Action & Cognition Lab
Postdoctoral position available
Job Advertisement is available on line at www.jobs.mq.edu.au - Reference #21672
PhD Scholarships available
http://www.research.mq.edu.au/students/scholarships/pages/LINGPSY_Attention
In the Action Lab we use a combination of different tools to investigate information processing as it unfolds in real time. The lab is currently equipped with an Optotrak Certus, which is an optical motion capture device that can track an individual's movements with sub-millimeter and sub-millisecond precision. We also have an Ultrasound system that can be used in conjuction with the Optotrak system to record the movements of the articulators that are otherwise out of view (e.g. the tongue). In addition, we have recently secured funding to incorporate both EEG (64-channel) and TMS systems into the lab.
The Action Lab is designed to allow researchers to use continuous measures in their investigation of cognitive processes generally. The reason for using a continuous measure in the study of human cognition is that it potentially constitutes a much richer data source than discrete measures (i.e. reaction times). Where discrete measures reflect the culmination of several stages of information processing, a continuous measure has the potential to reveal these processes as they unfold in realtime.
For example, instead of asking participants to respond by pressing a button or triggering a voicekey, we ask them to reach out and touch or grasp an object. By analyzing the kinematics of the participant's reaching response, we are able to compare several different dependent variables (e.g. peak velocity, peak acceleration, curvature and others) across different experimental conditions.
An important feature of the lab is the realtime interface between the Optotrak system and the stimulus-presentation system. This allows researchers to employ experimental designs whereby they can change the stimulus display depending upon the participant's movement position or velocity. It also allows for the use of psychophysical experiments in which stimulus properties vary during the course of an experiment as a function of various kinematic measures.
Data analysis can be done using C-Motion's Visual3D, or with custom, in-house analysis programs.
Movement trajectories from a single subject in a masked congruence priming experiment in which the task was "Is it an animal or a tool?". In the "Congruent" condition, both the masked prime and the target referred to the same target (e.g. dog [prime] - DOLPHIN [target]). In the incongruent condition, the prime and target stimuli referred to opposite categories (e.g. hammer - DOLPHIN). The greater tendency by this subject to initially point to the wrong target in the incongruent condition suggests that the processing of the prime stimulus proceeds all the way down to include the formulation of an overt motor response.
This fun little movie is meant to show how stimulus properties can be updated in realtime to reflect changes in the subject's movements. Note how the square on the screen changes location and size to reflect movements in 3D. Notice also that the color of the square changes as the velocity of the movement changes.