Attentional deficits and postural alignment: providing new insights in the interaction between cognition and motor function after stroke.

Visuospatial neglect (VSN) is a neuropsychological cognitive condition characterized by an attention deficit to one side of the hemispace, often provoked by stroke. Patients with VSN fail to pay attention to the contralesional hemispace. Approximately 25-30% of stroke patients are confronted with VSN of which 40% still show VSN a year post-stroke. Patients with VSN need more time to recover from sensory-motor impairments, do not reach the same level of motor performance, and experience limitations in activities of daily living (ADL) as compared to post-stroke patients without VSN. However, until present it still remains unclear how VSN contributes to the poorer functional outcomes as observed in post-stroke patients. Results from studies investigating the role of VSN in motor deficits are inconsistent. Some studies show that patients with VSN have worse balance control and gait abilities as compared to patients without VSN, whereas others reject these findings. However, an important limitation of these studies is that they do not take into account the different subtypes of VSN. The different subtypes of VSN are based on the range of space in which the patients experience VSN, namely the personal (own body), peri-personal (within reach) and extra-personal space. It has been shown that these subtypes are important, as balance control and ADL improvement can differ within patients with VSN, depending on which subtype of VSN is most dominantly present. However, since research on this topic is only beginning to emerge, in-depth knowledge regarding the influence of the type of VSN on motor function is lacking. More specifically, the contribution of the different subtypes of VSN on balance control, gait, truncal function and perception of visual verticality has not yet been investigated, especially not from a biomechanical point of view. By unravelling this contribution, the mechanisms of action of VSN will become clearer. This will lead to a better understanding of the interactions between cognitive and motor impairments seen in post-stroke patients with VSN. Therefore, these insights might in turn fundamentally improve the way that the rehabilitation of post-stroke patients with VSN is currently provided. For example, to date, (spatial) cognitive and motor interventions are separately administered, and these cognitive therapies are not yet used to stimulate the motor system. Before cognitive therapies designed to enhance VSN can be recommended to stimulate motor improvements, a clear understanding and consensus regarding the influence of the subtypes of VSN on balance control, gait, truncal function and estimation of visual verticality is necessary. Within this pilot project, we aim to gain insight into the specific contribution of VSN on balance control, gait, truncal function and estimation of visual verticality, especially considering the subtypes of VSN using a biomechanical and clinical approach. Therefore, this project will deepen the understanding of the poor functional outcome that often accompanies post-stroke patients with VSN. The following research questions are considered within the current project: (I.) Do post-stroke patients with VSN have altered balance control, gait, truncal function and estimation of visual verticality compared to post-stroke patients without VSN, as measured by a combination of assessment methods? (II.) Is this dependent on the subtype of VSN? This funding will be used as seed money by providing the foundation for a novel research project which will be submitted to FWO in 2020, in which we aim to investigate the carry-over effects of VSN training on motor performance in post-stroke patients with VSN.

Keywords:GAIT ANALYSIS, REHABILITATION, NEUROPSYCHOLOGY, COGNITIVE REHABILITATION

Disciplines:Physiotherapy, Rehabilitation, Cognitive neuroscience, Neurological and neuromuscular diseases