Thursday, 16 February 2012

Learning a coordinated rhythmic movement with task-appropriate coordination feedback

Augmented feedback is crucial for learning in coordination tasks. This is because the inherent feedback is not often perceptually accessible if the rhythm is not 0° or 180° and must be learnt. It could be argued that some methods of augmented feedback used in learning 90° transform the task from a coordination one and so any data collected may not actually measure the learning of coordination. Therefore this paper looks at using a neutral colour cue as an augmented feedback technique so this does not occur. A green colour indicates to the participant that they are achieving the correct rhythm. This method has been developed because:
1. The relative motions involved are entirely independent of colour
2. Colour has no effect on movement stability in a coordinated rhythmic movement task
Therefore this method of feedback can drive learning without altering the informational content of the task - and it is more likely performance that the study is supposed to be measuring is actually being measured.

There were two groups:
1: 5 participants receiving the colour cue feedback
2: 5 participants receiving no feedback

The groups were balanced down to participants' baseline performance at 90°.

The neutral colour cue was successful when used as the augmented feedback system. Improvement only occured in the group that received the feedback - these participants significantly improved their ability to maintain a 90° rhythm. This did not generalise to 0° or 180° which are stable rhythms and so should not require feedback to achieve, further supporting the use of the neutral colour cue.

This study makes the point that the perception task should be the critically important component in learning the 90° rhythm. The colour cue feedback mechanism was developed in order to make this the case. Using this method, the information processed by the participant is not altered from being visual. This means that the results are more likely to be measuring learning coordination through visual perception rather than transforming the information available for learning to take place.


WILSON, A. D., SNAPP-CHILDS, W., COATS, R. & BINGHAM, G. P. 2010. Learning a coordinated rhythmic movement with task-appropriate coordination feedback. Exp Brain Res, 205, 513-20.

Life in the Lab, 16th Feb 2012

Lots going on in the lab just now, and most of it seemed to cross my desk today.

1. Jack's having a lot of success recruiting older adults for his learning study. This was always going to be the tricky bit of his Master's and his recruitment plan is really paying off.

2. Dan's pilot data for the VNS study is rolling in; not sure what, if anything is going on yet but it's nice to see the numbers to start figuring it out!

Third year research project groups
3. Met with the throwing group to finally start organising data collection; we move the target into the gym tomorrow and do pilot data collection and testing on Monday.

4. The group looking at the timed up-and-go task in older adults are all ready to roll; I will have some analysed data for them tomorrow from the piloting and we're just waiting to hear back about participant recruitment.

5. The coordination group are collecting data on the unimanual learning study and the whacky perturbation study which just might be working.

I have a paper coming my way for final comments with some great older adult learning data, plus a transfer of learning data set from IU which will make a great complement to Jack's first study. I have one super secret plan ticking along nicely, and another one in the works; plus I'm this close to having time to write up the throwing data from last year.Our second lab meeting tomorrow, Laura from Sarah's lab will present some of her work with spinal cord patients.

In other project news, young Elliott is working on his prehension and is starting to get the hang of it!

Cortical excitability increases over time awake

Today I read an interesting article which will shed doubt on all of science. I read today that the cortex generally becomes more aroused as time awake increases. So, the longer you go without sleep the more excitable your brain is, especially the frontal cortex.

What does this mean for science? Well science is the collection of knowledge acquired in various ways, a lot of which comes from experiments involving human subjects. I would almost be willing to bet that 99% of experiments using human participants have worked around the participants schedule and recruited them whenever. So for example, participant A in group A was tested at 7am (awake for 2/3 hours maybe?) and participant B in group B was tested at 4pm (awake for 8/9 hours maybe?).

Why does cortical excitability cause problems? Well, the longer you stay awake the more likely you are to have hallucinations and staying awake for a long time also reduces depressive symptoms. These signs show that the brain undergoes changes the longer you are awake. So the brain of participant A and participant B are naturally different due to different levels of being awake.

Should sleep wake cycle become a demographic question used when recruiting? Probably yes - Will it? Probably not. Why not? well if we researchers worked around our own schedule we would never have volunteers. The best we can do is try to balance groups in the same way we would balance baseline ability. Try.

But yes, this does make me wonder about science as a whole - how many imaging studies have taken data from a large sample without considering this new and scary fact? (maybe in the same way they didn’t look at caffeine baseline? - that’s a whole other kettle though).


