Journal of Neurology

, Volume 265, Issue 6, pp 1365–1375 | Cite as

Quantitative assessment of finger tapping characteristics in mild cognitive impairment, Alzheimer’s disease, and Parkinson’s disease

  • David R. Roalf
  • Petra Rupert
  • Dawn Mechanic-Hamilton
  • Laura Brennan
  • John E. Duda
  • Daniel Weintraub
  • John Q. Trojanowski
  • David Wolk
  • Paul J. Moberg
Original Communication



Fine motor impairments are common in neurodegenerative disorders, yet standardized, quantitative measurements of motor abilities are uncommonly used in neurological practice. Thus, understanding and comparing fine motor abilities across disorders have been limited.


The current study compared differences in finger tapping, inter-tap interval, and variability in Alzheimer’s disease (AD), Parkinson’s disease (PD), mild cognitive impairment (MCI), and healthy older adults (HOA).


Finger tapping was measured using a highly sensitive light-diode finger tapper. Total number of finger taps, inter-tap interval, and intra-individual variability (IIV) of finger tapping was measured and compared in AD (n = 131), PD (n = 63), MCI (n = 46), and HOA (n = 62), controlling for age and sex.


All patient groups had fine motor impairments relative to HOA. AD and MCI groups produced fewer taps with longer inter-tap interval and higher IIV compared to HOA. The PD group, however, produced more taps with shorter inter-tap interval and higher IIV compared to HOA.


Disease-specific changes in fine motor function occur in the most common neurodegenerative diseases. The findings suggest that alterations in finger tapping patterns are common in AD, MCI, and PD. In addition, the present results underscore the importance of motor dysfunction even in neurodegenerative disorders without primary motor symptoms.


Alzheimer’s disease Parkinson’s disease Mild cognitive impairment Finger tapping Intra-individual variability 



The authors express appreciation to the research participants and staff of the Penn Memory Center/Clinical Core of the University of Pennsylvania Alzheimer’s Disease Center, the Parkinson’s Disease and Movement Disorders Center at the University of Pennsylvania, the Parkinson’s Disease Research, Education and Clinical Center (PADRECC) at the Philadelphia Veterans Affairs Medical Center and general neurology clinic at the University of Pennsylvania.

Author contributions

DRR: drafting/revising the manuscript, study concept or design, analysis or interpretation of data, accepts responsibility for conduct of research, and will give final approval, acquisition of data, statistical analysis, and study supervision. Dr. Roalf takes the role of Principal Investigator, has access to all of the data and takes responsibility for the data, accuracy of data analysis, and conduct of the research. Dr. Roalf will serve as the corresponding author. PR: drafting/revising the manuscript, analysis or interpretation of data, accepts responsibility for conduct of research, and will give final approval, acquisition of data, and statistical analysis. DM-H: study supervision, revising manuscript, accepts responsibility for conduct of research, and will give final approval. LB: study supervision, revising manuscript, accepts responsibility for conduct of research, and will give final approval. JD: study concept or design, accepts responsibility for conduct of research, and will give final approval, study supervision, and obtaining funding. DW: study concept or design, accepts responsibility for conduct of research and will give final approval, study supervision, and obtaining funding. JQT: study concept or design, accepts responsibility for conduct of research, and will give final approval, study supervision, and obtaining funding. DW: study concept or design, accepts responsibility for conduct of research, and will give final approval, study supervision, and obtaining funding. PJM: drafting/revising the manuscript, study concept or design, analysis or interpretation of data, accepts responsibility for conduct of research, and will give final approval, study supervision, and obtaining funding.


This work was supported by NIA AG10124, NIMH K01 MH102609 (Dr. Roalf), the Marian S. Ware Alzheimer’s Program/National Philanthropic Trust, and the Institute of Aging and Alzheimer’s Disease Core Center Pilot Funding Program (Dr. Roalf). University of Pennsylvania Center of Excellence for Research on Neurodegenerative Diseases (CERND). Penn Udall Center Grant: NINDS P50-NS-053488.

Compliance with ethical standards

Ethical standards

This study complies with the ethical standards set forth by the AMA. This data is original, has not previously been published, nor is it under consideration for publication elsewhere. All authors listed on this manuscript have significantly contributed to the implementation, analysis and/or drafting of this manuscript.

Conflicts of interest

The authors have no conflicts of interest.

Supplementary material

415_2018_8841_MOESM1_ESM.docx (1.3 mb)
Supplementary material 1 (DOCX 1329 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • David R. Roalf
    • 1
  • Petra Rupert
    • 1
  • Dawn Mechanic-Hamilton
    • 3
  • Laura Brennan
    • 6
  • John E. Duda
    • 2
    • 3
  • Daniel Weintraub
    • 1
    • 2
    • 3
    • 4
  • John Q. Trojanowski
    • 2
    • 3
    • 4
    • 5
  • David Wolk
    • 3
  • Paul J. Moberg
    • 1
    • 3
  1. 1.Neuropsychiatry Section, Department of Psychiatry, 10th Floor, Gates Building, Hospital of the University of PennsylvaniaUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaUSA
  2. 2.Parkinson’s Disease Research, Education and Clinical Center (PADRECC)Corporal Michael J. Crescenz VA Medical CenterPhiladelphiaUSA
  3. 3.Department of NeurologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaUSA
  4. 4.Udall Center for Parkinson’s ResearchUniversity of Pennsylvania School of MedicinePhiladelphiaUSA
  5. 5.Department of Pathology and Laboratory MedicineUniversity of Pennsylvania School of MedicinePhiladelphiaUSA
  6. 6.Department of NeurologyThomas Jefferson University HospitalPhiladelphiaUSA

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