Science posts

See science posts on page 65 below.

    • 2005
    • Patrik Vuilleumier
    • How brains beware: neural mechanisms of emotional attention
    • Emotional processes not only serve to record the value of sensory events, but also to elicit adaptive responses and modify perception. Recent research using functional brain imaging in human subjects has begun to reveal neural substrates by which sensory processing and attention can be modulated by the affective significance of stimuli. The amygdala plays a crucial role in providing both direct and indirect top-down signals on sensory pathways, which can influence the representation of emotional events, especially when related to threat. These modulatory effects implement specialized mechanisms of ‘emotional attention’ that might supplement but also compete with other sources of top-down control on perception. This work should help to elucidate the neural processes and temporal dynamics governing the integration of cognitive and affective influences in attention and behaviour.
    • 2004
    • David Sander
    • Emotion and attention interactions in social cognition: Brain regions involved in processing anger prosody
    • Multiple levels of processing are thought to be involved in the appraisal of emotionally relevant events, with some processes being engaged relatively independently of attention, whereas other processes may depend on attention and current task goals or context. We conducted an event-related fMRI experiment to examine how processing angry voice prosody, an affectively and socially salient signal, is modulated by voluntary attention. To manipulate attention orthogonally to emotional prosody, we used a dichotic listening paradigm in which meaningless utterances, pronounced with either angry or neutral prosody, were presented simultaneously to both ears on each trial. In two successive blocks, participants selectively attended to either the left or right ear and performed a gender-decision on the voice heard on the target side. Our results revealed a functional dissociation between different brain areas. Whereas the right amygdala and bilateral superior temporal sulcus responded to anger..
    • 1999
    • Richard J. Davidson
    • The functional neuroanatomy of emotion and affective style
    • Recently, there has been a convergence in lesion and neuroimaging data in the identification of circuits underlying positive and negative emotion in the human brain. Emphasis is placed on the prefrontal cortex (PFC) and the amygdala as two key components of this circuitry. Emotion guides action and organizes behavior towards salient goals. To accomplish this, it is essential that the organism have a means of representing affect in the absence of immediate elicitors. It is proposed that the PFC plays a crucial role in affective working memory. The ventromedial sector of the PFC is most directly involved in the representation of elementary positive and negative emotional states while the dorsolateral PFC may be involved in the representation of the goal states towards which these elementary positive and negative states are directed. The amygdala has been consistently identified as playing a crucial role in both the perception of emotional cues and the production of emotional responses,..
    • 1998
    • Richard J. Davidson
    • Affective Style and Affective Disorders: Perspectives from Affective Neuroscience
    • Individual differences in emotional reactivity or affective style can be decomposed into more elementary constituents. Several separable of affective style are identified such as the threshold for reactivity, peak amplitude of response, the rise time to peak and the recovery time. latter two characteristics constitute components of affective chronometry The circuitry that underlies two fundamental forms of motivation and and withdrawal-related processes-is described. Data on differences in functional activity in certain components of these are next reviewed, with an emphasis on the nomological network of surrounding individual differences in asymmetric prefrontal The relevance of such differences for understanding the nature affective dysfunction in affective disorders is then considered. The ends by considering what the prefrontal cortex “does” in certain of affective style and highlights some of the important questions for future research.
    • 2003
    • Martha Ann Bell
    • Cognition and affective style: Individual differences in brain electrical activity during spatial and verbal tasks
    • Relations between brain electrical activity and performance on two cognitive tasks were examined in a normal population selected to be high on self-reported measures of Positive or Negative Affectivity. Twenty-five right-handed women, from an original pool of 308 college undergraduates, were the participants. EEG was recorded during baseline and during psychometrically matched spatial and verbal tasks. As predicted, participants who were high in Positive Affectivity performed equally well on the verbal and spatial tasks, while participants who were high in Negative Affectivity had spatial scores that were lower than their verbal scores. There were no group differences in baseline EEG. Both groups exhibited left central activation (i.e., α suppression) during the verbal and spatial tasks. When EEG data were analyzed separately for the group high in Positive Affectivity, there was evidence of parietal activation for the spatial task relative to the verbal task. The EEG data for the gro..