Thursday, 9 February 2012

Determining Centre of Mass

As part of the 'timed up and go' test participants will have a marker attached to their centre of mass in order to collect data on factors such as jerk and postural sway. The centre of mass is described as a balance point of an object (Gambino et al, 2006). However before we can do this we need to determine where abouts on the body the centre of mass will be. According to Gambino et al (2006) a person's centre of mass is just below the belly button, which is nearly the geometric centre of a person. In a trial run of our experiment we were placing the marker slightly above the participant's belly button so it is possible that the data we collected maybe be inaccurate as this could have been the wrong positioning for their centre of mass.

Gambino et al (2006) concluded that a female's centre of mass is slightly lower than a males centre of mass. Unfortunately we would not be able to perform the test they did to collect these results as we are working with the frail elderly. The test they completed involved lying on beams in order to record the weight and height of each participant. There is the possibility of an injury and this involves the use of a large amount of equipment.

According to McGinnis (2005) a person's centre of mass is estimated at between 55 and 57% of their height in the anatomical position. Similarly, McGinnis (2005) identifies that a females centre of mass will be slightly lower than a males centre of mass as a result of larger pelvic girdles and narrower shoulders. This way of calculating the centre of mass would be easier to carry out as it requires little of the participants and only a small amount of equipment. If the measurements are not carried out then at least we now have a better understanding of where the centre of mass is on the human body.


Gambino,S, Mirochnik, M and Schechter S. (2006) The Physics Factbook.
McGinnis, P.M. (2005) Biomechanics of sport and exercise. Human Kinetics. pp 133.

Wednesday, 8 February 2012

The influence of augmented feedback and prior learning on the acquisition of a new bimanual coordination pattern

This paper focuses on the affects of two variables when learning a new bimanual coordination pattern; previous experiences and augmented feedback techniques. The main aim of this study is to acquire the new coordination pattern 135˚ relative phase.

Two different types of augmented feedback were compared, visual pursuit tracking and terminal feedback. Terminal augmented feedback consists of a static target lissajous figure combined with actual movement after each trial. Pursuit tracking consists of a static trace of the target lissajous, a dynamic trace of the learner’s movement during the trials and a target moving around the lissajous figure in time with the auditory metronome of 1Hz.

Participants practiced either 90˚ or 135˚ relative phase in two learning sessions and were randomly assigned to a group:

Sessions one and two:
Group 1 – practiced 90˚ relative phase with pursuit tracking
Group 2 – practiced 135˚ relative phase with pursuit tracking
Group 3 – practiced 90˚ relative phase with terminal feedback
Group 4 – practiced 135˚ relative phase with terminal feedback

In session three all four groups performed 30 trials of 135˚ lasting 20 seconds using the same feedback as in previous sessions.

Participants grasped two linear sliding devices parallel to the table and displacements were calculated. Two monitors were used to display the feedback depending on which group you were in.

Generally speaking when trying to perform a novel task most people are biased towards anti phase 180˚. In this case the groups that practiced the 90˚ pattern performed the transfer 135˚ pattern more poorly and were strongly biased towards the newly learned 90˚ pattern. During transfer the pursuit tracking groups performed with a higher mean relative phase (129.6) than the terminal feedback groups (114.9). Following two sessions of practice 90˚ pattern, performance of the transfer pattern was facilitated by pursuit tracking to a much greater extent than terminal feedback. It was suggested that pursuit tracking feedback encouraged the learner to focus on matching the lissajous figures rather than their moving limbs. This supports Wulf and Prinz (2001) who stated that performance and learning benefits if the learner focuses on the environmental effects rather than the movement itself.

WULF, G., & W. PRINZ. 2001. Directing attention to movement effects enhances learning: A review. Psychonomic bulletin & review. 8, pp. 648-660.

HURLEY, S.R., & T.D. LEE. 2006. The influence of augmented feedback and prior learning on the acquisition of a new bimanual coordination pattern. Human movement science. 25, pp.339-348.

