The Role of the Cognitive Control System in Recovery from Bilingual Aphasia: A Multiple Single-Case fMRI Study.

Aphasia in bilingual patients is a therapeutic challenge since both languages can be impacted by the same lesion. Language control has been suggested to play an important role in the recovery of first (L1) and second (L2) language in bilingual aphasia following stroke. To test this hypothesis, we collected behavioral measures of language production (general aphasia evaluation and picture naming) in each language and language control (linguistic and nonlinguistic switching tasks), as well as fMRI during a naming task at one and four months following stroke in five bilingual patients suffering from poststroke aphasia. We further applied dynamic causal modelling (DCM) analyses to the connections between language and control brain areas. Three patients showed parallel recovery in language production, one patient improved in L1, and one improved in L2 only. Language-control functions improved in two patients. Consistent with the dynamic view of language recovery, DCM analyses showed a higher connectedness between language and control areas in the language with the better recovery. Moreover, similar degrees of connectedness between language and control areas were found in the patients who recovered in both languages. Our data suggest that engagement of the interconnected language-control network is crucial in the recovery of languages.

Language specificity of lexical-phonological therapy in bilingual aphasia: A clinical and electrophysiological study.

Based on findings for overlapping representations of bilingual people's first (L1) and second (L2) languages, unilingual therapies of bilingual aphasia have been proposed to benefit the untrained language. However, the generalisation patterns of intra- and cross-language and phonological therapy and their neural bases remain unclear. We tested whether the effects of an intensive lexical-phonological training (LPT) in L2 transferred to L1 word production in a Persian-French bilingual stroke patient with Broca's aphasia. Language performance was assessed using the Bilingual Aphasia Test, a 144-item picture naming (PN) task and a word-picture verification (WPV) task. Electroencephalography (EEG) was recorded during PN and WPV in both languages before and after an LPT in French on a wordlist from the PN task. After the therapy, naming improved only for the treated L2 items. The naming performance improved neither in the untrained L2 items nor in the corresponding items in L1. EEG analyses revealed a Language x Session topographic interaction at 540 ms post-stimulus, driven by a modification of the electrophysiological response to the treated L2 but not L1 items. These results indicate that LPT modified the brain networks engaged in the phonological-phonetic processing during naming only in the trained language for the trained items.

Inter- and intrahemispheric dissociations in ideomotor apraxia: a large-scale lesion-symptom mapping study in subacute brain-damaged patients.

Pantomimes of object use require accurate representations of movements and a selection of the most task-relevant gestures. Prominent models of praxis, corroborated by functional neuroimaging studies, predict a critical role for left parietal cortices in pantomime and advance that these areas store representations of tool use. In contrast, lesion data points to the involvement of left inferior frontal areas, suggesting that defective selection of movement features is the cause of pantomime errors. We conducted a large-scale voxel-based lesion-symptom mapping analyses with configural/spatial (CS) and body-part-as-object (BPO) pantomime errors of 150 left and right brain-damaged patients. Our results confirm the left hemisphere dominance in pantomime. Both types of error were associated with damage to left inferior frontal regions in tumor and stroke patients. While CS pantomime errors were associated with left temporoparietal lesions in both stroke and tumor patients, these errors appeared less associated with parietal areas in stroke than in tumor patients and less associated with temporal in tumor than stroke patients. BPO errors were associated with left inferior frontal lesions in both tumor and stroke patients. Collectively, our results reveal a left intrahemispheric dissociation for various aspects of pantomime, but with an unspecific role for inferior frontal regions.

Is online self-regulatory training effective in weight control? A pilot experiment on adolescence obesity during coronavirus-19 lockdown.

OBJECTIVE: Studies have shown that obesity is associated with decreased executive function. Impaired executive functions lead to poor self-regulation, which in turn may result in persistence of unhealthy behaviors, including eating behaviors, throughout life. Increasing self-regulation in childhood and adolescence has positive effects on creating healthy behaviors such as reducing unnecessary eating and changing unhealthy eating habits. The main purpose of this study is to evaluate an intervention package based on cognitive self-regulation training in changing eating behaviors and reducing obesity in children and adolescents. METHODS: Fifty-six students with obesity aged 12-16 years participated in the study in three groups (cognitive self-regulation training [CSRT], diet, and control). The CSRT group received twenty 30-min online training sessions with a diet over 10 weeks. The diet group received only a diet with no other intervention, and the control group did not receive any intervention. RESULTS: The results of our 2 × 3 repeated-measures ANOVA showed that the CSRT group had a mean BMI decrease of 2.21 (kg/m2 ) after ten weeks, and 3.24 (kg/m2 ) at the follow-up time. The diet group had a BMI decrease of 0.49 (kg/m2 ) at the ten weeks. In addition, the results showed that the CSRT had a significant reduction in eating behaviors such as external eating and emotional eating. However, the other two groups showed no changes in eating behaviors. CONCLUSIONS: Our results show that online cognitive self-regulation training has been effective in weight loss and eating behaviors. This study shows promising evidence for the efficacy of the online CSRT-training as a weight stabilization intervention in children with obesity.

