The neural correlates of ongoing conscious thought.

A core goal in cognitive neuroscience is identifying the physical substrates of the patterns of thought that occupy our daily lives. Contemporary views suggest that the landscape of ongoing experience is heterogeneous and can be influenced by features of both the person and the context. This perspective piece considers recent work that explicitly accounts for both the heterogeneity of the experience and context dependence of patterns of ongoing thought. These studies reveal that systems linked to attention and control are important for organizing experience in response to changing environmental demands. These studies also establish a role of the default mode network beyond task-negative or purely episodic content, for example, implicating it in the level of vivid detail in experience in both task contexts and in spontaneous self-generated experiential states. Together, this work demonstrates that the landscape of ongoing thought is reflected in the activity of multiple neural systems, and it is important to distinguish between processes contributing to how the experience unfolds from those linked to how these experiences are regulated.

Valence and ownership: object desirability influences self-prioritization.

Research has demonstrated that possession exerts a potent influence on stimulus processing, such that objects are categorized more rapidly when owned-by-self than when they belong to other people. Outstanding theoretical questions remain, however, regarding the extent of this self-prioritization effect. In particular, does ownership enhance the processing of objects regardless of their valence or is self-prioritization restricted to only desirable items? To address this issue, here we explored the speed with which participants categorized objects (i.e., desirable and undesirable posters) that ostensibly belonged to the self and a best friend. In addition, to identify the cognitive processes supporting task performance, data were submitted to a hierarchical drift-diffusion model (HDDM) analysis. The results revealed a self-prioritization effect (i.e., RTself < RTfriend) for desirable posters that was underpinned by differences in the efficiency of stimulus processing. Specifically, decisional evidence was extracted more rapidly from self-owned posters when they were desirable than undesirable, an effect that was reversed for friend-owned posters. These findings advance understanding of when and how valence influences self-prioritization during decisional processing.

Word up - Experiential and neurocognitive evidence for associations between autistic symptomology and a preference for thinking in the form of words.

Autism symptomology has a profound impact on cognitive and affective functioning, yet we know relatively little about how it shapes patterns of ongoing thought. In an exploratory study in a large population of neurotypical individuals, we used experience sampling to characterise the relationship between ongoing cognition and self-reported autistic traits. We found that with increasing autistic symptom score, cognition was characterised by thinking more in words than images. Analysis of structural neuroimaging data found that autistic traits linked to social interaction were associated with greater cortical thickness in a region of lingual gyrus (LG) within the occipital cortex. Analysis of resting state functional neuroimaging data found autistic traits were associated with stronger connectivity between the LG and a region of motor cortex. Importantly, the strength of connectivity between the LG and motor cortex moderated the link between autistic symptoms and thinking in words: individuals showing higher connectivity showed a stronger association between autistic traits and thinking in words. Together we provide behavioural and neural evidence linking autistic traits to the tendency to think in words which may be rooted in underlying cortical organisation. These observations lay the groundwork for research into the form and content of self-generated thoughts in individuals with the established diagnosis of autism.

Parts of me: Identity-relevance moderates self-prioritization.

Recent research has revealed a pervasive bias for self-relevant information during decision-making, a phenomenon termed the self-prioritization effect. Focusing almost exclusively on between-target (e.g., self vs. friend) differences in task performance, however, this work has overlooked the influence stimulus factors potentially exert during decisional processing. Accordingly, based on pertinent social-psychological theorizing (i.e., Identity-Based Motivation Theory), here we explored the possibility that self-prioritization is sensitive to the identity-based relevance of stimuli. The results of three experiments supported this hypothesis. In a perceptual-matching task, stimulus enhancement was greatest when geometric shapes were associated with identity-related information that was important (vs. unimportant) to participants. In addition, hierarchical drift-diffusion modeling revealed this effect was underpinned by differences in the efficiency of visual processing. Specifically, evidence was extracted more rapidly from stimuli paired with consequential compared to inconsequential identity-related components. These findings demonstrate how identity-relevance moderates self-prioritization.

Stop stereotyping.

Restraining the expression of stereotypes is a necessary requirement for harmonious living, yet surprisingly little is known about the efficacy of this process. Accordingly, in two experiments, here we used a stop-signal task to establish how effectively stereotype-related responses can be inhibited. In Experiment 1, following the presentation of gender-typed occupational contexts, participants reported the sex of target faces (i.e., Go trials) unless an occasional auditory tone indicated they should withhold their response (i.e., Stop trials). In Experiment 2, following the presentation of male and female faces, participants made either stereotypic or counter-stereotypic judgments, unless a stop signal was presented. Regardless of whether stereotyping was probed indirectly (Experiment 1) or directly (Experiment 2), a consistent pattern of results was observed; inhibition was faster for stereotypic compared with counter-stereotypic responses. These findings demonstrate that stopping stereotyping may be less challenging than has widely been assumed.

