French Phonological Component Analysis and aphasia recovery: A bilingual perspective on behavioral and structural data.

Studies show bilingualism entails an advantage in cognitive control tasks. There is evidence of a bilingual advantage in the context of aphasia, resulting in better cognitive outcomes and recovery in bilingual persons with aphasia compared to monolingual peers. This bilingual advantage also results in structural changes in the right hemisphere gray matter. Very few studies have examined the so-called bilingual advantage by reference to specific anomia therapy efficacy. This study aims to compare the effect of French-Phonological Component Analysis (Fr-PCA) in monolinguals and bilingual persons with aphasia, both at the linguistic and cognitive control level, and to examine the structural impact of left hemisphere lesion location and right hemisphere structural data. Eight participants with chronic aphasia received Fr-PCA for a total of 15 h over 5 weeks. The results showed improved accuracy for treated words and generalization to untreated items and discourse in both groups, and improved Flanker task performance for some participants. Bilingual participants improved more than monolinguals for picture-naming tasks and narrative discourse. Damage to the left postcentral gyrus and the middle frontal gyrus was associated with less therapy-induced improvement. Additionally, left hemisphere damage to the inferior parietal gyrus and postcentral gyrus was associated with reduced cognitive control pre-therapy. Undamaged right hemisphere cortical thicknesses were significantly different between groups; the inferior frontal gyrus and the middle frontal gyrus were greater for the bilingual participants and correlated with cognitive control skills. These results suggest a bilingual advantage in anomia recovery following Fr-PCA, potentially resulting from enhanced cognitive control abilities that could be supported by right hemisphere neural reserve.

Chronic Neuroleptic-Induced Parkinsonism Examined With Positron Emission Tomography.

BACKGROUND: Neuroleptic drug-induced parkinsonism (NIP) is a leading cause of parkinsonism, particularly in aging. Based on abnormal dopamine transporter scan results, individuals displaying chronic NIP are often diagnosed with Lewy-body Parkinson's disease (PD), but this assumption needs further substantiation. OBJECTIVE: To quantitate the profile of striatal dopaminergic nerve terminal density in NIP relative to PD. METHODS: We used the positron emission tomography ligand [11 C](+)-dihydrotetrabenazine targeting vesicular monoamine transporter type 2 (VMAT2) binding sites and collected various clinical parameters (motor ratings, olfaction, polysomnography to document rapid eye movement sleep muscle activity, quantitative sensory testing for pain thresholds) possibly predicting binding results in patients older than age 50 living with schizophrenia spectrum disorders under long-term stable antipsychotic drug treatment, with (N = 11) or without (N = 11) chart documention of chronic NIP, and compared them to healthy volunteers (N = 11) and others medicated for PD (N = 12). RESULTS: Striatal VMAT2 binding was dichotomous in the NIP group between those with spared (N = 5) or low (N = 6) PD-like values. Striatal binding reduction in the low VMAT2-NIP group was asymmetric without the gradient of maximal involvement in the posterior putamen typical of PD. Anosmia was the only nonmotor parameter measured matching the abnormal striatal VMAT2 binding status. CONCLUSION: These preliminary observations suggest that striatal VMAT2 binding is abnormal in a fraction of chronic NIP cases and differs in spatial distribution from PD. The possibility of a drug-induced axonopathy and resultant synaptopathy, as well as the evolution of the binding deficit, warrant further longitudinal studies in a large cohort. © 2020 International Parkinson and Movement Disorder Society.

Alerting, Orienting, and Executive Control: The Effect of Bilingualism and Age on the Subcomponents of Attention.

