Sensorized Assessment of Dynamic Locomotor Imagery in People with Stroke and Healthy Subjects.

Dynamic motor imagery (dMI) is a motor imagery task associated with movements partially mimicking those mentally represented. As well as conventional motor imagery, dMI has been typically assessed by mental chronometry tasks. In this paper, an instrumented approach was proposed for quantifying the correspondence between upper and lower limb oscillatory movements performed on the spot during the dMI of walking vs. during actual walking. Magneto-inertial measurement units were used to measure limb swinging in three different groups: young adults, older adults and stroke patients. Participants were tested in four experimental conditions: (i) simple limb swinging; (ii) limb swinging while imagining to walk (dMI-task); (iii) mental chronometry task, without any movement (pure MI); (iv) actual level walking at comfortable speed. Limb swinging was characterized in terms of the angular velocity, frequency of oscillations and sinusoidal waveform. The dMI was effective at reproducing upper limb oscillations more similar to those occurring during walking for all the three groups, but some exceptions occurred for lower limbs. This finding could be related to the sensory feedback, stretch reflexes and ground reaction forces occurring for lower limbs and not for upper limbs during walking. In conclusion, the instrumented approach through wearable motion devices adds significant information to the current dMI approach, further supporting their applications in neurorehabilitation for monitoring imagery training protocols in patients with stroke.

An ecological approach to the behavioral assessment of executive functions in anorexia nervosa.

The use of ecological tests to assess executive functions (EFs) in patients with anorexia nervosa (AN) has not examined extensively. The objective of this study was to analyze and compare the performance of patients with AN and healthy controls (HCs) on standard versus ecologically valid tests on EFs. Sixty-two females aged between 16 and 42 who were diagnosed with AN and 70 matched HCs completed 2 neuropsychological test batteries: standard tests (WCST, TMT, Stroop, ToL, fluency test) and the Behavioral Assessment of Dysexecutive Syndrome (BADS). On the standard tests, patients with AN produced more perseverative response and were slower than HCs in the TMT; in contrast, they scored as well as HCs on tasks that assessed categorization, interference in color naming, planning and semantic fluency. Conversely, there were differences in the ecological tests with patients with AN systematically slower in the resolution of complex tasks. Results demonstrated the power of ecological tests in capturing selective impairments in multifaceted and unstructured tests. Patients with AN experienced systematic deceleration in the resolution of ecological tasks. Also, the increased time needed to solve the tasks, was not reflected in overall improvement in performance. This evidence is further discussed with respect to central coherence.

The assessment of hemineglect syndrome with cancellation tasks: a comparison between the Bells test and the Apples test.

Unilateral spatial neglect (USN) is a frequent consequence of acquired brain injury, especially following right hemisphere damage. Traditionally, unilateral spatial neglect is assessed with cancellation tests such as the Bells test. Recently, a new cancellation test, the Apples test, has been proposed. The present study aims at comparing the accuracy of these two tests in detecting hemispatial neglect, on a sample of 56 right hemisphere stroke patients with a diagnosis of USN. In order to evaluate the agreement between the Apples and Bells tests, Cohen's kappa and McNemar's test were used to assess differences between the two methods of evaluation. Poor agreement and statistically significant differences emerged between the Apples and Bells tests. Overall, the Apples test was significantly more sensitive than the Bells test in detecting USN. Based on these results, the use of the Apples test for peripersonal neglect assessment is therefore highly recommended.

Rasch analysis of the Rivermead Mobility Index: a study using mobility measures of first-stroke inpatients.

OBJECTIVE: To evaluate the validity and item unidimensionality of the Rivermead Mobility Index (RMI) by using Rasch analysis. DESIGN: Application of Rasch analysis on the RMI partial data set. SETTING: A stroke program at a rehabilitation hospital in Italy. PARTICIPANTS: A total of 308 consecutive patients (155 women, 153 men; avg age, 62.79+/-11.94 y) hospitalized between 1990 and 1996. Average interval between stroke onset and admission was 52.48+/-36.22 days. INTERVENTION: Medical inpatient rehabilitation. MAIN OUTCOME MEASURES: Patients' mobility status was assessed using the RMI administered at admission and discharge. Ratings were assigned by 4 staff members working as a team. We performed separate Rasch analyses on the RMI data, gathered from different groups of first stroke inpatients examined before and after rehabilitation treatment. RESULTS: asch analysis showed the overall good validity of the RMI, except for item 15, which did not fit the unidimensional continuum estimated through the Rasch rating model. CONCLUSION: The RMI is a unidimensional scale with a hierarchy of easy-to-hard test questions. Item difficulty level was stable when processed on different groups of patients assessed on different occasions.