Neural connectivity of alexithymia: Specific association with major depressive disorder.

BACKGROUND: Alexithymia has been frequently associated with major depression disorders (MDD). Yet little is known about the exact relationship of alexithymia and MDD. In order to explore this subject matter, the neural connectivity associated with alexithymia in people with MDD and matched nonclinical controls were compared. METHODS: Twenty-two females diagnosed with first-episode MDD and twenty-one matched nonclinical controls were MRI brain-scanned with diffusion-tensor-imaging and resting-state-functional-imaging methods, and self-reported the Chinese 20-item Toronto Alexithymia Scale. RESULTS: Voxel-wise multiple regression analysis showed a group interaction effect regarding the correlation between white-matter-connectivity and alexithymia. Significant correlations were observed at the corpus-callosum in MDDs and at the right superior-longitudinal-fasciculus in the controls. These findings were then used to derive seeds for analyzing resting-state-functional-connectivity in each group separately. The results further revealed that alexithymia in MDDs were associated with reduced functional-connectivity in the right precentral-gyrus and several regions of the brain on the right which are associated with cognitive regulation in the default-mode-network. In contrast, among the control subjects, alexithymia was correlated with increased functional-connectivity between the right inferior-frontal-gyrus-triangularis and the right superior-occipital-lobe, which is associated with emotional response to external stimuli. LIMITATIONS: Better participant selection, especially recruitment of medication-free samples, and the engagement of additional alexithymia assessments, should be considered in future investigations. CONCLUSIONS: These findings supported our a priori hypothesis that MDDs and controls have distinct white-matter correlates of alexithymia, and these corresponded to the existing proposed neural correlates for the cognitive and affective characteristics of alexithymia respectively. Extended impacts of these microstructural changes on remote functional networks might help explain the distinct behavioral characteristics of alexithymia for these groups, as well as implications for therapeutic intervention of MDD.

Mindfulness Trait Predicts Neurophysiological Reactivity Associated with Negativity Bias: An ERP Study.

This study explored the relationship of mindfulness trait with the early and late stages of affective processing, by examining the two corresponding ERP components, P2 and LPP, collected from twenty-two male Chinese participants with a wide range of meditation experiences. Multiple regression analyses was performed on the mindfulness scores, as measured by CAMS-R, with the subjective affective ratings and ERP data collected during an emotion processing task. The results showed that increased mindfulness scores predicted increased valence ratings of negative stimuli (less negative), as well as increased P2 amplitudes at the frontocentral location for positive compared to negative stimuli. Based on these findings, a plausible mechanism of mindfulness in reducing negativity bias was discussed. Moreover, our results replicated previous findings on the age-related increase of P2 amplitudes at the frontal sites for positive compared to neutral stimuli. Since the locations at which P2 amplitudes were found as associated with age and mindfulness differed, as did the emotional contents of the stimuli being compared, indicating that the effect of age did not confound our findings on mindfulness and the two factors might operate on early affective processing from distinct sources and mechanisms.

Alexithymia: the story of a survivor of childhood traumatic brain injury.

INTRODUCTION: Affective abnormalities resulting from traumatic brain injuries can pose major threats to the long-term outcomes of neurorehabilitation, especially when they have gone unattended in the process of rehabilitation. This study reports a case of a 46-year-old woman who survived a severe traumatic brain injury to the right occipital cortex (BA18/19) at the age of 10. While her cognitive recovery was remarkable, she has been living with a significant affective disturbance: difficulty with feeling others' feelings. METHOD: Neuropsychological tests and self-reported questionnaires capturing the patient's neuropsychological profile, social cognitive abilities, emotional responses, affective awareness and visual imager were administered to the patient. RESULTS: While cognitive functioning beside attention has recovered well, findings clearly indicate that she is indeed suffering from a high level of alexithymia. CONCLUSION: It is speculated that the alexithymia observed may relate to the damage to the visual cortex, which is an important neural substrate for visual imagery and/or damage to the bottom-up stimulus-driven attention system in the right hemisphere. This case exemplified a possible organic basis of social affective disturbance, which may be overlooked in the process of neurorehabilitation.