scholarly journals Dynamics of language reorganization after left temporo-parietal and frontal stroke

Brain ◽  
2020 ◽  
Vol 143 (3) ◽  
pp. 844-861 ◽  
Author(s):  
Anika Stockert ◽  
Max Wawrzyniak ◽  
Julian Klingbeil ◽  
Katrin Wrede ◽  
Dorothee Kümmerer ◽  
...  
Keyword(s):  
Functional Mri ◽  
Chronic Phase ◽  
Global Network ◽  
Lesion Location ◽  
Post Stroke ◽  
Language Functions ◽  
Language Recovery ◽  
Patient Groups ◽  
The Impact ◽  
General Networks

Abstract The loss and recovery of language functions are still incompletely understood. This longitudinal functional MRI study investigated the neural mechanisms underlying language recovery in patients with post-stroke aphasia putting particular emphasis on the impact of lesion site. To identify patterns of language-related activation, an auditory functional MRI sentence comprehension paradigm was administered to patients with circumscribed lesions of either left frontal (n = 17) or temporo-parietal (n = 17) cortex. Patients were examined repeatedly during the acute (≤1 week, t1), subacute (1–2 weeks, t2) and chronic phase (>6 months, t3) post-stroke; healthy age-matched control subjects (n = 17) were tested once. The separation into two patient groups with circumscribed lesions allowed for a direct comparison of the contributions of distinct lesion-dependent network components to language reorganization between both groups. We hypothesized that activation of left hemisphere spared and perilesional cortex as well as lesion-homologue cortex in the right hemisphere varies between patient groups and across time. In addition, we expected that domain-general networks serving cognitive control independently contribute to language recovery. First, we found a global network disturbance in the acute phase that is characterized by reduced functional MRI language activation including areas distant to the lesion (i.e. diaschisis) and subsequent subacute network reactivation (i.e. resolution of diaschisis). These phenomena were driven by temporo-parietal lesions. Second, we identified a lesion-independent sequential activation pattern with increased activity of perilesional cortex and bilateral domain-general networks in the subacute phase followed by reorganization of left temporal language areas in the chronic phase. Third, we observed involvement of lesion-homologue cortex only in patients with frontal but not temporo-parietal lesions. Fourth, irrespective of lesion location, language reorganization predominantly occurred in pre-existing networks showing comparable activation in healthy controls. Finally, we detected different relationships of performance and activation in language and domain-general networks demonstrating the functional relevance for language recovery. Our findings highlight that the dynamics of language reorganization clearly depend on lesion location and hence open new perspectives for neurobiologically motivated strategies of language rehabilitation, such as individually-tailored targeted application of neuro-stimulation.

scholarly journals Brain disconnectivity mapping of post-stroke fatigue

2020 ◽  
Author(s):  
Kristine M. Ulrichsen ◽  
Knut K. Kolskår ◽  
Geneviève Richard ◽  
Dag Alnæs ◽  
Erlend S. Dørum ◽  
...  
Keyword(s):  
Bayes Factor ◽  
Linear Models ◽  
Chronic Phase ◽  
Stroke Patients ◽  
Lesion Location ◽  
Post Stroke ◽  
Novel Approach ◽  
Alternative Hypotheses ◽  
Brain Correlates ◽  
Methodological Considerations

AbstractStroke patients commonly suffer from post stroke fatigue (PSF). Despite a general consensus that brain perturbations constitute a precipitating event in the multifactorial etiology of PSF, the specific predictive value of conventional lesion characteristics such as size and localization remain unclear. The current study represents a novel approach to assess the neural correlates of PSF in chronic stroke patients. While previous research has focused primarily on lesion location or size, with mixed or inconclusive results, we targeted the extended structural network implicated by the lesion, and evaluated the added explanatory value of a disconnectivity approach with regards to the brain correlates of PSF. To this end, we estimated individual brain disconnectome maps in 84 stroke survivors in the chronic phase (≥ 3 months post stroke) using information about lesion location and normative white matter pathways obtained from 170 healthy individuals. PSF was measured by the Fatigue Severity Scale (FSS). Voxel wise analyses using non-parametric permutation-based inference were conducted on disconnectome maps to estimate regional effects of disconnectivity. Associations between PSF and global disconnectivity and clinical lesion characteristics were tested by linear models, and we estimated Bayes factor to quantify the evidence for the null and alternative hypotheses, respectively. The results revealed no significant associations between PSF and disconnectome measures or lesion characteristics, with moderate evidence in favor of the null hypothesis. These results suggest that symptoms of post-stroke fatigue are not simply explained by lesion characteristics or brain disconnectome measures in stroke patients in a chronic phase, and are discussed in light of methodological considerations.

