Numerous studies argue that cortical reorganization may contribute to the restoration of motor function following stroke. However, the evolution of changes during the post-stroke reorganization has been little studied. This study sought to identify dynamic changes in the functional organization, particularly topological characteristics, of the motor execution network during the stroke recovery process. Ten patients (nine male and one female) with subcortical infarctions were assessed by neurological examination and scanned with resting-state functional magnetic resonance imaging across five consecutive time points in a single year. The motor execution network of each subject was constructed using a functional connectivity matrix between 21 brain regions and subsequently analysed using graph theoretical approaches. Dynamic changes in topological configuration of the network during the process of recovery were evaluated by a mixed model. We found that the motor execution network gradually shifted towards a random mode during the recovery process, which suggests that a less optimized reorganization is involved in regaining function in the affected limbs. Significantly increased regional centralities within the network were observed in the ipsilesional primary motor area and contralesional cerebellum, whereas the ipsilesional cerebellum showed decreased regional centrality. Functional connectivity to these brain regions demonstrated consistent alterations over time. Notably, these measures correlated with different clinical variables, which provided support that the findings may reflect the adaptive reorganization of the motor execution network in stroke patients. In conclusion, the study expands our understanding of the spectrum of changes occurring in the brain after stroke and provides a new avenue for investigating lesion-induced network plasticity.

Objective. Several studies have provided evidence for the claim that a subgroup of (schizophrenic) patients with current delusions share a jumping to conclusions ( JTC) bias. The primary aim of the present study was to investigate whether currently deluded and non-deluded schizophrenic patients perform differently on three tasks tapping probabilistic reasoning. Method.Probabilistic reasoning was assessed in 31 schizophrenic patients, 28 psychiatric controls, and 17 healthy controls. In addition to the traditional draws to decision procedure, we employed two tasks for which participants had to judge, at each stage, the likelihood that beads come from either container (graded estimates procedure). Reaction times were recorded for the graded estimates procedure.Results. A JTC bias was displayed by 42% of the schizophrenic patients in the draws to decision condition, while 7% of the psychiatric patients and none of the healthy controls reached a decision after only one bead. A similar pattern of results was observed for the graded estimates procedure. This bias was more pronounced in deluded schizophrenic patients, although currently non-deluded patients also showed evidence for earlier decisions. A bias to over-adjust when confronted with potentially disconfirmatory evidence was confined to deluded schizophrenic participants. There was also evidence for an increase in JTC in the deluded group over the course of the tasks. No substantial group differences occurred with respect to reaction time parameters indicating that results are not attributable to impulsivity.Discussion. The findings provide further evidence for state and trait characteristics of abnormal reasoning in paranoid schizophrenia. Results are discussed in light of several competing explanations for JTC in schizophrenia.In 1986, Hemsley and Garety put forward the hypothesis that deluded patients may share abnormalities in logical inference. Specifically, a jumping to conclusions ( JTC)

While the majority of cognitive studies on auditory hallucinations (AHs) have been conducted in schizophrenia (SZ), an increasing number of researchers are turning their attention to different clinical and nonclinical populations, often using SZ findings as a model for research. Recent advances derived from SZ studies can therefore be utilized to make substantial progress on AH research in other groups. The objectives of this article were to (1) present an up-to-date review regarding the cognitive mechanisms of AHs in SZ, (2) review findings from cognitive research conducted in other clinical and nonclinical groups, and (3) integrate these recent findings into a cohesive framework. First, SZ studies show that the cognitive underpinnings of AHs include self-source-monitoring deficits and executive and inhibitory control dysfunctions as well as distortions in top-down mechanisms, perceptual and linguistic processes, and emotional factors. Second, consistent with SZ studies, findings in other population groups point to the role of top-down processing, abnormalities in executive inhibition, and negative emotions. Finally, we put forward an integrated model of AHs that incorporates the above findings. We suggest that AHs arise from an interaction between abnormal neural activation patterns that produce salient auditory signals and top-down mechanisms that include signal detection errors, executive and inhibition deficits, a tapestry of expectations and memories, and state characteristics that influence how these experiences are interpreted. Emotional factors play a particular prominent role at all levels of this hierarchy. Our model is distinctively powerful in explaining a range of phenomenological characteristics of AH across a spectrum of disorders.

