The sensori-neural proceses underlying our ability to localize, track, and interact with elements of our environment, and to effectively navigate through it, are crucial attributes of daily life. These are fundamental tasks of the nervous system that depend upon the integration of multiple sensory inputs to control spatial behaviors, including such simple ones as orienting towards objects of interest and walking or driving home after work. The overall goal of our research is to understand how the brain integrates sensory input from the outside world (vision and audition) with the internal senses (vestibular and somatosensory) to achieve accurate spatial perceptions, and how they coordinate behaviors (eye, head and postural movements) that allow us to orient towards and interact with external objects as well as navigate through a cluttered world. An equally important aspect is how plastic neural mechanisms are utilized to register errors and in turn adaptively adjust performance in order to maintain proper spatial calibration across sensory modalities and the behaviors they influence. Finally, an important translational concern is the neural degeneration that accompanies natural aging as well as pathology, and the functional ramifications within sensory, cognitive, and motor systems underlying spatial orientation.

Current interests center on several intriguing problems. One is directed toward understanding how the brain utilizes auditory and visual information about target location and motion in order to maintain accurate and congruent spatial calibration across modalities, as assessed through different forms of orienting movements (pointing). These include visually guided manual pointing by laser joystick, and more natural gaze (eye and head) pointing. Since gaze shifts activate vestibular reflexes (vestibulo-ocular and –collic reflexes: VOR and VCR) as well as somatosensory feedback from the neck, we are studying how the senses interact with each other and with volitional and reflex motor control. We are also investigating the important challenges of spatial memory when targets are transient, as occurs frequently in nature. Finally, we remain interested in how spatial sensory modalities are plastically co-calibrated by cross-sensory experience—an essential feature in preserving proper spatial behavior over a lifetime. A second area of research focuses on how vestibular inputs during both angular (from the semicircular canals) and linear (from the otoliths) head motion interact with each other given an intriguing limitation in the physics of the linear form (Einstein's equivalency principle). As biological linear accelerometers, the otolith organs cannot readily distinguish accelerations due to head tilt (relative to gravity) from those arising during translational (as opposed to angular) motion, and yet relevant behaviors and perceptions associated with these two forms of motion differ greatly. We are characterizing the compromised but fascinating solutions that have evolved to help resolve (albeit imperfectly) this sensory ambiguity. Our research environment is broad and translational in character, and benefits from a collegiate and multi-disciplinary group of faculty working on these problems.

Razavi, B., O’Neill, W.E. and Paige, G.D. Both Interaural and Spectral Cues Impact Sound Localization in Azimuth. Proc.IEEE EMBS, 2nd International Conf. on  Neural Engineering, p 587-590, 2005

Barnes, G.R. and Paige, G.D. 2004, Anticipatory VOR Suppression Induced by Visual and Non-Visual Stimuli in Humans. J. Neurophysiol. 92: 1501-1511.

Zwiers, M., Van Opstal, J., and Paige, G.D . 2003, Plasticity in Human Sound Localization Induced by Compressed Spatial Vision. Nat. Neurosci. 6: 175-181.

Paige, G.D. 2002, Otolith Function: Basis for Modern Testing. Ann. NY Acad of Sci, 956 : 314-323.

Paige, G.D. , Seidman, S.H. 1999, Characteristics of the VOR in response to linear acceleration. Ann. NY Acad of Sci., 871 :123-35.

Seidman, S.H., Paige, G.D. and Tomko, D.L. 1999, Adaptive Plasticity in the Naso-Occipital Linear Vestibuloocular Reflex. Exp. Brain Res., 125 :485-494.

Paige, G.D. , Telford , L., Seidman, S.H. and Barnes, G.R. 1998, The Human Vestibulo-Ocular Reflex and its Interactions with Vision and Fixation Distance During Linear and Angular Head Movement. J. Neurophysiol., 80 : 2391-2404.

Telford , L., Seidman, S.H., and Paige, G.D. 1997, Dynamics of Squirrel Monkey Linear Vestibuloocular Reflex and Interactions with Fixation Distance. J. Neurophysiol., 78 : 1775-1790.