Language distance modulates cognitive control in bilinguals.

Linguistic processes in the bilingual brain are partially shared across languages, and the degree of neural overlap between the languages is influenced by several factors, including the age of acquisition, relative language proficiency, and immersion. There is limited evidence on the role of linguistic distance on the performance of the language control as well as domain-general cognitive control systems. The present study aims at exploring whether being bilingual in close and distant language pairs (CLP and DLP) influences language control and domain-general cognitive processes. We recruited two groups of DLP (Persian-English) and CLP (French-English) bilinguals. Subjects performed language nonswitching and switching picture-naming tasks and a nonlinguistic switching task while EEG data were recorded. Behaviorally, CLP bilinguals showed a lower cognitive cost than DLP bilinguals, reflected in faster reaction times both in language switching (compared to nonswitching) and nonlinguistic switching. ERPs showed differential involvement of cognitive control regions between the CLP and DLP groups during linguistic switching vs. nonswitching at 450 to 515 ms poststimulus presentation. Moreover, there was a difference between CLP and DLP groups from 40 to 150 ms in the nonlinguistic task. Our electrophysiological results confirm a stronger involvement of language control and domain-general cognitive control regions in CLP bilinguals.

rsfMRI based evidence for functional connectivity alterations in adults with developmental stuttering.

Persistent developmental stuttering (PDS) is defined as a speech disorder mainly characterized by intermittent involuntary disruption in normal fluency, time patterning, and rhythm of speech. Although extensive functional neuroimaging studies have explored brain activation alterations in stuttering, the main affected brain regions/networks in PDS still remain unclear. Here, using functional magnetic resonance imaging (fMRI), we investigated resting-state whole-brain functional connectivity of 15 adults who stutter (PDS group) and 15 age-matched control individuals to reveal the connectivity abnormalities associated with stuttering. We were also interested in exploring how the severity of stuttering varies across individuals to understand the compensatory mechanism of connectivity pattern in patients showing less symptoms. Our results revealed decreased connectivity of left frontal pole and left middle frontal gyrus (MidFG) with right precentral/postcentral gyrus in stuttering individuals compared with control participants, while less symptomatic PDS individuals showed greater functional connectivity between left MidFG and left caudate. Additionally, our finding indicated reduced connectivity in the PDS group between the left superior temporal gyrus (STG) and several brain regions including the right limbic lobe, right fusiform, and right cerebellum, as well as the left middle temporal gyrus (MTG). We also observed that PDS individuals with less severe symptoms had stronger connectivity between right MTG and several left hemispheric regions including inferior frontal gyrus (IFG) and STG. The connectivity between right fronto-orbital and right MTG was also negatively correlated with stuttering severity. These findings may suggest the involvement of right MTG and left MidFG in successful compensatory mechanisms in more fluent stutterers.

Behavioral and electrophysiological signatures of word translation processes.

Translation is a demanding process during which a message is analyzed, translated and communicated from one language to another. Despite numerous studies on translation mechanisms, the electrophysiological processes underlying translation with overt production remain largely unexplored. Here, we investigated how behavioral response patterns and spatial-temporal brain dynamics differ in a translation compared to a control within-language word-generation task. We also investigated how forward and backward translation differs on the behavioral and electrophysiological level. To address these questions, healthy late bilingual subjects performed a translation and a within-language control task while a 128-channel EEG was recorded. Behavioral data showed faster responses for translation compared to within-language word generation and faster responses for backward than forward translation. The ERP-analysis revealed stronger early ( < 200ms) preparatory and attentional processes for between than within word generation. Later (424-630ms) differences were characterized by distinct engagement of domain-general control networks, namely self-monitoring and lexical access interference. Language asymmetry effects occurred at a later stage (600ms), reflecting differences in conceptual processing characterized by a larger involvement of areas implicated in attention, arousal and awareness for forward versus backward translation.

Dorsolateral Prefrontal Transcranial Direct Current Stimulation Modulates Language Processing but Does Not Facilitate Overt Second Language Word Production.

Word retrieval in bilingual speakers partly depends on executive control systems in the left prefrontal cortex - including dorsolateral prefrontal cortex (DLPFC). We tested the hypothesis that DLPFC modulates word production of words specifically in a second language (L2) by measuring the effects of anodal transcranial direct current stimulation (anodal-tDCS) over the DLPFC on picture naming and word translation and on event-related potentials (ERPs) and their sources. Twenty-six bilingual participants with "unbalanced" proficiency in two languages were given 20 min of 1.5 mA anodal or sham tDCS (double-blind stimulation design, counterbalanced stimulation order, 1-week intersession delay). The participants then performed the following tasks: verbal and non-verbal fluency during anodal-tDCS stimulation and first and second language (L1 and L2) picture naming and translation [forward (L1 → L2) and backward (L2 → L1)] immediately after stimulation. The electroencephalogram (EEG) was recorded during picture naming and translation. On the behavioral level, anodal-tDCS had an influence on non-verbal fluency but neither on verbal fluency, nor on picture naming and translation. EEG measures revealed significant interactions between Language and Stimulation on picture naming around 380 ms post-stimulus onset and Translation direction and Stimulation on translation around 530 ms post-stimulus onset. These effects suggest that L2 phonological retrieval and phoneme encoding are spatially and temporally segregated in the brain. We conclude that anodal-tDCS stimulation has an effect at a neural level on phonological processes and, critically, that DLPFC-mediated activation is a constraint on language production specifically in L2.