The gap between our advanced understanding of cognitive processes in schizophrenia and its application in clinical treatment is increasingly being narrowed. Despite emerging evidence for the feasibility and efficacy of metacognitive training as a stand-alone program, its most powerful application may be in combination with individual cognitive-behavioral therapy.

The present article provides a narrative review of empirical studies on metacognitive training in psychosis (MCT). MCT represents an amalgam of cognitive-behavioral therapy (CBT), cognitive remediation (CRT) and psychoeducation. The intervention is available in either a group (MCT) or an individualized (MCT+) format. By sowing the seeds of doubt in a playful and entertaining fashion, the program targets positive symptoms, particularly delusions. It aims to raise patients' awareness for common cognitive traps or biases (e.g., jumping to conclusions, overconfidence in errors, bias against disconfirmatory evidence) that are implicated in the formation and maintenance of psychosis. The majority of studies confirm that MCT meets its core aim, the reduction of delusions. Problems (e.g., potential allegiance effects) and knowledge gaps (i.e., outcome predictors) are highlighted. The preliminary data suggest that the individual MCT format is especially effective in addressing symptoms, cognitive biases and insight. We conclude that MCT appears to be a worthwhile complement to pharmacotherapy.

Despite more than 2 decades of neuroimaging investigations, there is currently insufficient evidence to fully understand the neurobiological substrate of auditory hallucinations (AH). However, some progress has been made with imaging studies in patients with AH consistently reporting altered structure and function in speech and language, sensory, and nonsensory regions. This report provides an update of neuroimaging studies of AH with a particular emphasis on more recent anatomical, physiological, and neurochemical imaging studies. Specifically, we provide (1) a review of findings in schizophrenia and nonschizophrenia voice hearers, (2) a discussion regarding key issues that have interfered with progress, and (3) practical recommendations for future studies.

7Background: Previous schizophrenia research involving the "beads task" has suggested an association between delusions and 2 reasoning biases: (1) "jumping to conclusions" (JTC), whereby early, resolute decisions are formed on the basis of little evidence and (2) overadjustment of probability estimates following a single instance of disconfirmatory evidence. In the current study, we used a novel JTC-style paradigm to provide new information about a cognitive operation common to these 2 reasoning biases. Methods: Using a task that required participants to rate the likelihood that a fisherman was catching a series of black or white fish from Lake A and not Lake B, and vice versa, we compared the responses of 4 groups (healthy, bipolar, nondelusional schizophrenia and delusional schizophrenia) when we manipulated 2 elements of the Bayesian formula: incoming data and prior odds. Results: Regardless of our manipulations of the Bayesian formula, the delusional schizophrenia group gave significantly higher likelihood ratings for the lake that best matched the colour of the presented fish, but the ratings for the nonmatching lake did not differ from the other groups. Limitations: The limitations of this study include a small sample size for the group of severely delusional patients and a preponderance of men in the schizophrenia sample. Conclusion: Delusions in schizophrenia are associated with hypersalience of evidence-hypothesis matches but normal salience of nonmatches. When the colour of the incoming data is uniform (fish of only one colour), this manifests as JTC early in a series, and when the colour of incoming data varies (both black and white fish), this manifests as an overadjustment midseries. This account can provide a unifying explanation for delusion-associated performance patterns previously observed in the beads task in schizophrenia.

HighlightsThe language, auditory and memory/limbic networks are of particular relevance for auditory verbal hallucinations.An increased interaction among the auditory-language and striatal brain regions occurs while patients hallucinate.Fronto-temporal connections are often altered in AVH individuals, but there is no consensus regarding increase or decrease.Connections of the interhemispheric auditory pathway are stronger for first episode patients, but they are weaker in chronic patients.The majority of studies support hybrid AVH hypotheses in which all three networks and the striatal network are involved.