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Although cardiorespiratory exercise is known to affect cortical excitatory and inhibitory activity, the neurochemical mechanisms driving this effect are poorly understood. Animal models of Parkinson's disease identify dopamine D2 receptor expression as a candidate mechanism, but the link between the D2 receptor and exercise-induced changes in cortical activity in humans is unknown. Here, we examined the effect of a selective dopamine D2 receptor antagonist, sulpiride, on exercise-induced changes in cortical activity. We acquired measures of excitatory and inhibitory activity of the primary motor cortex using transcranial magnetic stimulation (TMS) from 23 healthy adults, both before and after a 20-min bout of high-intensity interval cycling exercise. We examined the effect of D2 receptor blockade (800 mg sulpiride) on these measures within a randomised, double-blind, placebo-controlled crossover design. Sulpiride abolished exercise-induced modulation of the cortical excitation:inhibition balance relative to placebo (P < 0.001, Cohen's d = 1.76). Sulpiride blocked both the increase in glutamatergic excitation and reduction in gamma-aminobutyric acid (GABA) inhibition that was observed following exercise in the placebo condition. Our results provide causal evidence that D2 receptor blockade eliminates exercise-induced changes in excitatory and inhibitory cortical networks, and have implications for how exercise should be prescribed in diseases of dopaminergic dysfunction. [Display omitted] • Sulpiride abolished exercise-induced modulation of excitation:inhibition balance. • Sulpiride blocked increase in excitation and reduction in inhibition post-exercise. • Causal evidence that D2 blockade eliminates exercise-induced changes in cortical activity. [ABSTRACT FROM AUTHOR]

Abstract: Haemorrhagic strokes are relatively less common compared to ischaemic strokes, with the vast majority of haemorrhages being intracerebral as opposed to subarachnoid. The definitive diagnosis of a haemorrhagic stroke is based on non-contrast CT imaging of the brain. Acute care should focus on prompt identification of the cause, minimizing the risk of haemorrhage expansion by controlling blood pressure and correcting any underlying coagulopathy, and obliterating vascular lesions with a high risk of rebleeding. Patients should be closely monitored, and emergent surgery should be considered in those patients who display signs of clinical deterioration, especially in the presence of posterior fossa haemorrhages. Future directions include refining the use of bedside neuro-monitoring and neuro-imaging techniques as well as developing novel approaches to minimize the complications of haemorrhagic stroke. [Copyright &y& Elsevier]

Abstract: Substantial evidence suggests that observed actions can engage their corresponding motor representations within the observer. It is currently believed that this process of observation–execution matching occurs relatively automatically, without the need for top-down control. In this study we tested the susceptibility of the observation–execution matching process to selective attention. We used a Go/NoGo paradigm to investigate the phenomenon of ‘automatic imitation’, in which participants are faster to initiate a hand movement that is congruent with a concurrently observed action, relative to one that is incongruent. First, we replicated previous findings of automatic imitation, and excluded the possibility that spatial compatibility effects might explain these results (Experiment 1). We then presented participants with the same goal-directed actions while directing their attention to an imperative stimulus that spatially overlapped, but was distinct from, the observed actions (Experiment 2). Crucially, automatic imitation no longer occurred when participants directed their attention away from the displayed actions and towards the spatially overlapping stimulus. In a final experiment, we examined whether the automatic imitation of grasp persists when participants attend to an irrelevant feature of the observed action, such as whether it is performed by a left or right hand (Experiment 3). Here we found that automatic imitation is contingent on participants attending to the feature of the observed hand that was relevant to their responses. Together these findings demonstrate the importance of selective mechanisms in the filtering of task-irrelevant actions, and indicate a role for top-down control in limiting the motoric simulation of observed actions. [Copyright &y& Elsevier]

Abstract: The adage that ‘Time is Brain’ remains a cornerstone of acute stroke treatment, and reflects the importance of timely diagnosis and treatment in order to minimise long-term consequences. The greatest advance in the management of ischaemic stroke has come in the form of reperfusion strategies, the success of which relies upon appropriate patient selection and the prompt initiation of therapy. The benefits of intravenous thrombolysis up to 4.5 hours are now firmly established, with trials underway to determine whether certain subgroups may benefit from thrombolysis beyond this timeframe. Intra-arterial thrombolysis has been used for decades but data on its efficacy and safety are limited. Novel methods of reperfusion, such as mechanical clot retrieval and stenting, have high recanalisation rates with acceptable safety and should be considered in patients with mid- to large-sized artery occlusion. Multi-modal reperfusion therapies, which use a combination of pharmacological and endovascular techniques, are showing encouraging results. [Copyright &y& Elsevier]

• fMRI meta-analysis used to identify neural correlates of effort-based valuation. • vmPFC activity scales positively with net value and negatively with effort costs. • pre-SMA ROI has an opposite pattern of activation. • vmPFC is a candidate region for domain-general cost/benefit value integration. Choosing how much effort to expend is critical for everyday decisions. While several neuroimaging studies have examined effort-based decision-making, results have been highly heterogeneous, leaving unclear which brain regions process effort-related costs and integrate them with rewards. We conducted two meta-analyses of functional magnetic resonance imaging data to examine consistent neural correlates of effort demands (23 studies, 15 maps, 549 participants) and net value (15 studies, 11 maps, 428 participants). The pre-supplementary motor area (pre-SMA) scaled positively with pure effort demand, whereas the ventromedial prefrontal cortex (vmPFC) showed the opposite effect. Moreover, regions that have been previously implicated in value integration in other cost domains, such as the vmPFC and ventral striatum, were consistently involved in signaling net value. The opposite response patterns of the pre-SMA and vmPFC imply that they are differentially involved in the representation of effort costs and value integration. These findings provide conclusive evidence that the vmPFC is a central node for net value computation and reveal potential brain targets to treat motivation-related disorders. [ABSTRACT FROM AUTHOR]

Binge-Eating Disorder (BED) involves anticipatory craving and urges, subjective loss-of-control during binge-eating episodes, and post-feeding psychological distress and guilt. Evidence indicates neurocognitive dysfunctions contribute to BED onset, maintenance, and treatment response. However, an integrated understanding of how cognitive processes underpin BED symptomology is lacking. We utilised a multi-stage decision-making model defining ten cognitive processes underpinning Preference Formation, Choice Implementation, Feedback Processing, and Flexibility/Shifting, to comprehensively review research published since 2013. We used preregistered PICOS criteria to assess 1966 articles identified from PubMed, PsycInfo, and Scopus database searches. This yielded 50 studies reporting behavioural cognitive tasks outcomes, comparing individuals with BED to controls with normal and higher weight. Meta-analyses revealed a unique profile of cognitive dysfunctions that spanned all decision-making stages. Significant deficits were evident in Uncertainty Evaluation, Attentional Inhibition, Choice Consistency, and Cognitive Flexibility/Set-shifting. We propose a novel model of dysfunctional decision-making processes in BED and describe their role in binge-eating behaviour. We further highlight the potential for cognitive interventions to target these processes and address the significant treatment gap in BED. • We meta-analysed BED cognitive dysfunctions via multi-stage decision-making theory. • People with BED show deficits relating to uncertainty, inhibition, consistency & flexibility. • Food-related contexts increase disinhibition; BMI moderates flexibility/shifting. • Findings can explain maladaptive eating choices & inform treatment targets. [ABSTRACT FROM AUTHOR]