Neuroscience
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Theories of emotion suggest a close relation of interoception and emotion. However, knowledge of underlying neuronal networks is still sparse. Repetitive transcranial magnetic stimulation (rTMS) is one neurostimulation method allowing causal conclusions between functions and brain regions via stimulation or inhibition of underlying brain structures. ⋯ Moreover, cardiac and respiratory IAc were positively associated with P3 amplitudes and negatively related to positive valence ratings. Positive associations of decreases of cardiac/respiratory IAc with decreases of arousal ratings and decreases of P3 amplitudes for negative stimuli after inhibition of the frontotemporal insular network and after inhibition of somatosensory cortices allow the conclusion of a causal relationship between reduced activity in interoceptive network structures and blunted emotional processing of visual stimuli. Our results suggest that both arousal, and valence aspects of emotional processing are disturbed after inhibition of interoceptive network structures, confirming core assumptions of peripheral theories of emotions and models of interoceptive predictive coding.
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Photoperiod and diet are factors known to modulate the hypothalamic-pituitary-adrenal (HPA) axis. Specifically, shifts in photoperiod have been previously linked with affective and anxiety disorders. Furthermore, isoflavones have been shown to mediate behavioral outcome in response to the environment of the animal. ⋯ Decreases in corticotrophin-releasing factor receptor 1 (CRFR1) mRNA expression were seen in animals fed the IF chow in the amygdala, prefrontal cortex and ventral hippocampus. These data suggest that alterations in CORT secretion following photoperiod alteration may be mediated through differences in CRFR1 gene expression or changes in MR:GR mRNA ratios. These findings provide insight into the potential mechanisms by which the HPA axis adapts to photoperiod and diet.
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There is now widespread consensus that social biases often influence actions independently of the actor's intention or awareness. The notion that we are sometimes blind to the origins of our thoughts, attitudes, and behaviors also features prominently in research into domain-general human memory systems, which has a long history of distinguishing between implicit and explicit repercussions of past experience. A shared challenge across these fields of study is thus to identify techniques for effectively managing the contents of our memory stores, particularly those aspects into which we have limited metacognitive insight. ⋯ A second body of work concerns breakthroughs in understanding memory consolidation, which determines the fate of newly encoded memories. We discuss the promise of each of these developments for identifying ways to become better stewards of our social minds. More generally, we suggest that, as with other forms of learning and memory, intentional practice and rehearsal may be critical in learning to minimize unwanted biases.
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High-definition transcranial direct current stimulation (HD-tDCS) is a variant of tDCS, which produces more focal stimulation, delimiting brain current flow to a defined region compared to conventional tDCS. To date, only one study has been conducted to investigate HD-tDCS effects on language recovery in aphasia. Here, we aimed to assess the effects of cathodal HD-tDCS on verb naming by comparing two current intensities: 1 vs 2 mA. ⋯ Our findings showed that HD-tDCS applied to the right intact hemisphere are efficacious for language recovery. These results indicate that HD-tDCS represents a promising new technique for language rehabilitation. However, systematic determination of stimulation intensity appears to be crucial for obtaining relevant effects.
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Schizophrenia is a severe mental disorder with numerous etiological susceptibilities. Maternal infection is a key risk factor for schizophrenia. Prenatal lipopolysaccharide (LPS) infection stimulates cytokine production that affects brain development. ⋯ The neuronal morphology of neurons in the VH in LPS-treated rats remained unaltered. Interestingly, the anxiogenic-related behavior correlated with neuronal hypertrophy observed in the BLA. Our findings suggest that the behavioral and neural modifications observed in our model could be mediated by the long-lasting alterations in Zn and NO levels in the brain.