title: Smartphone-based tactile cueing improves motor performance in Parkinson's disease.
abstract: BACKGROUND
  Visual and auditory cueing improve functional performance in Parkinson's disease (PD) patients. However, audiovisual processing shares many cognitive resources used for attention-dependent tasks such as communication, spatial orientation, and balance. Conversely, tactile cues (TC) may be processed faster, with minimal attentional demand, and may be more efficient means for modulating motor-cognitive performance. In this study we aimed to investigate the efficacy and limitations of TC for modulating simple (heel tapping) and more complex (walking) motor tasks (1) over a range of cueing intervals, (2) with/without a secondary motor task (holding tray with cups of water).
  
  
  METHODS
  Ten PD patients (71 ± 9 years) and 10 healthy controls (69 ± 7 years) participated in the study. TCs was delivered through a smart phone attached to subjects' dominant arm and were controlled by a custom-developed Android application.
  
  
  RESULTS
  PD patients and healthy controls were able to use TC to modulate heel tapping (F(3.8,1866.1) = 1008.1, p < 0.001), and partially modulate walking (F(3.5,1448.7) = 187.5, p < 0.001) tasks. In the walking task, PD patients modulated performance over a narrower range of cueing intervals (R(2) = 0.56) than healthy controls (R(2) = 0.84; group difference F(3.5,1448.7) = 8.6, p < 0.001). TC diminished synchronization error associated with performance of secondary motor task during walking in PD patients and healthy controls (main effect of Task (F(1,494) = 0.4; p = 0.527), Task X Group interaction (F(1,494) = 0.5; p = 0.493)).
  
  
  CONCLUSIONS
  This study expands modalities of TC usage for movement modulation and motor-cognitive integration in PD patients. The smartphone TC application was validated as a user-friendly movement modulation aid.
authors.affiliation: University of Houston, Center for Neuromotor and Biomechanics Research at The National Center for Human Performance, 2450 Holcombe Boulevard, Houston, TX 77021, USA. Electronic address: vivkovic@nmr.mgh.harvard.edu.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ivkovic
authors.affiliation: University of Houston, Center for Neuromotor and Biomechanics Research at The National Center for Human Performance, 2450 Holcombe Boulevard, Houston, TX 77021, USA; Movement Disorders and Neurorehabilitation Center, Methodist Neurological Institute, 6560 Fannin Street, Suite 802, Houston, TX 77030, USA. Electronic address: stafisher@saint-lukes.org.
authors.forename: Stanley
authors.initials: S
authors.lastname: Fisher
authors.affiliation: University of Houston, Center for Neuromotor and Biomechanics Research at The National Center for Human Performance, 2450 Holcombe Boulevard, Houston, TX 77021, USA. Electronic address: whpalosk@central.uh.edu.
authors.forename: William H
authors.initials: WH
authors.lastname: Paloski
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D063731:Mobile Applications; D009048:Motor Skills; D010300:Parkinson Disease / Q000503:physiopathology / Q000534:rehabilitation*; D010812:Physical Stimulation / Q000379:methods; D000068997:Smartphone; D013647:Task Performance and Analysis; D014732:Vibration
keywords: Cueing; Movement; Parkinson's; Smartphone; Tactile