19 research outputs found

    Assessing the impact of emotion in dual pathway models of sensory processing.

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    In our daily environment, we are constantly encountering an endless stream of information which we must be able to sort and prioritize. Some of the features that influence this are the emotional nature of stimuli and the emotional context of events. Emotional information is often given preferential access to neurocognitive resources, including within sensory processing systems. Interestingly, both auditory and visual systems are divided into dual processing streams; a ventral object identity/perception stream and a dorsal object location/action stream. While effects of emotion on the ventral streams are relatively well defined, its effect on dorsal stream processes remains unclear. The present thesis aimed to investigate the impact of emotion on sensory systems within a dual pathway framework of sensory processing. Study I investigated the role of emotion during auditory localization. While undergoing fMRI, participants indicated the location of an emotional or non-emotional sound within an auditory virtual environment. This revealed that the neurocognitive structures displaying activation modulated by emotion were not the same as those modulated by sound location. Emotion was represented in regions associated with the putative auditory ‘what’ but not ‘where’ stream. Study II examined the impact of emotion on ostensibly similar localization behaviours mediated differentially by the dorsal versus ventral visual processing stream. Ventrally-mediated behaviours were demonstrated to be impacted by the emotional context of a trial, while dorsally-mediated behaviours were not. For Study III, a motion-aftereffect paradigm was used to investigate the impact of emotion on visual area V5/MT+. This area, traditionally believed to be involved in dorsal stream processing, has a number of characteristics similar to a ventral stream structure. It was discovered that V5/MT+ activity was modulated both by presence of perceptual motion and emotional content of an image. In addition, this region displayed patterns of functional connectivity with the amygdala that were significantly modulated by emotion. Together, these results suggest that emotional information modulates neural processing within ventral sensory processing streams, but not dorsal processing streams. These findings are discussed with respect to current models of emotional and sensory processing, including amygdala connections to sensory cortices and emotional effects on cognition and behaviour

    Experiential History as a Tuning Parameter for Attention

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    [Peer commentary on “Visual selection: usually fast and automatic; seldom slow and volitional,” by J. Theeuwes]. 'Journal of Cognition'. In his current opinion piece, Theeuwes emphasizes the role of selection history as a third source of attentional selection, beyond top-down and bottom-up mechanisms, thus challenging traditional dual-process models of attention. While we agree that selection history impacts the allocation of attention, our own work suggests that this terminology may be too restrictive, and propose the simple term 'history' as a better reflection of the impact of learning on our selection biases. Furthermore, we propose that the role of selection/experiential history on attention may not be as a unique third source of attentional selection, but rather as a tuning parameter, allowing certain categories of item to be endowed with greater task-based or feature-driven salience in a context and history dependent manner. This conceptualization presents an alternative to abandoning dual-process models of attention altogether. Rather, we can reimagine how task-based and feature-driven processes may be controlled by past experience in a dynamic and adaptable system

    Neural effects of oxytocin and mimicry in frontotemporal dementia: A randomized crossover study

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    OBJECTIVE: To determine whether intranasal oxytocin, alone or in combination with instructed mimicry of facial expressions, would augment neural activity in patients with frontotemporal dementia (FTD) in brain regions associated with empathy, emotion processing, and the simulation network, as indexed by blood oxygen-level dependent (BOLD) signal during fMRI. METHODS: In a placebo-controlled, randomized crossover design, 28 patients with FTD received 72 IU intranasal oxytocin or placebo and then completed an fMRI facial expression mimicry task. RESULTS: Oxytocin alone and in combination with instructed mimicry increased activity in regions of the simulation network and in limbic regions associated with emotional expression processing. CONCLUSIONS: The findings demonstrate latent capacity to augment neural activity in affected limbic and other frontal and temporal regions during social cognition in patients with FTD, and support the promise and need for further investigation of these interventions as therapeutics in FTD. CLINICALTRIALSGOV IDENTIFIER: NCT01937013. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that a single dose of 72 IU intranasal oxytocin augments BOLD signal in patients with FTD during viewing of emotional facial expressions

    Assessing the efficacy of tablet-based simulations for learning pseudo-surgical instrumentation.

