Selection and application of familiar and novel tools in patients with left and right hemispheric stroke: Psychometrics and normative data

Ilka Buchmann,Jennifer Randerath

doi:10.1016/j.cortex.2017.06.001

Abstract

Frequently left brain damage (LBD) leads to limb apraxia, a disorder that can affect tool-use. Despite its impact on daily life, classical tests examining the pantomime of tool-use and imitation of gestures are seldom applied in clinical practice. The study's aim was to present a diagnostic approach which appears more strongly related to actions in daily life in order to sensitize applicants and patients about the relevance of the disorder before patients are discharged.Two tests were introduced that evaluate actual tool selection and tool-object-application: the Novel Tools (NTT) and the Familiar Tools (FTT) Test (parts of the DILA-S: Diagnostic Instrument for Limb Apraxia – Short Version). Normative data in healthy subjects (N = 82) was collected. Then the tests were applied in stroke patients with unilateral left brain damage (LBD: N = 33), a control right brain damage group (RBD: N = 20) as well as healthy age and gender matched controls (CL: N = 28, and CR, N = 18).The tests showed appropriate interrater-reliability and internal consistency as well as concurrent and divergent validity. To examine criterion validity based on the well-known left lateralization of limb apraxia, group comparisons were run. As expected, the LBD group demonstrated a high prevalence of tool-use apraxia (NTT: 36.4%, FTT: 48.5%) ranging from mild to severe impairment and scored worse than their control group (CL). A few RBD patients did demonstrate impairments in tool-use (NTT: 15%, FTT: 15%). On a group level they did not differ from their healthy controls (CR). Further, it was demonstrated that the selection and application of familiar and novel tools can be impaired selectively.Our study results suggest that real tool-use tests evaluating tool selection and tool application should be considered for standard diagnosis of limb apraxia in left as well as right brain damaged patients.

Highlights

The term apraxia refers to ‘higher level’ disorders of motor control (Goldenberg, 2013a)
The FTT is assumed to rely on both, on the retrieval of functional knowledge and object semantics from memory as well as on mechanical problem solving (Goldenberg & Spatt, 2009; Hodges, Spatt, & Patterson, 1999; Randerath et al, 2011). For this purpose we developed a Familiar Tools Test (FTT) and adapted the Novel Tools Test (NTT) from Goldenberg and Hagmann (1998b) for the here used DILA-S (Diagnostic Instrument for Limb Apraxia e Short Version)
In contrast to the NTT, Cut-Off values in the FTT, both in selection and application were found to be close to ceiling

Summary

Introduction

The term apraxia refers to ‘higher level’ disorders of motor control (Goldenberg, 2013a). Besides stroke or traumatic brain injury lesions, it can occur with neurodegenerative lesions such as dementia (e.g., Chandra, Isaac, & Abbas, 2015; Cotelli, Manenti, Brambilla, & Balconi, 2014) or corticobasal syndrome (e.g., Burrell, Hornberger, Vucic, Kiernan, & Hodges, 2014; Stamenova et al, 2015). It is tested by asking the patient to pantomime object use movements (e.g., “Show me how to use a toothbrush.”) or by imitation of gestures. Patients may choose the wrong objects (e.g., soap instead of toothpaste for brushing the teeth) and/or perform the movement wrongly or not at all (e.g., not moving the fork into the mouth or not even exploring the fork)

Methods

Results

Conclusion