TY - JOUR
T1 - Repeated Spiral Drawings in Essential Tremor
T2 - a Possible Limb-Based Measure of Motor Learning
AU - Kim, Christine Y.
AU - Luo, Lan
AU - Yu, Qiping
AU - Mirallave, Ana
AU - Saunders-Pullman, Rachel
AU - Lipton, Richard B.
AU - Louis, Elan D.
AU - Pullman, Seth L.
N1 - Funding Information:
Prof Richard B. Lipton is funded by National Institutes of Health (U01NS094148-01, AG03949, 2PO1 AG003949, 5U10 NS077308, 1RO1 AG042595, K23 NS09610 and K23 AG049466).
Funding Information:
Funding This work was supported by the National Institutes of Health R01 NS042859 and R01 NS088257 (EDL), National Institutes of Health T32-NS07153 (LL), the Parkinson’s Disease Foundation (LL, SLP, QY), the Michael J. Fox Foundation for Parkinson’s Research Edmond J. Safra Fellowship (CK), and the National Institutes of Health U01NS094148-01 (RS-P and RBL) and AG03949 (RBL).
Funding Information:
Prof Seth L Pullman is funded by National Institutes of Health (R01 NS042859) and Parkinson's Disease Foundation (PG005860-31).
Funding Information:
The authors wish to thank Amelia Boehme, PhD, for her guidance and expertise with statistical analyses and interpretation.
Funding Information:
Research Associate Qiping Yu is funded by Parkinson's Disease Foundation (PG005860-31).
Publisher Copyright:
© 2018, Springer Science+Business Media, LLC, part of Springer Nature.
PY - 2019/4/15
Y1 - 2019/4/15
N2 - To investigate changes in tremor severity over repeated spiral drawings to assess whether learning deficits can be evaluated directly in a limb in essential tremor (ET). A motor learning deficit in ET, possibly mediated by cerebellar pathways, has been established in eye-blink conditioning studies, but not paradigms measuring from an affected, tremulous limb. Computerized spiral analysis captures multiple characteristics of Archimedean spirals and quantifies performance through calculated indices. Sequential spiral drawing has recently been suggested to demonstrate improvement across trials among ET subjects. One hundred and sixty-one ET and 80 age-matched control subjects drew 10 consecutive spirals on a digitizing tablet. Degree of severity (DoS), a weighted, computational score of spiral execution that takes into account spiral shape and line smoothness, previously validated against a clinical rating scale, was calculated in both groups. Tremor amplitude (Ampl), an independent index of tremor size, measured in centimeters, was also calculated. Changes in DoS and Ampl across trials were assessed using linear regression with slope evaluations. Both groups demonstrated improvement in DoS across trials, but with less improvement in the ET group compared to controls. Ampl demonstrated a tendency to worsen across trials in ET subjects. ET subjects demonstrated less improvement than controls when drawing sequential spirals, suggesting a possible motor learning deficit in ET, here captured in an affected limb. DoS improved independently of Ampl, showing that DoS and Ampl are separable motor physiologic components in ET that may be independently mediated.
AB - To investigate changes in tremor severity over repeated spiral drawings to assess whether learning deficits can be evaluated directly in a limb in essential tremor (ET). A motor learning deficit in ET, possibly mediated by cerebellar pathways, has been established in eye-blink conditioning studies, but not paradigms measuring from an affected, tremulous limb. Computerized spiral analysis captures multiple characteristics of Archimedean spirals and quantifies performance through calculated indices. Sequential spiral drawing has recently been suggested to demonstrate improvement across trials among ET subjects. One hundred and sixty-one ET and 80 age-matched control subjects drew 10 consecutive spirals on a digitizing tablet. Degree of severity (DoS), a weighted, computational score of spiral execution that takes into account spiral shape and line smoothness, previously validated against a clinical rating scale, was calculated in both groups. Tremor amplitude (Ampl), an independent index of tremor size, measured in centimeters, was also calculated. Changes in DoS and Ampl across trials were assessed using linear regression with slope evaluations. Both groups demonstrated improvement in DoS across trials, but with less improvement in the ET group compared to controls. Ampl demonstrated a tendency to worsen across trials in ET subjects. ET subjects demonstrated less improvement than controls when drawing sequential spirals, suggesting a possible motor learning deficit in ET, here captured in an affected limb. DoS improved independently of Ampl, showing that DoS and Ampl are separable motor physiologic components in ET that may be independently mediated.
KW - Cerebellum
KW - Computerized spiral analysis
KW - Essential tremor
KW - Motor learning
KW - Movement disorders
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UR - http://www.scopus.com/inward/citedby.url?scp=85053426131&partnerID=8YFLogxK
U2 - 10.1007/s12311-018-0974-x
DO - 10.1007/s12311-018-0974-x
M3 - Article
C2 - 30206795
AN - SCOPUS:85053426131
SN - 1473-4222
VL - 18
SP - 178
EP - 187
JO - Cerebellum
JF - Cerebellum
IS - 2
ER -