Gina Rippon

Having a word with yourself: Neural correlates of self-criticism and self-reassurance

Self-criticism is strongly correlated with a range of psychopathologies, such as depression, eating disorders and anxiety. In contrast, self-reassurance is inversely associated with such psychopathologies. Despite the importance of self-judgements and evaluations, little is known about the neurophysiology of these internal processes. The current study therefore used a novel fMRI task to investigate the neuronal correlates of self-criticism and self-reassurance. Participants were presented statements describing two types of scenario, with the instruction to either imagine being self-critical or self-reassuring in that situation. One scenario type focused on a personal setback, mistake or failure, which would elicit negative emotions, whilst the second was of a matched neutral event. Self-criticism was associated with activity in lateral prefrontal cortex (PFC) regions and dorsal anterior cingulate (dAC), therefore linking self-critical thinking to error processing and resolution, and also behavioural inhibition. Self-reassurance was associated with left temporal pole and insula activation, suggesting that efforts to be self-reassuring engage similar regions to expressing compassion and empathy towards others. Additionally, we found a dorsal/ventral PFC divide between an individuals tendency to be self-critical or self-reassuring. Using multiple regression analyses, dorsolateral PFC activity was positively correlated with high levels of self-criticism (assessed via self-report measure), suggesting greater error processing and behavioural inhibition in such individuals. Ventrolateral PFC activity was positively correlated with high self-reassurance. Our findings may have implications for the neural basis of a range of mood disorders that are characterised by a preoccupation with personal mistakes and failures, and a self-critical response to such events.

Threat-Evoked Anxiety Disrupts Spatial Working Memory Performance: An Attentional Account

It is proposed that threat-evoked anxiety and spatial Working Memory (WM) rely on a common visuospatial attention mechanism. A prediction of this hypothesis is that spatial but not verbal WM should be disrupted in conditions of threat anxiety. Participants performed verbal and spatial n-back WM tasks in the presence or absence of threat of shock (shocks were not delivered). The presence of anxiety was assessed via heart rate recordings and self-report. Both measures clearly distinguished between WM blocks associated with threat of shock (Threat) and blocks, in which threat was absent (Safety). Performance on the spatial WM task was impaired in Threat relative to Safety. Furthermore, the more anxiety participants reported and the higher their heart rate in Threat compared to Safety, the more impaired was their spatial WM performance. This effect was not observed for verbal WM. The results indicate selective disruption of spatial WM performance by threat-evoked anxiety, interpreted in terms of more overlap in visuospatial attention between anxiety and spatial WM vs. anxiety and verbal WM.

Recommendations for sex/gender neuroimaging research: key principles and implications for research design, analysis, and interpretation

Neuroimaging (NI) technologies are having increasing impact in the study of complex cognitive and social processes. In this emerging field of social cognitive neuroscience, a central goal should be to increase the understanding of the interaction between the neurobiology of the individual and the environment in which humans develop and function. The study of sex/gender is often a focus for NI research, and may be motivated by a desire to better understand general developmental principles, mental health problems that show female-male disparities, and gendered differences in society. In order to ensure the maximum possible contribution of NI research to these goals, we draw attention to four key principles—overlap, mosaicism, contingency and entanglement—that have emerged from sex/gender research and that should inform NI research design, analysis and interpretation. We discuss the implications of these principles in the form of constructive guidelines and suggestions for researchers, editors, reviewers and science communicators.

Coarse threat images reveal theta oscillations in the amygdala: a magnetoencephalography study

Neurocognitive models propose a specialized neural system for processing threat-related information, in which the amygdala plays a key role in the analysis of threat cues. fMRI research indicates that the amygdala is sensitive to coarse visual threat relevant information—for example, low spatial frequency (LSF) fearful faces. However, fMRI cannot determine the temporal or spectral characteristics of neural responses. Consequently, we used magnetoencephalography to explore spatiotemporal patterns of activity in the amygdala and cortical regions with blurry (LSF) and normal angry, fearful, and neutral faces. Results demonstrated differences in amygdala activity between LSF threat-related and LSF neutral faces (50–250 msec after face onset). These differences were evident in the theta range (4–8 Hz) and were accompanied by power changes within visual and frontal regions. Our results support the view that the amygdala is involved in the early processing of coarse threat related information and that theta is important in integrating activity within emotion-processing networks.

Differences in working memory involvement in analytical and creative tasks: an ERP study

If, as suggested, creative (insight) problem solving is less systematic and employs less planning than analytical problem solving, the former requires substantially less working memory (WM) than the latter. Subjects simultaneously solved problems and counted auditory stimuli (concurrent WM task), in response to which ERPs were recorded. Counting disrupted analytical, but not creative performance. Peak and time-window average P300 were more frontal during analytical problem solving as compared to insight or counting tones only (control). A PCA extracted two factors in the P3 range, one frontal and one broad left-lateralized, which distinguished analytical from creative problem solving. The findings indicate distinct processing pathways for the two types of tasks with more WM involvement in analytical tasks.

