In our every day life, our brain is constantly bombarded with all kinds of sensory information about ourselves and the environment surrounding us.  Most of it gets simply filtered out as irrelevant.  But depending on our goal of the moment, we choose to examine the source of some of those sensory inputs.  We then very easily, orient our line of sight by simply moving our eyes and head toward the object of our interest.  We perform this simple movement precisely and accurately thousands of times daily.  Even the slightest error gets corrected almost instantaneously.  Yet, despite the fact that we can do this almost effortlessly, such coordinated orienting behavior requires complex computations.  Several areas of the brain are involved in the process of locating a target, calculating its relative position and then planning and executing the required head and eye movement.  Our research is part of the big “effort” to understanding how these areas interact and influence each other.  Our work focuses mainly on the motor aspect of these processes.  Using psychophysical and physiological techniques, we study the neural mechanisms and the computations necessary to produce visually cued coordinated eye and head movements.

Quessy S., Freedman E.G.  Electrical stimulation of the paramedian reticular formation: I.   Characteristics of evoked head movements.  Soc. Neurosci. Abstr. 28 2002.

Freedman E.G., Quessy S.  Electrical stimulation of the paramedian reticular formation: II  Testing a gaze control hypothesis.  Soc. Neurosci. Abstr. 28 2002.

Lee D., Quessy S.  Scene familiarity facilitates visual search in monkeys.  Vision Sciences Society Abstract.  2002.

Quessy S., Farrell R.C., Lee D.  Neuronal activity in the supplementary motor area and the primary motor cortex during learning of movement sequences.  Soc. Neurosci. Abstr. 27, 2001.

Lee D., Quessy S.  Spike synchronization in the supplementary motor area and the primary motor cortex during sequence learning.  Soc. Neurosci. Abstr. 27, 2001.

Quessy S., Sweat A.J., Stanford, T.R., Stein, B.E.  The influence of stimulus intensity and timing on the response of multisensory neurons in the superior colliculus: comparison to a model’s prediction.  Soc. Neurosci. Abstr. 26, 2000.

Nozawa G., Stanford T.R., Vaughan J.W., Quessy S., Kadunce D., and Stein B.E.  A factorial approach to modeling multisensory integration in the superior colliculus.  Soc. Neurosci. Abstr. 23: 451, 1997.

Ptito M., Bouchard P., Lepore F., Quessy S., Di Stefano M., Guillemot JP.  Binocular interactions and visual acuity loss in esotropic cats.  Canadian Journal of Physiology & Pharmacology. 73(9):1398-405, 1995 Sep.

Di Stefano M., Ptito M., Quessy S., Lepore F., Guillemot JP.  Receptive field properties of areas 17-18 neurons in strabismic cats with the early section of the optic chiasm.  Journal fur Hirnforschung. 36(2):277-81, 1995.