A Prospective Longitudinal Study Investigating Underlying Mechanisms of Upper Limb Somatosensory Impairments of People with Stroke

Reach High Doctoral Researcher: Dr Lisa Tedesco Triccas, Centre for Biomedical Cybernetics
Mentor: Prof. Kenneth Camilleri, Centre for Biomedical Cybernetics
Mentor: Prof. Geert Verheyden, KU leuven

Externally Funded: Reach High Scholars Programme Scheme, Ministry for Education and Employment: 254/15/13. Funding Level: EUR 198,000 (in collaboration with the University of Malta, Department of Systems and Control Engineering and Katholieke Universiteit Leuven. Total funding amount is split between CBC, SCE department and KUL, Leuven.)

Somatosensation includes exteroception (e.g. touch and pain), proprioception (e.g. position sense) and higher cognitive somatosensation (e.g. stereognosis). In a prospective longitudinal study involving 70 people with stroke which were assessed on admission to an acute ward and at two, four and six months’ post-stroke, Upper Limb (UL) stereognosis (which was associated with UL motor performance) and proprioception were more frequently impaired than tactile sensations. In the aforementioned and other, but smaller longitudinal studies on somatosensory dysfunction, only clinical measures were used. Clinical measures do not allow the investigation of underlying mechanisms of brain dysfunction. One safe, non-invasive and portable method that can be used to monitor brain activation is electroencephalography (EEG) which records the electrical activity of the brain at the scalp. It has been suggested that oscillatory EEG rhythms between sensorimotor cortices might have an important function post stroke. Furthermore, a relationship was found between severity of UL motor impairment and event-related desynchronization in the unaffected hemisphere. Thus, further longitudinal studies exploring changes in brain activation in relation to the clinical manifestation of somatosensory impairments from the early to the chronic stage are warranted. Such studies can provide a more thorough understanding of whether over-activity in the unaffected cortex is a contributor to sensorimotor impairments and subsequently, when being an independent predictor for motor outcome, provide a rationale for novel treatment options.