Article

The Reorienting System of the Human Brain: From Environment to Theory of Mind

Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
Neuron (Impact Factor: 15.05). 06/2008; 58(3):306-24. DOI: 10.1016/j.neuron.2008.04.017
Source: PubMed

ABSTRACT

Survival can depend on the ability to change a current course of action to respond to potentially advantageous or threatening stimuli. This "reorienting" response involves the coordinated action of a right hemisphere dominant ventral frontoparietal network that interrupts and resets ongoing activity and a dorsal frontoparietal network specialized for selecting and linking stimuli and responses. At rest, each network is distinct and internally correlated, but when attention is focused, the ventral network is suppressed to prevent reorienting to distracting events. These different patterns of recruitment may reflect inputs to the ventral attention network from the locus coeruleus/norepinephrine system. While originally conceptualized as a system for redirecting attention from one object to another, recent evidence suggests a more general role in switching between networks, which may explain recent evidence of its involvement in functions such as social cognition.

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Available from: Gaurav H Patel, May 15, 2014
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    • "The projection from the FC and ACC to the LC is believed to contribute to the reconsolidation of memory processes (Sara 2000Sara , 2009Sara , 2010). The FC regulates the control of attention to a novel or salient stimulus (Corbetta et al. 2008; Robbins and Arnsten 2009). According to the integrative theory of NA-LC function, the OFC and ACC send projections to the LC, driving transitions between the LC modes and phasic LC responses to adapt synaptic gain (Aston-Jones and Cohen 2005). "
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    Preview · Article · Jan 2016 · Cerebral Cortex
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    • "Notably, rTPJ engagement is far from restricted to the domain of social cognition. Thanks to its strong connectivity with prefrontal and posterior parietal structures [22] [25], many functions are associated with this area and three of them seem of particular relevance for the present discussion: rTPJ has been associated with attentional reorienting to salient or task-relevant events [26], it may be engaged in the comparison of internal expectations with external events [20] [27], and it seems to allow a " rich " , multimodal representation of the social context [25]. We propose that the combination of these three functions is what underpins Self-Other distinction. "
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    ABSTRACT: Neuroscientific research has identified two fundamental components of empathy: shared emotional representations between self and other, and self-other distinction. The concept of shared representations suggests that during empathy, we co-represent another person’s affect by engaging brain and bodily functions underpinning the first-hand experience of the emotion we are empathizing with. This possible grounding of empathy in our own emotional experiences explains the necessity for self-other distinction, which is the capacity to correctly distinguish between our own affective representations and those related to the other. In spite of the importance of these two components in empathy, several aspects still remain controversial. This paper addresses some of them and focuses on (i) the distinction between shared activations versus representations, raising the question what shared representations entail in terms of the underlying neural mechanisms, (ii) the possible mechanisms behind self-other distinction in the cognitive and the affective domains, and whether they have distinct neural underpinnings and (iii) the consequences associated with a selective impairment of one of the two components, thereby addressing their importance in mental disorders such as autism spectrum disorders, psychopathy and alexithymia. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
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    • "On the other hand, explicit attention studies usually reveal the activation of distinct neural structures which are thought to regulate selective attention processes. Specifically, the regulation of attention has been associated with activity in frontal cortical regions, including frontal and supplementary eye fields as well as the dorso-lateral prefrontal cortex accompanied by regions of the superior and inferior parietal lobe (Desimone and Duncan, 1995; Kastner and Ungerleider, 2000; Corbetta et al., 2008). In sum, while implicit emotional and explicit task-related attention processes share common neural substrates such as enhanced sensory-perceptual processing, they are also characterized by distinct activations in limbic brain areas implicated in emotion processing and prefrontal regions associated with the volitional regulation of selective attention, respectively. "
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