We would like to welcome a new member to the lab, Carli Fine. Carli received her bachelor’s degree at the University of Maryland, and was most recently a research assistant in David Brang’s Multisensory Perception Lab at the University of Michigan. Carli has done quite interesting work with electrocorticography and synesthesia in the past, and we are looking forward to having her in our lab.

Our lab went to our first, in-person post-pandemic conference: IMRF 2022 in Ulm, Germany. First, Anu Nair gave a poster on her first-year project titled “Viewed Touch Influences Tactile Detection by Altering Decision Criterion.” Luisa Raigosa-Posada gave a talk on her MVPA work with former lab student Yuqi Liu on the “Neural correlates of tactile representations in somatotopic and external reference frames.” Finally, Prof. Medina gave a talk in the final symposium of the conference, titled “(Mis)perceiving tactile location using the mirror box illusion: Examining the relationship between perceived touch and embodiment.”

We are quite excited to be part of a new collaboration with Dr. Charles Dhong, assistant professor in the Department of Material Science & Biomedical Engineering. In our new R01, titled “Creating New Tactile Sensations for Tactile Aids with Designer Materials“, Dr. Dhong will be creating new tactile materials by manipulating surfaces at the molecular level. These designer materials will then be tested to see if they can improve tactile processing in the blind. We also plan to use these materials in psychophysical experiments to understand fundamental properties of tactile processing.

Based on a collaboration with Ph.D. student Emma Beisheim-Ryan and Meg Sions in the Department of Physical Therapy, we have three new papers out on phantom limb pain.

• Beisheim, E.H., Pohlig, R.T., Hicks, G.E., Horne, J.R., Medina, J., & Sions, J.M. (2022). Mechanical Pain Sensitivity in Post-Amputation Pain. Clinical Journal of Pain, 38, 23-31.
• Beisheim, E.H., Pohlig, R.T., Medina, J., Hicks, G.E. & Sions, J.M. (2022). Body representation among adults with phantom limb pain: Results from a foot identification task. European Journal of Pain, 26, 255-269.
• Beisheim-Ryan, E.H., Hicks, G., Pohlig, R.T., Medina, J., Sions, J.M. (online ahead of print). Body image and perception among adults with and without phantom limb pain. PM&R: The Journal of Injury, Function and Rehabilitation.

At her post-doctoral position at Georgetown, our PhD alumnus Yuqi Liu has just published a fascinating paper in the Proceedings of the National Academy of Science, in which she examined action representations in individuals born without hands. It’s a very interesting paper and worth your time to read.

Where do people feel a touch when their hand is not where they see it? In the classic rubber hand illusion, people feel touch on the seen rubber hand when it is brushed in synchrony with their unseen actual hand. But does the actual hand still influence tactile perception?

Using the mirror box illusion, we found that when there was spatial mismatch between visual and proprioceptive information of hand position, the perceived location of tactile stimuli on the skin surface was systematically biased toward the proprioceptively-defined hand position compared to baseline. These results provide evidence that the actual hand position exerts influence on tactile localization, adding to past findings that information from external space affects tactile localization in somatotopic space. You can read it here.

We are delighted to welcome three new members to the lab.

Pushpita Bhattacharyya is a new PhD student who received her undergraduate degree from the University of California – San Diego. While working with Dr. V.S. Ramachandran, she examined grapheme-color synesthesia in Bengali. She plans to continue this research and expand to studying mirror-touch synesthesia.

Luisa Raigosa Posada is a new 4+1 student. She comes with a Master of Music degree in clarinet performance and a BS in Neuroscience from the University of Delaware. She will be working on neuroimaging projects – specifically using multi-voxel pattern analysis (MVPA) and representational similarity analysis (RSA) to examine multisensory integration and representations of tactile space.

Riwa Safa is a new PhD student who received her undergraduate degree from the American University of Beirut. Her previous research examined the relationship between reading direction and face perception. She is working on visuoproprioceptive integration, with a focus on evidence from individuals with stroke.

Welcome!

Our new case study has been published in Neuropsychologia. We report an individual with subcortical damage who had excellent detection of light touch on the contralesional hand. However, his tactile localization on the contralesional hand was severely impaired, with his responses clustering on the left side of his hand.

Interestingly, “side” depended on the position and orientation of his hand. Regardless of whether his hand was positioned palm-up or palm-down, his errors were always on the left side of the hand relative to the participant’s viewpoint (i.e. towards the 5th finger with palm down, towards the thumb with palm up). When the hand was turned 90 degrees, his errors were made towards the left side of the hand in a hand-centered frame of reference.

This provides strong evidence for a dissociation of tactile detection and localization, shows that body position can modulate tactile localization, and provides evidence for hand-centered representations for touch. You can read the manuscript here.

We would like to welcome two new members to the lab – Elisabetta Ambron and Anupama Nair. Elisabetta Ambron is a post-doctoral fellow who received her Ph.D. at the University of Edinburgh, and was recently a post-doc at the University of Pennsylvania. She will be studying body representations, focusing on research with brain-damaged individuals. Anupama Nair is a new graduate student who received her B.A. at St. Xavier’s College and received her M.Sc. at the University of Amsterdam. After working on synesthesia and neuroimaging at the University of Michigan and UT-Dallas, she now begins her career as a graduate student in our lab.

We are very happy to announce that we’ve been awarded with a new NSF grant! In a collaboration with Jen Semrau (Kinesiology and Applied Physiology), Hyosub Kim (Physical Therapy) and Fabrizio Sergi (Biomedical Engineering), we plan to study proprioception and multisensory integration in stroke survivors. We will also use robotics and adaptive algorithms to develop individualized rehabilitation protocols for improving sensorimotor function.