scholarly journals The regulation of glycemia in the recovery phase after stroke counteracts the detrimental effect of obesity-induced type 2 diabetes on neurological recovery

2020 ◽  
Author(s):  
Ada Admin ◽  
Ingrid Lovise Augestad ◽  
Hiranya Pintana ◽  
Martin Larsson ◽  
Camilla Krizhanovskii ◽  
...  
Keyword(s):  
Chronic Phase ◽  
Clinical Situation ◽  
Recovery Phase ◽  
Artery Occlusion ◽  
Stroke Recovery ◽  
Neurological Recovery ◽  
Standard Diet ◽  
Dipeptidyl Peptidase 4 ◽  
Post Stroke ◽  
The Impact

The interplay between obesity and T2D in post-stroke recovery is unclear. Moreover, the impact of glucose control during the chronic phase after stroke is undetermined. <p>We investigated whether obesity-induced T2D impairs neurological recovery after stroke by using a clinically relevant experimental design. We also investigated the potential efficacy of two clinically-used T2D drugs: the dipeptidyl peptidase-4 inhibitor linagliptin and the sulfonylurea glimepiride.</p> <p>We induced transient middle cerebral artery occlusion (tMCAO) in T2D/obese mice (after 7 months of high-fat diet (HFD)) and age-matched controls. After stroke, we replaced HFD with standard diet for 8 weeks to mimic the post-stroke clinical situation. Linagliptin or glimepiride were administered daily from 3 days after tMCAO for 8 weeks.<b> </b>We assessed neurological recovery weekly by upper-limb grip strength. Brain damage, neuroinflammation, stroke-induced neurogenesis and atrophy of parvalbumin (PV)+ interneurons were quantified by immunohistochemistry.</p> <p>T2D/obesity impaired post-stroke neurological recovery in association with hyperglycemia, neuroinflammation and atrophy of PV+ interneurons. Both drugs counteracted these effects. In non-diabetic mice, only linagliptin accelerated recovery.</p> These findings shed light on the interplay between obesity and T2D in stroke recovery. Moreover, they promote the use of rehabilitative strategies based on efficacious glycemia regulation, even if initiated days after stroke.

scholarly journals The regulation of glycemia in the recovery phase after stroke counteracts the detrimental effect of obesity-induced type 2 diabetes on neurological recovery

2020 ◽  
Author(s):  
Ada Admin ◽  
Ingrid Lovise Augestad ◽  
Hiranya Pintana ◽  
Martin Larsson ◽  
Camilla Krizhanovskii ◽  
...  
Keyword(s):  
Chronic Phase ◽  
Clinical Situation ◽  
Recovery Phase ◽  
Artery Occlusion ◽  
Stroke Recovery ◽  
Neurological Recovery ◽  
Standard Diet ◽  
Dipeptidyl Peptidase 4 ◽  
Post Stroke ◽  
The Impact

The interplay between obesity and T2D in post-stroke recovery is unclear. Moreover, the impact of glucose control during the chronic phase after stroke is undetermined. <p>We investigated whether obesity-induced T2D impairs neurological recovery after stroke by using a clinically relevant experimental design. We also investigated the potential efficacy of two clinically-used T2D drugs: the dipeptidyl peptidase-4 inhibitor linagliptin and the sulfonylurea glimepiride.</p> <p>We induced transient middle cerebral artery occlusion (tMCAO) in T2D/obese mice (after 7 months of high-fat diet (HFD)) and age-matched controls. After stroke, we replaced HFD with standard diet for 8 weeks to mimic the post-stroke clinical situation. Linagliptin or glimepiride were administered daily from 3 days after tMCAO for 8 weeks.<b> </b>We assessed neurological recovery weekly by upper-limb grip strength. Brain damage, neuroinflammation, stroke-induced neurogenesis and atrophy of parvalbumin (PV)+ interneurons were quantified by immunohistochemistry.</p> <p>T2D/obesity impaired post-stroke neurological recovery in association with hyperglycemia, neuroinflammation and atrophy of PV+ interneurons. Both drugs counteracted these effects. In non-diabetic mice, only linagliptin accelerated recovery.</p> These findings shed light on the interplay between obesity and T2D in stroke recovery. Moreover, they promote the use of rehabilitative strategies based on efficacious glycemia regulation, even if initiated days after stroke.

