Reaching decisions: integration of action selection and action performance in learning tool use during middle childhood

Host Institution: University Medical Center Groningen

Department that hosts the PhD: Department of Human Movement Sciences

Supervisors involved: Dr. Smith, Dr. Bongers, Prof. dr. Schöner, Dr. Reinders-Messelink

Project description

This project focuses on perception-action exploration used during learning a reaching task, studied from an Ecological Approach and a Systems perspective. Perceptual learning will be studied by focusing on how the perception of affordances, the opportunities available for action, change over learning, that is how perceived reachability changes over practice. Motor learning will be studied by focusing on how the actualisation of the reaching actions changes over learning, that is, examining how the hand-end effector kinematics and use of angles in the arm and trunk change over practice. By combining knowledge from perceptual learning and motor learning, this project will provide novel insight into how the changes in affordance perception and actualisation interact during learning novel reaching tasks.  

In the experiments participants will make perceptual judgements of their maximum reaching ability and subsequently perform the reaching actions. Practice sessions will consist of repetitions of this perception-action cycle where they can freely explore the affordances available. The affordances available will be manipulated by varying the features of the environment (e.g. weight or distance of object) and abilities of the actor (e.g. weight or length of arm), thereby manipulating the opportunities available for reaching. Through these manipulations we aim to determine processes of perception-action exploration occurring at the level of the actor-environment system. The learning process will be analysed by examining affordance perception in terms of the accuracy and variability of perceptual judgments, meanwhile the affordance actualisation will be examined in terms of the variability of hand-end effector kinematics and joint angle range of motion of the reaching system. It is hypothesised that changes in perceived reachability influence the coordination of the reaching action, which in turn changes the actualisation of the reaching action and vice versa.  

The objectives of this project are: i) to establish how affordance perception and actualisation change over learning, and ii) to determine processes of perception-action exploration individuals use to discover affordances by identifying specific search strategies used during learning a reaching task. By understanding the process of perception-action exploration during learning, we can create training conditions to assist the exploration process and thereby aid the process of re-learning to perceive and act in individuals who require rehabilitation.