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    Nurses and surgeons must identify and handle specialized instruments with high temporal and spatial precision. It is crucial that they are trained effectively. Traditional training methods include supervised practices and text-based study, which may expose patients to undue risk during practice procedures and lack motor/haptic training respectively. Tablet-based simulations have been proposed to mediate some of these limitations. We implemented a learning task that simulates surgical instrumentation nomenclature encountered by novice perioperative nurses. Learning was assessed following training in three distinct conditions: tablet-based simulations, text-based study, and real-world practice. Immediately following a 30-minute training period, instrument identification was performed with comparable accuracy and response times following tablet-based versus text-based training, with both being inferior to real-world practice. Following a week without practice, response times were equivalent between real-world and tablet-based practice. While tablet-based training does not achieve equivalent results in instrument identification accuracy as real-world practice, more practice repetitions in simulated environments may help reduce performance decline. This project has established a technological framework to assess how we can implement simulated educational environments in a maximally beneficial manner

    Assessing the efficacy of tablet-based simulations for learning pseudo-surgical instrumentation : [supplementary material]

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    A publication based on this data is under review at PLOS-ONE.Arts, Faculty ofNon UBCPsychology, Department ofUnreviewedFacultyPostdoctora

    Decoding auditory spatial and emotional information encoding using multivariate versus univariate techniques

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    Emotion can have diverse effects on behaviour and perception, modulating function in some circumstances, and sometimes having little effect. Recently, it was identified that part of the heterogeneity of emotional effects could be due to a dissociable representation of emotion in dual pathway models of sensory processing. Our previous fMRI experiment using traditional univariate analyses showed that emotion modulated processing in the auditory \u27what\u27 but not \u27where\u27 processing pathway. The current study aims to further investigate this dissociation using a more recently emerging multi-voxel pattern analysis searchlight approach. While undergoing fMRI, participants localized sounds of varying emotional content. A searchlight multi-voxel pattern analysis was conducted to identify activity patterns predictive of sound location and/or emotion. Relative to the prior univariate analysis, MVPA indicated larger overlapping spatial and emotional representations of sound within early secondary regions associated with auditory localization. However, consistent with the univariate analysis, these two dimensions were increasingly segregated in late secondary and tertiary regions of the auditory processing streams. These results, while complimentary to our original univariate analyses, highlight the utility of multiple analytic approaches for neuroimaging, particularly for neural processes with known representations dependent on population coding

    Guiding Low Spatial Ability Individuals through Visual Cueing: The Dual Importance of Where and When to Look

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    Research suggests that spatial ability may predict success in complex disciplines including anatomy, where mastery requires a firm understanding of the intricate relationships occurring along the course of veins, arteries, and nerves, as they traverse through and around bones, muscles, and organs. Debate exists on the malleability of spatial ability, and some suggest that spatial ability can be enhanced through training. It is hypothesized that spatial ability can be trained in low-performing individuals through visual guidance. To address this, training was completed through a visual guidance protocol. This protocol was based on eye-movement patterns of high-performing individuals, collected via eye-tracking as they completed an Electronic Mental Rotations Test (EMRT). The effects of guidance were evaluated using 33 individuals with low mental rotation ability, in a counterbalanced crossover design. Individuals were placed in one of two treatment groups (late or early guidance) and completed both a guided, and an unguided EMRT. A third group (no guidance/control) completed two unguided EMRTs. All groups demonstrated an increase in EMRT scores on their second test (P \u3c 0.001); however, an interaction was observed between treatment and test iteration (P = 0.024). The effect of guidance on scores was contingent on when the guidance was applied. When guidance was applied early, scores were significantly greater than expected (P = 0.028). These findings suggest that by guiding individuals with low mental rotation ability where to look early in training, better search approaches may be adopted, yielding improvements in spatial reasoning scores. It is proposed that visual guidance may be applied in spatial fields, such as STEMM (science, technology, engineering, mathematics and medicine), surgery, and anatomy to improve student\u27s interpretation of visual content. Anat Sci Educ. (c) 2018 American Association of Anatomists

    Crossmodal reorganization in the early deaf switches sensory, but not behavioral roles of auditory cortex

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    It is well known that early disruption of sensory input from one modality can induce crossmodal reorganization of a deprived cortical area, resulting in compensatory abilities in the remaining senses. Compensatory effects, however, occur in selected cortical regions and it is not known whether such compensatory phenomena have any relation to the original function of the reorganized area. In the cortex of hearing cats, the auditory field of the anterior ectosylvian sulcus (FAES) is largely responsive to acoustic stimulation and its unilateral deactivation results in profound contralateral acoustic orienting deficits. Given these functional and behavioral roles, the FAES was studied in early-deafened cats to examine its crossmodal sensory properties as well as to assess the behavioral role of that reorganization. Recordings in the FAES of early-deafened adults revealed robust responses to visual stimulation as well as receptive fields that collectively represented the contralateral visual field. A second group of early-deafened cats was trained to localize visual targets in a perimetry array. In these animals, cooling loops were surgically placed on the FAES to reversibly deactivate the region, which resulted in substantial contralateral visual orienting deficits. These results demonstrate that crossmodal plasticity can substitute one sensory modality for another while maintaining the functional repertoire of the reorganized region
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