Internal seminar series

This Tuesday lunchtime series of seminars brings together Psychology staff, postgraduate and undergraduate students to discuss research currently underway or recently completed within the school.

19 May, 12:00 - 13:00 (PSQ A102)

Judy Edworthy: Experiments that go 'ping': Sounds, meanings, acoustic diversity, and metaphor

9 June, 12:00 - 13:00 (PSQ A102) 

Stephen Hall: Brain rhythms: where do they come from and what do they mean?

28 April, 12:00 - 13:00 (PSQ A102) *postponed*

Judy Edworthy

In recent years there has been a great deal of interest in the design and exploitation of audible alarms in the medical environment. Audible alarms are seen as a ‘good thing’ even though they cause a lot of residual problems (‘alarm fatigue’, confusion, habituation and so on).  One of the key tests of the success of any alarm or set of alarms is the ease with which they can be learned, so it is important to apply what we know about auditory cognition to their design. Two factors which underpin the ease with which alarm sounds can be learned are the degree to which the sound is a metaphor for its function, and the degree of acoustic variability within the set of sounds to be learned. In this talk I will present the results of some studies which have been investigating the interactions between these two factors as learning progresses, the problems involved in trying to operationalise both metaphor and acoustic variability, and the implications of the findings in terms of designing alarms for the medical world in the future. During the talk I will also demonstrate what can happen when people design alarms without consulting me first, and how I intend to ensure that that doesn’t happen again.

Ian HowardCentre for Robotics and Neural Systems, Plymouth University

Past and future actions influence motor learning.

In ball sports, the role of backswing and follow-through are both considered important for generating a good shot, even though they play no direct role in hitting the ball. Here we demonstrate the scientific basis of both of these phenomena by showing that immediate past and future movements affect the learning and recall of motor memories during skill acquisition.

It is well know that when human participants make movements whilst subject to opposing dynamic force fields that change randomly between subsequent movements, substantial motor interference occurs and neither force field is learned. However when additional information in form of a contextual cue is available, this can lead to a reduction in motor interference and enable learning of both opposing force fields. Such 'interference' paradigms therefore provide an effective means to evaluate different contextual influences on motor learning.

Here we first discuss results from a set of experiments that investigated the effect of immediate past movement on dynamic learning using an interference paradigm implemented on a vBOT robotic device.  This study involved participants making two-part movements. The first part constituted a contextual movement that was predictive of the opposing dynamics experienced in the second part. It was found that such recent immediate past movement provided a very strong source of contextual information that critically affected the subsequent movement and enabled both opposing dynamics to be learned. However the effect died away rapidly as the dwell time between the two movements parts increased towards one second.

We then discuss results from a set of experiments that investigated the corresponding effect of immediate future movement. This used a similar two-part movement paradigm. This time the second part constituted a contextual movement that was predictive of the opposing dynamics experienced in the first part and again led to a significant reduction in interference. This finding suggested that variations in the follow-through of a movement could influence the partitioning of motor learning. We hypothesised that if one of many future movements directly followed a single dynamic leaning task, each separate future direction would partition the learning in the preceding movement resulting in slower learning. In contrast, if there were only a single future movement, no such partitioning would occur, resulting in faster learning. We found that the learning rate was indeed significantly faster with a single future direction compared to multiple future directions.

Finally, we investigated if participants could simultaneously make use of two different futures and two different past movement contextual cues in the same task that required the use of all four contexts. After substantial training, participants showed strong reduction in error and increased predictive force compensation demonstrating that they had learned to compensate for the force fields in all four contexts.

Overall our results suggest that there is a critical period both before and after the current movement that determines motor memory activation and controls learning.

This work was carried out in collaboration with David Franklin, Daniel Wolpert and James Ingram. Financial support for Ian Howard was provided by The Wellcome Trust and Plymouth University.

Previous talks will go here when there are some to list.