Tuesday, 7 February 2012

Pilot data collection, TUG

For the "up and go" research into older adults, this week some preliminary data was colleceted on a group of 6 university students aged between 20-21. The pilot data was run to check that the set up of the experiment were suitable for the results to be obtained, to see any potential problems that could arise during the actual data collection, and to gather any feedback from the participants. The test was set up as it will be on the day; a line with a lentgh of 3 metres was set out, with a marker as an indicator of where to walk to at one end, and a chair at the other. The markers that collect the data were also set up appropriately, at 50cm from the ctart of the course, and 50cm from the end of the course, to detect what was happening in each segment of the walk. The participants also have a marker attatched to the using a velcro belt, which is place in the approxiate area of their centre of mass. The data was recorded using a programme specifically designed for this experiment, and the data collected was sent straight to a loptop where results can be formatted and analysed.
The participants were all walked through the test, and then given a chance for a practice run. Each participant did 3 runs of 4 different tests. The first was to get up from a sitting position, walk to the marker, turn, walk back to the chair and sit - they then had to repeat this for the second test, but had to do so whilst holding a glass of water. The third condition was to get up from the chair, walk to the marker, which was now covered by an obstacle, walk around that, walk back to the chair and sit back down. The fourth coniditon was the same yet holding a glass of water.
Some of the issues that became apparant during the test were:

1) people adopted different positions when sitting in the chair prior to starting the test, e.g. crossing their legs leaving only one foot on the ground.

2) People talking throughout the test lead them to turn to the person they were having a conversation with, which could effect the way the data is read from the marker.

3) At times, the marker became loose, and detatched from the belt.

4) They completed 12 different trials per person, and whilst it was no problem for them, for
a frail, elderly adult, this could be exhausting.

5) In the feedback, one participant felt the test was 'degrading' due to being attatched to a wire.

All of these issues need to be resolved to the best they can be, without affecting the results of the data collection or inhibiting the findings of the research.

VSS abstract accepted

Congratulations to Jack for getting his poster accepted at this year's Annual Meeting of the Vision Sciences Society in Naples, FL, May 11-16.

Perceptual learning of bimanual coordinated rhythmic movements: Information matters more than movements
Jack Leech & Andrew D. Wilson

Prior to training, only two coordinated rhythmic movements are stable: 0° and 180°. Other coordinations (e.g. 90°) must be learned. This pattern emerges from a task dynamic in which relative phase is perceived as the relative direction of motion, modified by the relative speed (Bingham, 2004). People can learn how to move at 90° but this entails learning to use a different information variable (relative position; Wilson & Bingham, 2008). Learning a novel coordination requires feedback; typically this feedback is presented in the form of a transformed display such as a Lissajous plot. This display removes relative direction as a source of information about relative phase, and as a result allows people to move at any required coordination with a minimum of practice – all coordinations become equally easy.  Wilson et al (2010) developed a second form of feedback, coordination feedback, which also drives learning but without altering the information available for relative phase. This study directly compared the two feedback methods. 12 subjects (aged 18-27, M=21) learned to move bimanually at 90° using either Lissajous (N=6) or coordination (N=6) feedback. We tested coordination stability with both displays in baseline, post training and retention sessions, with baseline and post training separated by 5 training sessions. Results indicated that both feedback methods are valid methods that facilitate learning. However there was no transfer of this learning between the feedback methods, confirming that the feedback methods provide different perceptual information and that perceptual learning underpins the improvements in movement stability. The two feedback methods create fundamentally different task dynamics that are informationally distinct from one another, and must be treated as such.

Wednesday, 1 February 2012

Newton International Fellowships

If you are looking for a post-doc opportunity in the UK, and are trained in perception, action or embodied cognition type research, then this is an excellent funding stream and I would be very interested in hearing from you to come and work in my lab. Please feel free to contact me if interested, and spread the word to other interested parties!

A new round of Newton International Fellowships - an initiative to fund research collaborations and improve links between UK and overseas researchers - has now opened.

The Newton International Fellowships are funded by the British Academy and the Royal Society and aim to attract the most promising early-career post-doctoral researchers from overseas in the fields of the humanities, the natural, physical and social sciences. The Fellowships enable researchers to work for two years at a UK research institution with the aim of fostering long-term international collaborations.

Newton Fellows will receive an allowance of £24,000 to cover subsistence and up to £8,000 to cover research expenses in each year of the Fellowship. A one-off relocation allowance of up to £2,000 is also available.

In addition, Newton Fellows may be eligible for follow-up funding of up to £6,000 per annum for up to 10 years following completion of the Fellowship to support activities which will help build long term links with the UK.

The scheme is open to post-doctoral (and equivalent) early-career researchers working outside the UK who do not hold UK citizenship.

Applications are to be made via the Royal Society’s online application system which is available at The closing date for applications is Monday 16 April 2012.

Further details are available from the Newton International Fellowships website: