title: Saliency and saccade encoding in the frontal eye field during natural scene search.
abstract: The frontal eye field (FEF) plays a central role in saccade selection and execution. Using artificial stimuli, many studies have shown that the activity of neurons in the FEF is affected by both visually salient stimuli in a neuron's receptive field and upcoming saccades in a certain direction. However, the extent to which visual and motor information is represented in the FEF in the context of the cluttered natural scenes we encounter during everyday life has not been explored. Here, we model the activities of neurons in the FEF, recorded while monkeys were searching natural scenes, using both visual and saccade information. We compare the contribution of bottom-up visual saliency (based on low-level features such as brightness, orientation, and color) and saccade direction. We find that, while saliency is correlated with the activities of some neurons, this relationship is ultimately driven by activities related to movement. Although bottom-up visual saliency contributes to the choice of saccade targets, it does not appear that FEF neurons actively encode the kind of saliency posited by popular saliency map theories. Instead, our results emphasize the FEF's role in the stages of saccade planning directly related to movement generation.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Northwestern University and Rehabilitation Institute of Chicago, Chicago, IL 60611, USA PDBC, Instituto Gulbenkian de Ciência, 2780 Oeiras, Portugal Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, 2780 Oeiras, Portugal.
authors.forename: Hugo L
authors.initials: HL
authors.lastname: Fernandes
authors.affiliation: Redwood Center for Theoretical Neuroscience, University of California, Berkeley, CA 94720, USA.
authors.forename: Ian H
authors.initials: IH
authors.lastname: Stevenson
authors.affiliation: Tamagawa University, Brain Science Institute, Machida 194-8610, Japan Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Adam N
authors.initials: AN
authors.lastname: Phillips
authors.affiliation: Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Segraves
authors.affiliation: Department of Physical Medicine and Rehabilitation, Northwestern University and Rehabilitation Institute of Chicago, Chicago, IL 60611, USA Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, IL 60208, USA Department of Physiology, Northwestern University, Chicago, IL 60611, USA.
authors.forename: Konrad P
authors.initials: KP
authors.lastname: Kording
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001288:Attention / Q000502:physiology*; D005260:Female; D008253:Macaca mulatta; D008568:Memory / Q000502:physiology; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000166:cytology*; D012372:ROC Curve; D011930:Reaction Time / Q000502:physiology; D012438:Saccades / Q000502:physiology*; D014794:Visual Fields; D014796:Visual Perception / Q000502:physiology*
keywords: attention; fixation choice; generalized linear models; natural stimuli; neural data analysis; visuomotor integration