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Response Selection (response + selection)
Selected AbstractsScript-driven imagery of self-injurious behavior in patients with borderline personality disorder: a pilot FMRI studyACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2010A. Kraus Objective:, Self-injurious behavior (SIB) is one of the most distinctive features of borderline personality disorder (BPD) and related to impulsivity and emotional dysregulation. Method:, Female patients with BPD (n = 11) and healthy controls (n = 10) underwent functional magnetic resonance imaging while listening to a standardized script describing an act of self-injury. Experimental sections of the script were contrasted to the neutral baseline section and group-specific brain activities were compared. Results:, While imagining the reactions to a situation triggering SIB, patients with BPD showed significantly less activation in the orbitofrontal cortex compared with controls. Furthermore, only patients with BPD showed increased activity in the dorsolateral prefrontal cortex during this section and a decrease in the mid-cingulate while imagining the self-injurious act itself. Conclusion:, This pattern of activation preliminary suggests an association with diminished emotion regulation, impulse control as well as with response selection and reappraisal during the imagination of SIB. [source] Preference judgements involve a network of structures within frontal, cingulate and insula corticesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2009Amir M. Chaudhry Abstract Environmental stimuli constantly compete for human attention and in many cases decisions are made based on the affective meaning they convey. Although the network of structures involved in processing affective value has been well described, the specific contribution of these structures to the process by which affective value guides decision making is less well understood and is the focus of the present study. Thus, subjects read descriptions of individually tailored holidays, varying in incentive value and then made preference judgements, cognitive judgements or no decision. Choices made from an affective perspective, compared with those made from a cognitive perspective, activated a region of the anterior insula/operculum and also the anterior cingulate cortex. Furthermore, activity in perigenual, anterior cingulate cortex was correlated with subjective ratings of incentive value. In contrast, medial orbitofrontal cortex (OFC) and a region of posterior ventrolateral prefrontal cortex (PFC), bordering on the insula, were found to be more active when affective stimuli guided response selection than when no selection was made. However, only the activity in the ventrolateral PFC was specific to response selection based on affective compared with cognitive judgements. It is proposed that the necessary introspection required to make subjective preference judgements is provided by the insula and cingulate cortices, while the medial OFC and posterior ventrolateral PFC/insula cortices contribute to stimulus evaluation and motivational aspects of response selection, respectively. [source] Functional specificity of human premotor,motor cortical interactions during action selectionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Jacinta O'Shea Abstract Functional connections between dorsal premotor cortex (PMd) and primary motor cortex (M1) have been revealed by paired-pulse transcranial magnetic stimulation (TMS). We tested if such connections would be modulated during a cognitive process (response selection) known to rely on those circuits. PMd,M1 TMS applied 75 ms after a cue to select a manual response facilitated motor-evoked potentials (MEPs). MEPs were facilitated at 50 ms in a control task of response execution, suggesting that PMd,M1 interactions at 75 ms are functionally specific to the process of response selection. At 100 ms, PMd,M1 TMS delayed choice reaction time (RT). Importantly, the MEP (at 75 ms) and the RT (at 100 ms) effects were correlated in a way that was hand-specific. When the response was made with the M1-contralateral hand, MEPs correlated with slower RTs. When the response was made with the M1-ipsilateral hand, MEPs correlated with faster RTs. Paired-pulse TMS confined to M1 did not produce these effects, confirming the causal influence of PMd inputs. This study shows that a response selection signal evolves in PMd early during the reaction period (75,100 ms), impacts on M1 and affects behaviour. Such interactions are temporally, anatomically and functionally specific, and have a causal role in choosing which movement to make. [source] The role of the medial caudate nucleus, but not the hippocampus, in a matching-to sample task for a motor responseEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2006Raymond P. Kesner Abstract A delayed-match-to-sample task was used to assess memory for motor responses in rats with control, hippocampus, or medial caudate nucleus (MCN) lesions. All testing was conducted on a cheeseboard maze in complete darkness using an infrared camera. A start box was positioned in the centre of the maze facing a randomly determined direction on each trial. On the sample phase, a phosphorescent object was randomly positioned to cover a baited food well in one of five equally spaced positions around the circumference of the maze forming a 180-degree arc 60 cm from the box. The rat had to displace the object to receive food and return to the start box. The box was then rotated to face a different direction. An identical baited phosphorescent object was placed in the same position relative to the start box. A second identical object was positioned to cover a different unbaited well. On the choice phase, the rat must remember the motor response made on the sample phase and make the same motor response on the choice phase to receive a reward. Hippocampus lesioned and control rats improved as a function of increased angle separation used to separate the correct object from the foil (45, 90, 135, and 180 degrees) and matched the performance of controls. However, rats with MCN lesions were impaired across all separations. Results suggest that the MCN, but not the hippocampus, supports working memory and/or a process aimed at reducing interference for motor response selection based on vector angle information. [source] Changes of effective connectivity between the lateral and medial parts of the prefrontal cortex during a visual taskEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2003Thierry Chaminade Abstract Structural equation modelling was used to study the change of connectivity during a visual task with continuous variation of the attention load. The model was based on areas defined by the haemodynamic responses described elsewhere [Mazoyer, P., Wicker, B. & Fonlupt, P. (2002) A neural network elicited by parametric manipulation of the attention load. Neuroreport, 13, 2331,2334], including occipitotemporal, parietal, temporal and prefrontal (lateral and medial areas) cortices. We