On Friday 10th February last year, our whole department was called in to an emergency meeting to be told that our building would be closing on the following Monday, for at least two years. Up until this point, my research hadn’t been confined to a particular building, as I had conducted much of my research with children in their schools and homes. However I had just got an EEG study up-and-running, where I would be measuring children’s brain waves using sensors placed on their heads. The equipment for this isn’t particularly portable, and needs a room with minimal electrical interference, so I would need children to come into the department to take part. At the time, we didn’t know when we would have a new lab space and when we’d be able to start seeing children for the study.
What do you do when your research is suddenly not possible? For me, there was an obvious solution. I had a dataset that I had collected as a new PhD student between 2012 and 2013, with my supervisor, Liz Pellicano, which looked at how we measure children’s sensitivity to visual information. With the help of Rebecca McMillin and Janina Brede (two wonderful former undergraduate placement students at CRAE), I had seen 70 children between the ages of 6 and 9 years and 19 adults, and had asked them to judge differences in speed between sets of moving dots. Everyone completed this task 3 times, so that we could compare different methods used to find their ‘thresholds’ (the smallest differences in speed that each person could reliably discriminate).
This dataset had been sitting patiently in my file-drawer ever since. I was convinced that the research question was important. As a PhD student suddenly confronted with the confusing world of psychophysics, I didn’t know which method was best to use with children as there wasn’t much guidance out there. We know that various methods give reliable threshold estimates in adults, but children behave very differently. If children lose attention (which is understandable when we ask them to make the same judgments again and again) and make guesses on some trials, then this could lead us into mistakenly thinking that their thresholds are higher than they really are. And this is important, because we want to be sure that age-related changes in threshold estimates reflect real changes in sensitivity. I figured that if I had wanted to know about this before starting my own studies with children, there probably would be others wondering the same.
However, at the same time, I was also starting studies on how autistic children perceive motion information, and this always felt a bit more exciting and time-pressured, as autism research proceeds at a very rapid rate. I also didn’t know exactly what to do with my dataset. I knew that I should probably supplement the experimental data with simulated data to be able to see how lapses in attention can throw off the threshold estimates, but I didn’t quite know where to start. In the end, I decided not to include the study in my PhD thesis. Almost every year since, I have dipped into the dataset and worked out where I left off, before getting caught up in other projects.
The departmental building closure provided the impetus for me to finish the project, with almost three months of thinking and writing time. I teamed up with Pete Jones and Tessa Dekker from the Child Vision Lab at the UCL Institute of Ophthalmology, who helped me get the simulations off-the-ground. Interestingly, we found that the procedure used did affect the threshold estimates obtained – and that some procedures were more affected by lapses in attention than others.
A year on from the building closure, the study has just been accepted for publication (preprint here), and the department is about to move to a long-term-temporary location while our long-term-permanent location gets rebuilt. I was able to get going with my EEG study by the May half-term, seeing 100 children over a very busy summer. If the building hadn’t closed, I’m sure my old dataset would still be in my file-drawer, which would have been a huge waste – not only in terms of the time taken to collect the data, but also the time volunteered by the children and the schools who took part. And now I'm enjoying a sense of calm having cleared my research backlog (at least for the time being).
Manning, C., Jones, P. R., Dekker, T. M. & Pellicano, E. (in press). Psychophysics with children: Investigating the effects of attentional lapses on threshold estimates. Attention, Perception & Psychophysics.
Lecturer at University of Reading researching visual development, sensory processing, autism and dyslexia