Project to develop a device that measures axial muscle tone in an upright human University of Idaho, Fall 2015

Principal Investigator Rajal G. Cohen, Ph.D. Assistant Professor of Psychology & Communication Studies Graduate Faculty in Human Factors Graduate Faculty in Neuroscience

The MML Team, 2015 Winner of William Reese Research Award Neuroscience Graduate Student Human Factors Graduate Student Investigating connections among cognition, action, and posture

Collaborators Bob Rinker UI Computer Science Microcontroller Device Maureen Schmitter-Edgecombe WSU Psychology Cognitive Aging Anita Vasavada WSU bioengineering Axial EMG Craig McGowan UI Biology Limb EMG Eric Wolbrecht UI Mechanical Engineering Stiffness Measurement Device Tim Cacciatore University College London Neurophysiologist

“You’re certainly a lot less fun since the operation.” Why would a psychologist/cognitive neuroscientist study action? What is a brain for? To move a body! The study of action is interdisciplinary Engineering Neuroscience Physiology Physical Therapy Psychology

Falls cause 90% of Hip fractures 40% of need for chronic care Death (leading accidental cause > age 60) Falls: the problem

Risk factors for falls Extrinsic/Ergonomic Factors Intrinsic Factors (affected by age, disease) o Postural control: Control of body mass with respect to task or environment

“Mindful movement” approaches reduce fall risk Does attention to postural alignment affect postural tone? In context Tai Chi Yoga Alexander Technique Does postural tone affect postural control?

How might postural tone be related to postural alignment? Possible factors A.Laxity B.Rigidity C.Responsiveness Experimental conditions A.Relax B.Pull up C.Lighten Up

Postural intentions affect postural alignment Neck compression was least in the “lighten up” condition and greatest in the “pull up” condition. Cohen et al, 2015 ______ * ______ Head-Shoulder Distance (cm)

Postural intentions affects postural sway _________ * ________ __ * __ Lighten Up Relax Pull Up Test Condition __ * __ AP Amplitude (m/s 2 ) _________ * ________ Lighten Up Relax Pull Up Standing postural sway was lowest in the “lighten up” condition, suggesting greater stability. Cohen et al, 2015 Test Condition Lighten Up Relax Pull Up

Postural instructions affect mobility This is only significant if outlier is removed. binomial comparisons lighten vs expected, p =.03 (or.049 if outlier is included) relax vs expected, p =.002 (or.01 if outlier is included) Test Condition Subjects with highest phase lead in each condition (N) * * Peak Torque (Nm) __ * __ Test Condition A. ________ # ________ __________ * __________ Test Condition Resistance to Rotation (Nm) Resistance to axial rotation was lowest in the “lighten up” condition, indicating greater mobility. Cohen et al, 2015

The Proposed Device We will build a device similar to this one o Fit chest harness to standing subject o Deliver small, sudden lateral force o Measure movement o Compute stiffness Integrate with o Twister frame o Existing software Make it moveable

Other tools: Electromyography (EMG) Since our hypothesis is related to muscle activity, we will measure it Hypothesis Instructed changes to head/neck/back will influence leg muscles

Thanks!