have studied stationary- (which does not depend on the attentional load) and attention-related coupling between areas. This allowed the segregation of two subsystems. The first could reflect a system performing the integration step of the visual signal and the second a system participating in response selection. The major finding is the mutual negative influence between the lateral and medial parts of the prefrontal cortex. This negative influence between these two brain regions increased with the attention load. This is interpreted as a modification of the balance between integration and decision processes that are needed for the task to be efficiently completed. [source] Two systems of resting state connectivity between the insula and cingulate cortexHUMAN BRAIN MAPPING, Issue 9 2009Keri S. Taylor Abstract The insula and cingulate cortices are implicated in emotional, homeostatic/allostatic, sensorimotor, and cognitive functions. Non-human primates have specific anatomical connections between sub-divisions of the insula and cingulate. Specifically, the anterior insula projects to the pregenual anterior cingulate cortex (pACC) and the anterior and posterior mid-cingulate cortex (aMCC and pMCC); the mid-posterior insula only projects to the posterior MCC (pMCC). In humans, functional neuroimaging studies implicate the anterior insula and pre/subgenual ACC in emotional processes, the mid-posterior insula with awareness and interoception, and the MCC with environmental monitoring, response selection, and skeletomotor body orientation. Here, we tested the hypothesis that distinct resting state functional connectivity could be identified between (1) the anterior insula and pACC/aMCC; and (2) the entire insula (anterior, middle, and posterior insula) and the pMCC. Functional connectivity was assessed from resting state fMRI scans in 19 healthy volunteers using seed regions of interest in the anterior, middle, and posterior insula. Highly correlated, low-frequency oscillations (< 0.05 Hz) were identified between specific insula and cingulate subdivisions. The anterior insula was shown to be functionally connected with the pACC/aMCC and the pMCC, while the mid/posterior insula was only connected with the pMCC. These data provide evidence for a resting state anterior insula,pACC/aMCC cingulate system that may integrate interoceptive information with emotional salience to form a subjective representation of the body; and another system that includes the entire insula and MCC, likely involved in environmental monitoring, response selection, and skeletomotor body orientation. Human Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source] Cognitive processes facilitated by contextual cueing: Evidence from event-related brain potentialsPSYCHOPHYSIOLOGY, Issue 3 2009Andrea Schankin Abstract Finding a target in repeated search displays is faster than finding the same target in novel ones (contextual cueing). It is assumed that the visual context (the arrangement of the distracting objects) is used to guide attention efficiently to the target location. Alternatively, other factors, e.g., facilitation in early visual processing or in response selection, may play a role as well. In a contextual cueing experiment, participant's electrophysiological brain activity was recorded. Participants identified the target faster and more accurately in repeatedly presented displays. In this condition, the N2pc, a component reflecting the allocation of visual-spatial attention, was enhanced, indicating that attention was allocated more efficiently to those targets. However, also response-related processes, reflected by the LRP, were facilitated, indicating that guidance of attention cannot account for the entire contextual cueing benefit. [source] Saccade generation and suppression in schizophrenia: Effects of response switching and perseverationPSYCHOPHYSIOLOGY, Issue 5 2008Cosima Franke Abstract Poor antisaccade performance is a reliable index of action control deficits in schizophrenia. To further elucidate the underlying cognitive impairments, the current study aimed to confirm effects of switching the response direction on saccadic performance and to investigate whether response switch effects relate to perseveration. Fourteen schizophrenia patients and 14 healthy controls performed sequences of 1 to 3 simple volitional saccades to one direction and a subsequent volitional saccade with distractor to the same or the opposite direction. Response switches increased error rates in schizophrenia if they followed 3 saccades to the opposite side, suggesting that response switching affects performance on conditions of strong persisting response programs. The increase of response switch error rates with multiple repetitions of the prior response points to a relationship between perseveration and response selection. [source] Parsing the late positive complex: Mental chronometry and the ERP components that inhabit the neighborhood of the P300PSYCHOPHYSIOLOGY, Issue 5 2004Joseph Dien Abstract Falkenstein, Hohnsbein, and Hoorman (1994) suggested that common measures of P300 latency confound a "P-SR" component whose latency corresponds to stimulus evaluation time and a "P-CR" component whose latency varies with response-selection time, thus casting doubt on work in mental chronometry that relies on P300 latency. We report here a replication and extension of Falkenstein et al. (1994) using a high-density 129-electrode montage with 11 subjects. Spatiotemporal PCA was used to extract the components of the ERP. A centroid measure is also introduced for detecting waveform-timing changes beyond just peak latency. In terms of componentry, we argue that the P-SR and the P-CR, correspond to the P3a/Novelty P3 and the P300, respectively. Conceptually, we dispute the proposed distinction between stimulus evaluation and response selection. We suggest a four-stage ERP model of information processing and place the P3a and the P300 in this framework. [source] Mental rotation delays the heart beat: Probing the central processing bottleneckPSYCHOPHYSIOLOGY, Issue 5 2003J. Richard Jennings Abstract We tested the hypothesis that mental rotation would delay response-related processing as indicated by transient slowing of the heart beat. Thirty college-age subjects (half female) were presented with normal and mirror image letters rotated at 0, 60, 120, and 180°. Three letters were assigned to a right-hand response; a separate three to a left-hand response. Responses were only required for letters in one orientation, mirror or normal. Continuous measures of interbeat interval (IBI) of the heart, respiration, and muscle tension were collected. Performance results were largely consistent with prior findings. Greater angular displacement of the stimuli was associated with greater lengthening of IBI immediately after the stimulus. IBI was influenced equally by angle of rotation in respond and inhibit trials. The lengthening of IBI was interpreted as due to a delay in response selection and execution due to mental rotation. [source] | ||||||||||