Life-long experience of using two or more languages has been shown to enhance cognitive control abilities in young and elderly bilinguals in comparison to their monolingual peers. This advantage has been found to be larger in older adults in comparison to younger adults, suggesting that bilingualism provides advantages in cognitive control abilities. However, studies showing this effect have used a variety of tasks (Simon Task, Stroop task, Flanker Task), each measuring different subcomponents of attention and raising mixed results. At the same time, attention is not a unitary function but comprises of subcomponents which can be distinctively addressed within the Attention Network Test (ANT) (1, 2). The purpose of this work was to examine the neurofunctional correlates of the subcomponents of attention in healthy young and elderly bilinguals taking into account the L2 age of acquisition, language usage, and proficiency. Participants performed an fMRI version of the ANT task, and speed, accuracy, and BOLD data were collected. As expected, results show slower overall response times with increasing age. The ability to take advantage of the warning cues also decreased with age, resulting in reduced alerting and orienting abilities in older adults. fMRI results showed an increase in neurofunctional activity in the frontal and parietal areas in elderly bilinguals when compared to young bilinguals. Furthermore, higher L2 proficiency correlated negatively with activation in frontal area, and that faster RTs correlated negatively with activation in frontal and parietal areas. Such a correlation, especially with L2 proficiency was not present in young bilinguals and provides evidence for a bilingual advantage in the alerting subcomponent of attention that characterizes elderly bilinguals' performance. This study thus provides extra details about the bilingual advantage in the subcomponent of attention, in older bilinguals. Consequently, speaking more than one language impacts cognition and the brain later in life.

The Neural and Behavioral Correlates of Anomia Recovery following Personalized Observation, Execution, and Mental Imagery Therapy: A Proof of Concept.

The impact of sensorimotor strategies on aphasia recovery has rarely been explored. This paper reports on the efficacy of personalized observation, execution, and mental imagery (POEM) therapy, a new approach designed to integrate sensorimotor and language-based strategies to treat verb anomia, a frequent aphasia sign. Two participants with verb anomia were followed up in a pre-/posttherapy fMRI study. POEM was administered in a massed stimulation schedule, with personalized stimuli, resulting in significant improvement in both participants, with both trained and untrained items. Given that the latter finding is rarely reported in the literature, the evidence suggests that POEM favors the implementation of a word retrieval strategy that can be integrated and generalized. Changes in fMRI patterns following POEM reflect a reduction in the number of recruited areas supporting naming and the recruitment of brain areas that belong to the language and mirror neuron systems. The data provide evidence on the efficacy of POEM for verb anomia, while pointing to the added value of combined language and sensorimotor strategies for recovery from verb anomia, contributing to the consolidation of a word retrieval strategy that can be better generalized to untrained words. Future studies with a larger sample of participants are required to further explore this avenue.

Pedunculopontine network dysfunction in Parkinson's disease with postural control and sleep disorders.

BACKGROUND: The objective of this study was to investigate pedunculopontine nucleus network dysfunctions that mediate impaired postural control and sleep disorder in Parkinson's disease. METHODS: We examined (1) Parkinson's disease patients with impaired postural control and rapid eye movement sleep behavior disorder (further abbreviated as sleep disorder), (2) Parkinson's disease patients with sleep disorder only, (3) Parkinson's disease patients with neither impaired postural control nor sleep disorder, and (4) healthy volunteers. We assessed postural control with clinical scores and biomechanical recordings during gait initiation. Participants had video polysomnography, daytime sleepiness self-evaluation, and resting-state functional MRIs. RESULTS: Patients with impaired postural control and sleep disorder had longer duration of anticipatory postural adjustments during gait initiation and decreased functional connectivity between the pedunculopontine nucleus and the supplementary motor area in the locomotor network that correlated negatively with the duration of anticipatory postural adjustments. Both groups of patients with sleep disorder had decreased functional connectivity between the pedunculopontine nucleus and the anterior cingulate cortex in the arousal network that correlated with daytime sleepiness. The degree of dysfunction in the arousal network was related to the degree of connectivity in the locomotor network in all patients with sleep disorder, but not in patients without sleep disorder or healthy volunteers. CONCLUSIONS: These results shed light on the functional neuroanatomy of pedunculopontine nucleus networks supporting the clinical manifestation and the interdependence between sleep and postural control impairments in Parkinson's disease. © 2016 International Parkinson and Movement Disorder Society.