Motor Performance in the Context of Externally-imposed Payoffs

• Main Author: Neyedli, Heather Fern
• Other Authors: Welsh, Timothy N.
• Language: en_ca
• Published: 2013
• Subjects: Motor Control; Statistical Decision Theory; 0623
• Online Access: http://hdl.handle.net/1807/35186

Humans need to rapidly select movements that achieve their goal while avoiding negative outcomes. The processes leading to these decisions have only recently been studied. In the typical paradigm used to gain insight into the decision process, participants aim to a target circle that is overlapped by a penalty circle. They receive 100 points for hitting the target, and lose points for hitting the penalty region. Previous research has shown that participants generally behave like a rational decision maker by adapting their endpoint when the distance between the target and penalty circle and the penalty value changes (although some suboptimal selection has been noted). The overall purpose of the research reported in the present thesis was to determine if there are contexts when participants’ behaviour is suboptimal in a rapid, motor decision making tasks. Taken together, the results from four studies showed that: 1) participants require experience and feedback to aim to optimal locations; 2) participants often aimed closer to target center than optimal; and, 3) probability (represented through spatial parameters) has more influence over participant’s motor decisions than does the value of the penalty. Therefore, participants’ actions do not necessarily conform to a rational model of decision making; rather, there are consistent biases arising in the selection, planning, and execution of actions in specific contexts. These findings and conclusions can lead to a more descriptive understanding of motor decision making to provide information that is in addition to prescriptive models of rational behaviour.