Posterior SMA Syndrome following subcortical stroke: contralateral akinesia reversed by visual feedback.

BACKGROUND: The supplementary motor area (SMA) plays a key role in motor programming and production and is involved in internally-cued movements. In neurological populations, SMA syndrome following a lesion to the "SMA proper" is characterized by transient impairment of voluntary movements and motor sequences. This syndrome is assumed to follow on from an interruption of the motor cortico-subcortical loop, and some case reports indicate that such a syndrome could occur after a brain lesion isolating the SMA from subcortical structures. AIM: To characterize the pattern of motor impairments in a patient whose stroke disconnects the SMA from the subcortical motor loop. METHOD: A patient developed a moderate transient left hemiparesis following a subcortical stroke in the right anterior cerebral artery area, which disconnected the SMA from basal ganglia. Eight days after the stroke, when the hemiparesis had regressed, the patient presented a specific SMA motor disorder of the left hand which manifested as an akinesia and was exacerbated when his visual attention was not directed towards his hand. We assessed finger tapping with left and right hands, eyes closed and open, in the left and right hemispace. We indexed movement speed as the number of taps filmed over 5-s periods. RESULTS: Left motor weakness (grasping strength of right hand: 49 kg and left hand: 41 kg) was resolved in a week. Ideomotor and ideational gestures and motor sequences were preserved. On the tapping task, left-hand tapping was slower than right-hand tapping. Critically, visual feedback improved tapping speed for the left, but not for the right, hand. The hemispace of the task execution had no effect on tapping performance. CONCLUSION: Our results suggest that SMA-basal ganglia disconnection decreases contralateral movement initiation and maintenance and this effect is partly compensated by visual cues.

Risk of coronary artery disease in women with history of pregnancies complicated by preeclampsia and LBW.

UNLABELLED: Women with a history of pregnancy complicated by preeclampsia or intrauterine growth restriction and low infant birth weight looks at a higher risk for subsequent ischemic heart disease. OBJECTIVE: To determine the relationship between pregnancy complications and maternal coronary artery disease (CAD) in the future. MATERIALS AND METHOD: We performed a case-control study on 690 patients (345 patients in each group) referred to Tehran Heart Center. Women with CAD were in the case group and women without CAD were in the control group. The history of pregnancy complications (including preeclampsia, low birth weight [LBW] delivery, preterm labor and gestational hypertension) was evaluated in the two groups. RESULTS: 12.5% of the patients in the case group had a history of preeclampsia, compared with the control group (1.7%). (p < 0. 0001). Seven percent of the patients in the case group and 0.9% of the patients in the control group had history of LBW delivery. The difference was significant (p < 0.0001). A history of preterm labor was recorded in 11% of cases and 3.2% of controls. Performing multivariate analysis showed that there is a strong association between preeclampsia and CAD (OR: 16.92; 95% CI; p < 0.0001), LBW delivery and CAD (OR: 6.52; 95% CI; p: 0.0038), and also between high parity and CAD. (OR: 1.135; 95% CI; p: 0.0479). CONCLUSION: Our results suggest preeclampsia, LBW delivery and high parity of the mother as independent risk factors for CAD in the future.

Poststroke fatigue following minor infarcts: a prospective study.

OBJECTIVE: To explore the potential relationship between fatigue following strokes and poststroke mood, cognitive dysfunction, disability, and infarct site and to determine the predictive factors in the development of poststroke fatigue (PSF) following minor infarcts. METHODS: Ninety-nine functionally active patients aged less than 70 years with a first, nondisabling stroke (NIH Stroke Scale score ≤6 in acute phase and ≤3 after 6 months, modified Rankin Scale score ≤1 at 6 months) were assessed during the acute phase and then at 6 (T1) and 12 months (T2) after their stroke. Scores in the Fatigue Assessment Inventory were described and correlated to age, gender, neurologic and functional impairment, lesion site, mood scores, neuropsychological data, laboratory data, and quality of life at T1 and T2 using a multivariate logistic regression analysis in order to determine which variables recorded at T1 best predicted fatigue at T2. RESULT: As many as 30.5% of the patients at T1 and 34.7% at T2 (11.6% new cases between T1 and T2) reported fatigue. At both 6 and 12 months, there was a significant association between fatigue and a reduction in professional activity. Attentional-executive impairment, depression, and anxiety levels remained associated with PSF throughout this time period, underlining the critical role of these variables in the genesis of PSF. There was no significant association between the lesion site and PSF. CONCLUSION: This study suggests that attentional and executive impairment, as well as depression and anxiety, may play a critical role in the development of PSF.