Title page for ETD etd-09222003-213924

Type of Document

Dissertation

Author

Sos, Brian David

URN

etd-09222003-213924

Title

Dual Task Performance And Postural Recovery

Degree

Doctor of Philosophy

Department

Nutrition, Food, and Exercise Science, Department of

Advisory Committee

Advisor Name	Title
Tonya Toole	Committee Chair
George Weaver	Committee Member
John E. Bertram	Committee Member

Keywords

Limitations Of Human Motor Control During Postural

Date of Defense

2003-08-02

Availability

unrestricted

Abstract

The purpose of this project was to examine limitations of human motor control during postural recovery. A dual task paradigm, the Psychological Refractory Period
(PRP), was used to overload the attentional resources of a group of young (20-35 yrs.)
and older (70-85 yrs.) adults. Specifically, the intention was to identify age-related
differences associated with the selection of an appropriate rapid, discrete muscular
response concurrent to the execution of an automatic (non-attention demanding)
postural response. Subjects were required to respond as quickly and accurately to two
closely presented stimuli; a precision grip force task (HHFT) and toes-up perturbation,
respectively. Reaction time and the waveform integrals for each task were analyzed
using a 3 (SOA) x 2 (conditions) x 2 (age-groups) mixed model repeated measures
ANOVA. Participants apparently restructured the task requirements so posture could
be equilibrated, but at a cost of reduced speed and accuracy of the primary task. Also,
MLR and LLR amplitudes were greater as the SOA shortened. Data suggest that young
and elderly grouped the griping response with the APR. The primary stimulus
appeared to be a primer to prepare both responses for the platform rotation trigger. It
was concluded that postural recovery is attentionally demanding. Moreover, this study
reinforces the notion that postural recovery involves feedforward as well as feedback
control mechanisms. Effects of the interference task on postural mechanisms may
depend upon the underlying mechanisms of motor control rather than sensory
deprivation.

Files

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	BSosDiss.pdf	845.36 Kb	00:03:54	00:02:00	00:01:45	00:00:52	00:00:04
	BSosPP.pdf	66.68 Kb	00:00:18	00:00:09	00:00:08	00:00:04	< 00:00:01