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BackgroundCognitive impairments are a core feature in schizophrenia and are linked to poor social functioning. Numerous studies have shown that cognitive remediation can enhance cognitive and functional abilities in patients with this pathology. The underlying mechanism of these behavioral improvements seems to be related to structural and functional changes in the brain. However, studies on neural correlates of such enhancement remain scarce.ObjectivesWe explored the neural correlates of cognitive enhancement following cognitive remediation interventions in schizophrenia and the differential effect between cognitive training and other therapeutic interventions or patients’ usual care.MethodWe searched MEDLINE, PsycInfo, and ScienceDirect databases for studies on cognitive remediation therapy in schizophrenia that used neuroimaging techniques and a randomized design. Search terms included randomized controlled trial, cognitive remediation, cognitive training, rehabilitation, magnetic resonance imaging, positron emission tomography, electroencephalography, magnetoencephalography, near infrared spectroscopy, and diffusion tensor imaging. We selected randomized controlled trials that proposed multiple sessions of cognitive training to adult patients with a schizophrenia spectrum disorder and assessed its efficacy with imaging techniques.ResultsIn total, 15 reports involving 19 studies were included in the systematic review. They involved a total of 455 adult patients, 271 of whom received cognitive remediation. Cognitive remediation therapy seems to provide a neurobiological enhancing effect in schizophrenia. After therapy, increased activations are observed in various brain regions mainly in frontal – especially prefrontal – and also in occipital and anterior cingulate regions during working memory and executive tasks. Several studies provide evidence of an improved functional connectivity after cognitive training, suggesting a neuroplastic effect of therapy through mechanisms of functional reorganization. Neurocognitive and social-cognitive training may have a cumulative effect on neural networks involved in social cognition. The variety of proposed programs, imaging tasks, and techniques may explain the heterogeneity of observed neural improvements. Future studies would need to specify the effect of cognitive training depending on those variables.

Background: Emotional memory is an adaptive process that improves the memorization of emotional events or stimuli. In Post-Traumatic Stress Disorder (PTSD), emotional memory may be altered, which in turn may affect symptoms. Having a clearer view of the processes of interaction between memory and emotional stimuli in PTSD may improve our knowledge of this disorder, and could create new therapeutic management tools. Thus, we performed a systematic review of the evidence of specific emotional memory in PTSD patients.Method: Following PRISMA guidelines, a systematic review of MEDLINE, PsycInfo, and ScienceDirect was undertaken to identify controlled studies on emotional memory that used cognitive tasks on PTSD patients. The initial research was conducted from June 2017 to July 2017, and search terms included: Post-Traumatic Stress Disorder; PTSD; emotional memory; emotion; emotional; memory; and episodic memory.Results: Eighteen studies reporting on 387 PTSD patients met the eligibility criteria. Among the studies selected, 11 observed specific memory processing in PTSD patients, such as a greater memorization of negative information, or a trend to false recognition of negative information. In addition, attentional and inhibition processing seem to play an important role in emotional memory in PTSD sufferers. Furthermore, other studies that did not find behavioral differences between PTSD and control groups nevertheless showed differences in both specific cerebral activities and neurohormone levels during emotional memory tasks.Conclusion: This review has several limitations, including a limited number of controlled studies, small sample sizes, different tasks and methods. Nevertheless, the results of this systematic review provide interesting information on emotional memory for clinicians and researchers, as they seem to highlight facilitated memory processing for negative information in PTSD patients. This topic needs further controlled studies with sensitive behavioral tasks. Also, future studies may evaluate emotional memory after symptom amelioration.

<b><i>Background:</i></b> Executive functions (EF) are often impaired in autism spectrum disorder (ASD). Such dysfunctions are associated with anxiety, depression, and a lack of autonomy. Transcranial direct current stimulation (tDCS) has been shown to enhance EF in healthy adults and clinical populations and to improve working memory − a component of the EF − in adults with high-functioning ASD (HF-ASD). We hypothesized that tDCS could improve the EF of HF-ASD patients. Such enhancement could improve their adaptive behaviors. <b><i>Method:</i></b> Eight patients with HF-ASD received 10 consecutive cathodal tDCS sessions (2 mA) over the left dorsolateral prefrontal cortex (F3) for 15 min each in an open trial. EF (with the Stroop test, Trail Making Test [TMT] A and B, Modified Wisconsin Card Sorting Test [mWCST], and Verbal Fluency Test) and behavioral dysexecutive syndrome (with the Behavioral Dysexecutive Syndrome Inventory and the Repetitive and Restricted Behaviour scale) were assessed before and 10 days after treatment. <b><i>Results:</i></b> This study showed significant improvement in initiation (TMT-A time: <i>p</i> = 0.018) and cognitive flexibility (TMT-B time: <i>p</i> = 0.009; letter Verbal Fluency Test: <i>p</i> = 0.017; mWCST total errors: <i>p</i> = 0.028) after tDCS. Regarding behavior, the hypoactivity of the patients improved, as well as their repetitive and restrictive behaviors. In addition, this noninvasive neurostimulation technique was well tolerated. <b><i>Conclusions:</i></b> Flexibility and initiation are the most impaired EF in autism. These are promising results which justify a randomized and placebo-controlled study in a wider population. If these results were confirmed by a randomized controlled trial, tDCS could be an easy and well-tolerated adjunctive treatment aiming to improve the quality of life and the autonomy of ASD patients.