrenia is positively correlated with the volume of left anterior cingulate cortex and that this quantity of movement can be increased by modafinil. However, increased movement in itself may be of limited clinical significance. Hence, we sought to analyse the 'structure' of spontaneous movement in patients with schizophrenia and to examine whether the chunking of spontaneous activity has a neuroanatomical basis. 'Actiwatches' were used to record spontaneous motor activity over a 20 hour period in sixteen male patients with schizophrenia. Time-series data were analysed for the number of discrete spontaneous activities, which might indicate a degree of structure to ongoing activity. Subjects underwent a whole-brain structural MRI scan. The 'number of discrete movement epochs' correlated with volumes of regions within bilateral rostro-ventral putamen and temporal poles. These data suggest that in people with schizophrenia the volume of bilateral putamen may influence the complexity of their behaviours, as distinct from the overall amount of behaviour. The results are presented in the context of a large body of previous research examining the role of the basal ganglia in motor and cognitive pattern generation.
The Open Neuroimaging Journal 02/2009; 3:48-53. DOI:10.2174/1874440000903010048
[Show abstract][Hide abstract] ABSTRACT: Schizophrenia is a severe, chronic, often disabling mental illness with onset characteristically in early adulthood. This article reviews the historical concepts of schizophrenia by Kraepelin and Bleuler, and discusses recent developments in the aetiology of schizophrenia, with an emphasis on the interplay between biological, psychological, and social factors. Genetic factors play an important role in the aetiology, as they ‘programme’ the early development of the brain’s structure, including the neurotransmitter receptor systems. According to the stress–vulnerability model, environmental stress and high ‘expressed emotion’ can precipitate the onset as well as influence the course and outcome of the illness. Cannabis abuse has a significant impact on the risk of schizophrenia, particularly in individuals with biological vulnerability to develop the illness. Clinically, patients with schizophrenia present with symptoms comprising positive (first-rank) and negative symptoms.
[Show abstract][Hide abstract] ABSTRACT: To identify factors significantly associated with post-traumatic stress disorder (PTSD), anxiety, and depression at 3 months post-injury; to develop a generic model to predict the occurrence of PTSD, anxiety, and depression at 3 months post-injury; and to validate this model in a test data set of patients.
Prospective cohort study.
Participants were 823 patients attending an emergency department (ED) following accidental injury. Baseline questionnaires were completed, with 1 and 3 months postal follow-ups. Predictor variables demonstrating significant associations with two of the three outcome measures (3-month HAD anxiety and depression scores and PTSD symptoms) were included in multivariate regression models for each outcome. Non-significant predictor variables were removed until all remaining independent variables made the most significant contribution to each of the three models. Models were validated using a test dataset.
Previous history of mental health problems, neuroticism score and having PTSD symptoms at 1 month predicted adverse outcomes at 3 months. When used on the test datasets, the areas under the receiver operating curve (ROC) curve for the models predicting outcomes at 3 months were: PTSD=0.91 (sensitivity=88.5%); anxiety=0.87 (sensitivity=93.7%); and depression=0.87 (sensitivity=96.7%).
The final model performed moderately well across the three outcomes and may be useful clinically as a generic rule-out tool to identify those who will not require follow up, watchful waiting or intervention.
British Journal of Clinical Psychology 10/2008; 48(Pt 1):31-45. DOI:10.1348/014466508X344799 · 1.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.
[Show abstract][Hide abstract] ABSTRACT: The management of dysplasia-associated lesional mass (DALM) and adenoma-like mass (ALM) in chronic ulcerative colitis (CUC) differs radically, involving total pan-proctocolectomy vs endoscopic resection and surveillance. Such lesions cannot be reliably differentiated using conventional colonoscopy. Confocal laser scanning imaging enables in vivo surface and subsurface cellular resolution imaging during ongoing video endoscopy. The aim of this study was to prospectively assess the clinical applicability and predictive power of the Pentax EC3870K endomicroscope for the in vivo differentiation of ALM and DALM in CUC during ongoing videocolonoscopy.
Patients were recruited who had a diagnosis of ALM or DALM within the previous 16 weeks. Confocal laser endomicroscopic (CLE) imaging of the circumscribed lesion and 4 adjacent mucosal segments was performed. Targeted biopsy with and without tissue sampling with endoscopic mucosal resection was performed and compared with conventional histopathology as the gold standard.
Thirty-six patients with 36 lesions fulfilled the study entry criteria. Using modified Mainz criteria for the in vivo diagnosis of ALM and DALM, the kappa coefficient of agreement between CLE and histopathologic evaluation was 0.91, and accuracy was 97% (95% confidence interval = 86%-99%).
This is the first study addressing the novel application of the Pentax EC3870K endomicroscopy system for the in vivo differentiation of ALM and DALM during ongoing video colonoscopy in CUC. We have shown that ALM and DALM can be differentiated with a high overall accuracy, enabling the safe selection of patients suitable for endoluminal resection versus immediate referral for pan-proctocolectomy.
Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 11/2007; 5(10):1235-41. DOI:10.1016/j.cgh.2007.06.003 · 7.90 Impact Factor