Dynamic facial expressions evoke distinct activation in the face perception network: A connectivity analysis study

Very little is known about the neural structures involved in the perception of realistic dynamic facial expressions. In the present study, a unique set of naturalistic dynamic facial emotional expressions was created. Through fMRI and connectivity analysis, a dynamic face perception network was identified, which is demonstrated to extend Haxby et al.s [Haxby, J. V., Hoffman, E. A., & Gobbini, M. I. The distributed human neural system for face perception. Trends in Cognitive Science, 4, 223–233, 2000] distributed neural system for face perception. This network includes early visual regions, such as the inferior occipital gyrus, which is identified as insensitive to motion or affect but sensitive to the visual stimulus, the STS, identified as specifically sensitive to motion, and the amygdala, recruited to process affect. Measures of effective connectivity between these regions revealed that dynamic facial stimuli were associated with specific increases in connectivity between early visual regions, such as the inferior occipital gyrus and the STS, along with coupling between the STS and the amygdala, as well as the inferior frontal gyrus. These findings support the presence of a distributed network of cortical regions that mediate the perception of different dynamic facial expressions.

Individual differences in electrodermal and electroencephalographic asymmetries

In a continuing investigation of the relationship between differential hemispheric activation and electrodermal asymmetry, comparisons were made between the electroencephalographic asymmetries and electrodermal asymmetries exhibited by subjects carrying out particular tasks. Bilateral skin conductance responses and 28 channels of EEG data allowing the production of topographical maps were collected from 8 female and 8 male right-handed subjects during the performance of two tasks, one verbal and one visuospatial. The tasks were selected with the aim of differentially activating the hemispheres to investigate whether parallel changes in the direction of electroencephalographic and electrodermal asymmetries would occur. EEG asymmetries were compared in female and male subjects. Previous research has indicated that males tend to show stronger EEG asymmetry than females, and that this is emphasised in verbal tasks. This was confirmed by the present study. Comparison with electrodermal activity revealed a weak relationship between the two measures, with some parallels between task-related variations in the beta 2 waveband and skin conductance responses. No parallels between alpha activity or skin conductance level were demonstrated. If the subjects are regrouped according to degree of electrodermal asymmetries, then some closer parallels with electroencephalographic asymmetries are revealed with more marked electrodermal asymmetry paralleling more marked electroencephalographic asymmetry. Variations in electrodermal asymmetry appear to be related to greater activity on the hand contralateral to the hemisphere showing smaller amplitude EEG activity, generally in the beta waveband. In discussing cortical control of electrodermal activity, these findings are discussed in terms of both the contralateral excitatory and the contralateral inhibitory models.

Plasticity, plasticity, plasticity…and the rigid problem of sex

Why is popular understanding of female–male differences still based on rigid models of development, even though contemporary developmental sciences emphasize plasticity? Is it because the science of sex differences still works from the same rigid models?

A double-dissociation of English past-tense production revealed by event-related potentials and low-resolution electromagnetic tomography (LORETA)

OBJECTIVES Evidence of systematic double-dissociations of neural activity associated with the generation of regular and irregular past tense in healthy individuals may prove decisive in distinguishing between single- and dual-route models of morphological processing, because the former (connectionist models of morphological processing) have only been able to simulate double-dissociations of past-tense morphology as low-probability phenomena. METHODS Twenty-eight channel event-related potentials (ERPs) were recorded in response to past-tense production and subsequently analyzed using a 3-stage strategy. RESULTS A data-driven algorithm temporally segmented the ERPs into 16 distinct epochs of stable field configuration (microstates). A space-oriented brain electric field analysis determined that one of those epochs, 288-321 ms after the verb stem presentation, showed significant differences between the regular and irregular verb conditions. As a further test of these results, a novel source localization technique that computes 3-dimensional distribution of cortical current density in the Talairach brain atlas--low-resolution electromagnetic tomography--found in the above microstate more activity for regulars in the right prefrontal and right temporal areas and for irregulars in the left temporal areas and the anterior cingulate cortex, which can be taken as evidence of systematic double-dissociation. CONCLUSIONS The present results achieved with a source localization technique provide evidence of a two-way compartmentalization of neural activity corresponding to regular and irregular past tense, thus corroborating the dual-mechanism character of verb morphology.

The lateral and ventromedial prefrontal cortex work as a dynamic integrated system: Evidence from fmri connectivity analysis

Recent functional magnetic resonance imaging (fMRI) investigations of the interaction between cognition and reward processing have found that the lateral prefrontal cortex (PFC) areas are preferentially activated to both increasing cognitive demand and reward level. Conversely, ventromedial PFC (VMPFC) areas show decreased activation to the same conditions, indicating a possible reciprocal relationship between cognitive and emotional processing regions. We report an fMRI study of a rewarded working memory task, in which we further explore how the relationship between reward and cognitive processing is mediated. We not only assess the integrity of reciprocal neural connections between the lateral PFC and VMPFC brain regions in different experimental contexts but also test whether additional cortical and subcortical regions influence this relationship. Psychophysiological interaction analyses were used as a measure of functional connectivity in order to characterize the influence of both cognitive and motivational variables on connectivity between the lateral PFC and the VMPFC. Psychophysiological interactions revealed negative functional connectivity between the lateral PFC and the VMPFC in the context of high memory load, and high memory load in tandem with a highly motivating context, but not in the context of reward alone. Physiophysiological interactions further indicated that the dorsal anterior cingulate and the caudate nucleus modulate this pathway. These findings provide evidence for a dynamic interplay between lateral PFC and VMPFC regions and are consistent with an emotional gating role for the VMPFC during cognitively demanding tasks. Our findings also support neuropsychological theories of mood disorders, which have long emphasized a dysfunctional relationship between emotion/motivational and cognitive processes in depression.