Sensory -Tactile- Processing

We focus on investigating very basic aspects of touch (as well as other senses) in adults and children: single digits, simple stimulation, and modulation of relatively “basic” concepts such as touch detection, touch amplitude, and touch frequency.

Investigating behavioural aspects of touch (e.g. sensitivity) can be done using psychophysics. Generally, certain types of tasks or certain algorithms are used to find someone’s threshold. For example, how well can someone detect a stimulus, or discriminate between stimuli. Often, these findings can be related to what we know of how these stimuli are processed in the brain.

In 2012-2013, we developed a battery of tactile tasks (paper) that can be applied to children within a reasonable amount of time (40 min). In this battery, several aspects of touch are measured to obtain a lot of information about different tactile aspects. One reason for using the tasks that we use is that they, to some degree, provide information about the inhibitory system as is shown by invasive/animal studies.

Using a tactile device we apply tactile stimuli to fingertips. Image from He et al. 2021

Using the device above (or similar types) we use different tasks. In each trial, participants are presented with two choices and they have to choose one of these two choices (without interference of an examiner, and the same for each and every participant). For instance, we may present a weak stimulus on your middle finger and a strong stimulus on your index finger and ask you which of the two fingers received the strongest stimulus. We can test all sorts of things, such as tactile discrimination, or tactile detection thresholds.

These tasks form the basis of many of our sensory experiments, which we now perform in the auditory and visual domain as well. We continue to explore new approaches to do this better & faster, including using tablet-based approaches.