Johns Hopkins School of Medicine

Sensory and ocular motor mechanisms of human spatial perception

Our work combines investigations in normal humans and patients with disorders that affect movement of the eyes and perception of spatial orientation. A special focus has been on sensory mechanisms of spatial orientation and and how related abnormalities can be ameliorated in patients.  We use psychophysical methods, analytical models, and transcranial magnetic stimulation (TMS) to investigate brain functions related to spatial perception and ocular motor control. Our work is translational with an iterative process between the laboratory and clinic using computational modeling at the interface. Along these lines, we seek to innovate and develop quantitative methods that can be applied in both research and clinical practice. 

A key aspect of our spatial orientation is the stable perception of the world despite continuous changes in the position of our eyes, head and body. Such ‘orientation constancy’ is the prerequisite for coherent spatial perception, and when it fails the neuro-behavioral consequences can be incapacitating due to symptoms such as dizziness, sensitivity to head motion, or sudden feelings of imbalance or tilt. In our lab, we use behavioral paradigms, computational models, and TMS for functional mapping of the human temporoparietal cortex with respect to perception of spatial orientation.  We employ several techniques for noninvasive, sensitive, accurate, and low-noise quantifications of eye movements and related visuospatial functions in humans. We use similar techniques to study neural mechanisms of disorders that affect balance and spatial orientation in patients. This approach allows us to produce meaningful, applicable results that can be directly applied to advance diagnosis and treatment in clinical practice.