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Varghese, R.

Publications and source records attributed to Varghese, R..

2 recordsLinked to original sources

Predictors of arm non-use in chronic stroke: a preliminary investigation

BackgroundThe phenomenon of non-use after stroke is characterized by failure to use the contralesional arm despite adequate capacity. It has been suggested that non-use is a consequence of the greater effort and/or attention required to use the affected limb, but such accounts have not been tested, and we have poor understanding of the characteristics of individuals who exhibit non-use.\n\nObjectiveWe aimed to provide preliminary evidence regarding the demographic, neuropsychological, and psychological factors that may influence non-use in chronic stroke.\n\nMethodsTwenty chronic stroke survivors (10 left and 10 right hemisphere stroke) with mild-to-moderate sensory-motor impairment on the upper extremity Fugl-Meyer (UEFM) were assessed with the Actual Amount of Use Test (AAUT), which measures the disparity between amount of use and quality of movement in \"spontaneous\" versus \"forced\" conditions. Participants were als assessed with measures of limb apraxia, spatial neglect, attention/arousal, and self-efficacy (confidence in arm movement). Using stepwise multiple regression, we determined whether demographic information and/or performance on these measures predicted AAUT non-use scores.\n\nResultsScores on the UEFM as well as attention/arousal and self-efficacy predicted the degree of non-use. Attention/arousal predicted non-use above and beyond UEFM.\n\nConclusionsGiven the complexity of the non-use phenomenon, it follows that a combination of impairment, attention/arousal, and perceived confidence predicted non-use behavior. That a measure of attention/arousal predicted non-use behavior above and beyond sensory-motor functioning highlights the importance of motivated engagement to drive use of the paretic limb. Larger-scale studies incorporating additional measures (e.g., mental health, lesion volume and white matter connectivity, pain, motivation) will be important for future investigations.

neuroscience

Relationship Between Motor Capacity of the Contralesional and Ipsilesional Hand Depends on the Side of Stroke

There is considerable evidence that after a stroke, ipsilesional deficits increase as contralesional impairment increases. Here, we asked if the relationship between the motor capacities of the two limbs differs based on the side of stroke. Forty-two pre-morbidly right-handed chronic stroke survivors (left hemisphere damage, LHD = 21) with mild-to-moderate paresis performed distal items of the Wolf Motor Function Test (dWMFT). We found that compared to RHD, the relationship between contralesional arm impairment (Upper Extremity Fugl-Meyer, UEFM) and ipsilesional hand motor capacity was stronger (R2LHD= 0.42; R2RHD < 0.01; z = 2.12; p = 0.03) and the slope was steeper (t = -2.03; p = 0.04) in LHD. Similarly, the relationship between contralesional dWMFT and ipsilesional hand motor capacity was stronger (R2LHD= 0.65; R2RHD= 0.09; z = 2.45; p = 0.01) and the slope was steeper (t = 2.03; p = 0.04) in LHD compared to RHD. Multiple regression analysis confirmed the presence of an interaction between contralesional UEFM and side of stroke ({beta}3= 0.66 {+/-} 0.30; p = 0.024) but only trended towards significance for the interaction between contralesional dWMFT and side of stroke ({beta}3= -0.51 {+/-} 0.34; p = 0.05). Results were confirmed after removal of potential outliers. Our findings suggest that the relationship between contra- and ipsi-lesional motor capacity depends on the side of stroke, such that the inter-limb relationship is stronger for stroke survivors with left hemisphere damage compared to those with right hemisphere damage.

neuroscience