Segraves, Mark A., PhD



Segraves, Mark A., PhD




Office Phone





Cook Hall 2-137 Evanston


NOW accepting rotation students

Accepting rotation students

Areas of Research

Circuits and Behavior, Computational, Electrophysiology, Motor Control, Sensory Systems

Training Grants

General Motor Control Mechanisms and Disease Training Program

NU Scholar Profile

Recent Publications on PubMed

Current Research

Current Research

General Interests:
Areas of Research Focus:
1) Neural Mechanisms of Fixation Choice while Searching Natural Scenes
Major collaborator: Konrad Kording, Ph.D.
In these experiments, we use rhesus monkeys as a model to address questions concerning the cognitive control of eye movement behavior. Our overall goal is to understand how the brain controls where we look. To accomplish this, it’s important to study brain activity and behavior under conditions that approximate those in the real world. The frontal eye field (FEF) is a cortical area closely involved in the control of purposive voluntary eye movements. In prior work, we have studied activity in the FEF while monkeys looked at images of natural scenes. While the monkey searched for a target hidden in the images, the activity of FEF neurons consisted of combinations of activity related to planning upcoming eye movements, as well as activity that was sensitive to salient visual features of the image. In parallel with the development of our understanding of how the brain controls eye movements, there have been substantial advances in our understanding of the features of natural images that guide both human and monkey eye movements. These behavioral studies are at the advanced level of being able to accurately predict patterns of eye movements. The goal of our current investigations is to take advantage of these advancements in predicting patterns of eye movements in natural environments to help us understand the brain events that are responsible for this behavior. In addition to the brain recording experiments, a large part of our effort is devoted to mathematical analysis and modeling of the behavioral and neuronal data we obtain. Our ultimate goal is to provide a model that predicts the brain’s search-related activity for both artificial and natural visual environments.
2) Development and Organization of Eye Movement Maps in Mouse Superior Colliculus
Major collaborator: Jianhua Cang, Ph.D.
For this project, we are taking advantage of the vast array of genetic tools available for the mouse model to address questions related to development and organization for eye movements that are likely to be shared across species, including primates. The mammalian superior colliculus (SC) is a subcortical structure that integrates visual and other sensory information to initiate orienting movements of the eyes and head. A fundamental feature of SC organization is that the representations of sensory inputs and motor outputs are topographically arranged and aligned. While great progress has been made in understanding the development of the visual representation in the mouse SC, how the motor maps are formed and aligned with the visual map remains unknown. The goal of this project is to reveal the topographic organization for movement control in the deep layers of the SC. In addition, we are using environmental and genetic manipulations to help us to understand the factors responsible for the development of this topography.

Selected Publications

Selected Publications

Phillips AN, Segraves MA (2010) Predictive activity in macaque frontal eye field neurons during natural scene searching. J Neurophysiol 103:1238-1252.

Ratcliff R, Hasegawa YT, Hasegawa RP, Childers R, Smith PL, Segraves MA (2011) Inhibition in superior colliculus neurons in a brightness discrimination task. Neural Comput 23:1790-1820.

Fernandes HL, Stevenson IH, Phillips AN, Segraves MA, Kording KP (2014) Saliency and Saccade Encoding in the Frontal Eye Field During Natural Scene Search. Cerebral Cortex 24:3232-3245.

Ramkumar P, Fernandes H, Kording K, and Segraves M (2015) Modeling peripheral visual acuity enables discovery of gaze strategies at multiple time scales during natural scene search. Journal of Vision 15(3).

Wang L, Liu M, Segraves MA, Cang J (2015) Visual experience is required for the development of eye movement maps in the mouse superior colliculus. J. Neuroscience, In Press.