scholarly journals New Treatment Strategy Using Repetitive Transcranial Magnetic Stimulation for Post-Stroke Aphasia

Diagnostics ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1853
Author(s):  
Takatoshi Hara ◽  
Masahiro Abo
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Right Hemisphere ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Chronic Phase ◽  
Functional Improvement ◽  
Language Function ◽  
Post Stroke ◽  
Language Functions ◽  
New Treatment

Repetitive transcranial magnetic stimulation (rTMS) for post-stroke aphasia (PSA) has been suggested to promote improvement of language function when used in combination with rehabilitation. However, many challenges remain. In some reports examined by category of language function, only naming has good evidence of improvement, and the improvement effect on other language modalities is low. Therefore, it is necessary to establish methods that contribute to the improvement of language functions other than naming. Therapeutic methods for PSA based on the mechanism of rTMS are mainly inhibitory stimulation methods for language homologous areas. However, the mechanisms of these methods are controversial when inferred from the process of recovery of language function. Low-frequency rTMS applied to the right hemisphere has been shown to be effective in the chronic phase of PSA, but recent studies of the recovery process of language function indicate that this method is unclear. Therefore, it has been suggested that evaluating brain activity using neuroimaging contributes to confirming the effect of rTMS on PSA and the elucidation of the mechanism of functional improvement. In addition, neuroimaging-based stimulation methods (imaging-based rTMS) may lead to further improvements in language function. Few studies have examined neuroimaging and imaging-based rTMS in PSA, and further research is required. In addition, the stimulation site and stimulation parameters of rTMS are likely to depend on the time from onset to intervention. However, there are no reports of studies in patients between 90 and 180 days after onset. Therefore, research during this period is required. New stimulation methods, such as multiple target methods and the latest neuroimaging methods, may contribute to the establishment of new knowledge and new treatment methods in this field.

Neuro-Clinical Signatures of Language Impairments: A Theoretical Framework for Function-to-structure Mapping in Clinics

2020 ◽  
Vol 20 (9) ◽  
pp. 800-811 ◽  
Author(s):  
Ferath Kherif ◽  
Sandrine Muller
Keyword(s):  
Brain Mapping ◽  
Theoretical Framework ◽  
Brain Regions ◽  
Language Impairments ◽  
Structure Mapping ◽  
Language Functions ◽  
The Past ◽  
Language Recovery ◽  
The Brain ◽  
Bow Tie

In the past decades, neuroscientists and clinicians have collected a considerable amount of data and drastically increased our knowledge about the mapping of language in the brain. The emerging picture from the accumulated knowledge is that there are complex and combinatorial relationships between language functions and anatomical brain regions. Understanding the underlying principles of this complex mapping is of paramount importance for the identification of the brain signature of language and Neuro-Clinical signatures that explain language impairments and predict language recovery after stroke. We review recent attempts to addresses this question of language-brain mapping. We introduce the different concepts of mapping (from diffeomorphic one-to-one mapping to many-to-many mapping). We build those different forms of mapping to derive a theoretical framework where the current principles of brain architectures including redundancy, degeneracy, pluri-potentiality and bow-tie network are described.

scholarly journals Influence of Physical Activity and Socio-Economic Status on Depression and Anxiety Symptoms in Patients after Stroke

2021 ◽  
Vol 18 (15) ◽  
pp. 8058
Author(s):  
Małgorzata Paprocka-Borowicz ◽  
Mona Wiatr ◽  
Maria Ciałowicz ◽  
Wojciech Borowicz ◽  
Agnieszka Kaczmarek ◽  
...  
Keyword(s):  
Physical Activity ◽  
Physical Therapy ◽  
Economic Status ◽  
Depression Scale ◽  
Post Stroke ◽  
Positive Effects ◽  
Socio Economic Status ◽  
Treatment Of Depression ◽  
Post Stroke Depression ◽  
The Impact