    • 2013
    • Dezso Nemeth
    • Social Communication Impairs Working-Memory Performance
    • Performance on working-memory tests is frequently used in experimental psychology and neuroscience, as well as in neuropsychological testing and clinical screening. It can be strongly affected by the social context and the communication style of the experimenter. We tested this hypothesis in two experiments, examining standardized neuropsychological working-memory tests in different social communication contexts. Our results show that the more ostensive communication context (eye contact, exaggerated intonation contours) impairs working-memory performance. These results draw attention to the fact that the communication style of the examiner could have a robust effect on working-memory performance and could even modify clinical diagnosis.
    • 2014
    • Chandra S. Sripada
    • Lag in maturation of the brain’s intrinsic functional architecture in attention-deficit/hyperactivity disorder
    • It was proposed that individuals with attention-deficit/hyperactivity disorder (ADHD) exhibit delays in brain maturation. In the last decade, resting state functional imaging has enabled detailed investigation of neural connectivity patterns and has revealed that the human brain is functionally organized into large-scale connectivity networks. In this study, we demonstrate that the developing relationships between default mode network (DMN) and task positive networks (TPNs) exhibit significant and specific maturational lag in ADHD. Previous research has found that individuals with ADHD exhibit abnormalities in DMN–TPN relationships. Our results provide strong initial evidence that these alterations arise from delays in typical maturational patterns. Our results invite further investigation into the neurobiological mechanisms in ADHD that produce delays in development of large-scale networks.
    • 2014
    • Sadegh Nabavi, Rocky Fox, Christophe D. Proulx, John Y. Lin, Roger Y. Tsien, Roberto Malinow
    • Engineering a memory with LTD and LTP
    • It has been proposed that memories are encoded by modification of synaptic strengths through cellular mechanisms such as long-term potentiation (LTP) and long-term depression (LTD)1. However, the causal link between these synaptic processes and memory has been difficult to demonstrate2. Here we show that fear conditioning3, 4, 5, 6, 7, 8, a type of associative memory, can be inactivated and reactivated by LTD and LTP, respectively. We began by conditioning an animal to associate a foot shock with optogenetic stimulation of auditory inputs targeting the amygdala, a brain region known to be essential for fear conditioning3, 4, 5, 6, 7, 8. Subsequent optogenetic delivery of LTD conditioning to the auditory input inactivates memory of the shock. Then subsequent optogenetic delivery of LTP conditioning to the auditory input reactivates memory of the shock. Thus, we have engineered inactivation and reactivation of a memory using LTD and LTP, supporting a causal link between these synaptic ..
    • 2009
    • Van Overwalle F
    • Understanding others' actions and goals by mirror and mentalizing systems: a meta-analysis.
    • This meta-analysis explores the role of the mirror and mentalizing systems in the understanding of other people's action goals. Based on over 200 fMRI studies, this analysis demonstrates that the mirror system - consisting of the anterior intraparietal sulcus and the premotor cortex - is engaged when one perceives articulated motions of body parts irrespective of their sensory (visual or auditory) or verbal format as well as when the perceiver executes them. This confirms the matching role of the mirror system in understanding biological action. Observation of whole-body motions and gaze engage the posterior superior temporal sulcus and most likely reflects an orientation response in line with the action or attention of the observed actor. In contrast, the mentalizing system - consisting of the temporo-parietal junction, the medial prefrontal cortex and the precuneus - is activated when behavior that enables inferences to be made about goals, beliefs or moral issues is presented in a..
    • 2008
    • Yu Yong Choi
    • Multiple Bases of Human Intelligence Revealed by Cortical Thickness and Neural Activation
    • We hypothesized that individual differences in intelligence (Spearman's g) are supported by multiple brain regions, and in particular that fluid (gF) and crystallized (gC) components of intelligence are related to brain function and structure with a distinct profile of association across brain regions. In 225 healthy young adults scanned with structural and functional magnetic resonance imaging sequences, regions of interest (ROIs) were defined on the basis of a correlation between g and either brain structure or brain function. In these ROIs, gC was more strongly related to structure (cortical thickness) than function, whereas gF was more strongly related to function (blood oxygenation level-dependent signal during reasoning) than structure. We further validated this finding by generating a neurometric prediction model of intelligence quotient (IQ) that explained 50% of variance in IQ in an independent sample. The data compel a nuanced view of the neurobiology of intelligence, provi..