Stroke is a high-risk factor for depression. Neurological rehabilitation is greatly difficult and often does not include treatment of depression. The post-stroke depression plays an important role in the progress of treatment, health, and the life of the patient. The appropriate treatment of depression could improve the quality of life of the patient and their family. The study aimed to evaluate the impact of physical activity and socio-economic status of the patient on the effectiveness of recovery from depression and the severity of the symptoms of depression. The study was conducted with 40 patients after stroke aged 42–82 years, and included 10 women and 30 men who were hospitalized for two weeks. The severity of depression/anxiety (D/A) symptoms were evaluated two times; at admission and after two weeks of physical therapy. The hospital anxiety and depression scale (HADS) questionnaire was used for this purpose. Socio-economic status was evaluated by several simple questions. It was revealed that physical therapy has a positive influence on mental state. The severity of D/A symptoms after stroke is related to the financial status of the patients (2 = 11.198, p = 0.024). The state of health (2 = 20.57, p = 0.022) and physical fitness (2 = 12.95, p = 0.044) changed the severity of symptoms of anxiety and depressive disorders. The kinesiotherapy in the group of patients with post-stroke depression had positive effects; however, economic and health conditions may influence the prognosis of the disease.

scholarly journals Measuring capability wellbeing in adults at different stages of life for use in economic evaluation of health and care interventions: a qualitative investigation in people requiring kidney care

2021 ◽  
Author(s):  
Paul Mark Mitchell ◽  
Samantha Husbands ◽  
Sabina Sanghera ◽  
Fergus John Caskey ◽  
Jemima Scott ◽  
...  
Keyword(s):  
Life Stage ◽  
Structured Interview ◽  
Health Conditions ◽  
Economic Evaluations ◽  
Qualitative Investigation ◽  
Key Factors ◽  
Younger Adults ◽  
Patient Groups ◽  
The Life Course ◽  
The Impact

Abstract Purpose Capability wellbeing measures, such as the ICECAP measures, have been proposed for use in economic evaluations to capture broader outcomes of health and care interventions. The ICECAP measures have been developed to reflect capabilities at different stages of life. Some patient groups include patients of different ages and at different stages of life, so it is not always apparent which ICECAP measure is most relevant. This study explores the impact of age and life stage on completion, where both ICECAP-A and ICECAP-O were completed by the same patient. Methods A think-aloud study, and an associated semi-structured interview were conducted with people receiving kidney care as a renal outpatient, kidney transplant outpatient, or through receiving facility-based haemodialysis. Qualitative analysis focused on (1) differences in responses across measures by individuals, where attributes had conceptual overlap, (2) key factors in self-reported capability levels, and (3) measure preference. Results Thirty participants were included in the study, with a mix of older and younger adults. Attributes with similar wording across measures produced similar responses compared to attributes where wording differed. Age and health were key factors for self-reported capability levels. ICECAP-A was slightly preferred overall, including by older adults. Conclusion This study suggests use of ICECAP-A in patients with certain chronic health conditions that include a mix of adults across the life course. This study highlights the importance of considering the stage of life when using capability measures and in economic evaluations of health and care interventions more generally.

Cognition predicts days-alive-out-of-hospital after LVAD implantation

2021 ◽  
pp. 039139882110184
Author(s):  
Marykay A Pavol ◽  
Amelia K Boehme ◽  
Melana Yuzefpolskaya ◽  
Mathew S Maurer ◽  
Jesus Casida ◽  
...  
Keyword(s):  
Linear Regression ◽  
Regression Model ◽  
Linear Regression Model ◽  
Left Ventricular ◽  
Motor Speed ◽  
Ventricular Assist ◽  
Hospitalization Rates ◽  
Left Ventricular Assist ◽  
Patient Groups ◽  
The Impact

Objective: Cognition influences hospitalization rates for a variety of patient groups but this association has not been examined in heart failure (HF) patients undergoing left ventricular assist device (LVAD) implantation. We used cognition to predict days-alive-out-of-hospital (DAOH) in patients after LVAD surgery. Methods: We retrospectively identified 59 HF patients with cognitive assessment prior to LVAD. Cognitive tests of attention, memory, language, and visual motor speed were averaged into one score. DAOH was converted to a percentage based on total days from LVAD surgery to either heart transplant or 900 days post-LVAD. Variables significantly associated with DAOH in univariate analyses were included in a linear regression model to predict DAOH. Results: A linear regression model including LVAD type (continuous or pulsatile flow) and cognition significantly predicted DAOH (F(2,54) = 6.44, p = 0.003, R2 = .19). Inspection of each variable revealed that cognition was a significant predictor in the model (β = .11, SE = .04, p = 0.007) but LVAD type was not ( p = 0.08). Conclusions: Cognitive performance assessed prior to LVAD implantation predicted how much time patients spent out of the hospital following surgery. Further studies are warranted to identify the impact of pre-LVAD cognition on post-LVAD hospitalization.

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