Picture of Steven Prime

Steven Prime B.A. (Honours), M.A., Ph.D Associate Professor in Cognitive Neuroscience

Office
Arts 184

Research Area(s)

  • Attention
  • Perception
  • Multisensory processing
  • Trans-saccadic perception
  • Human Factors
  • Philosophy of mind
  • Working memory
  • Sensorimotor integration

About me

I am originally from Montreal, Canada. I earned my Bachelor’s (with Honours) at Simon Fraser University (Vancouver) and then went on to earn my Masters and Doctorate degrees working with Dr. Doug Crawford in the Centre for Vision Research at York University (Toronto). After completing my PhD, I held a CIHR-funded Postdoctoral Research Fellow position in Dr. Jonathan Marotta’s laboratory at the University of Manitoba (Winnipeg). After my Postdoctorate, I was an Assistant Professor at Victoria University of Wellington (Wellington, New Zealand) before joining the Department of Psychology at the University of Saskatchewan.

I am the director of the Neurocognition & Psychophysics Laboratory. Broadly, my research is focused on the underlying cognitive and cortical processes of attention and perception. In my lab, we employ a multidisciplinary research approach combining traditional research methods from cognitive psychology and psychophysics with sophisticated eye tracking methods, computational modeling, and transcranial magnetic stimulation (TMS).

Publications

Glazebrook, C.M., Brown, K., PRIME, S.L., Passmore, S.R., & Marotta, J.J. (2020). Both reaching and grasping are impacted by temporarily induced paresthesia. Somatosensory & Motor Research, 37, 106-116

King, C. & PRIME, S.L. (2019). Auditory pitch glides influence time-to-contact judgements of visual stimuli. Experimental Brain Research, 237, 1907-1917

Bartel, S., Toews, K., Gronhovd, L., & PRIME, S.L. (2018). 'Do I know you?': Altering hairstyle affects facial recognition. Visual Cognition, 26, 149-155

Badart, P., McDowall, J., & PRIME, S.L. (2018). Multimodal sustained attention superiority in concentrative meditators compared to nonmeditators. Mindfulness, 9, 824-835

Bulloch, M.C., PRIME, S.L., & Marotta, J.J. (2015). Anticipatory gaze strategies when grasping moving objects. Experimental Brain Research, 233, 3413-3423

Tanaka, L.L., Dessing, J.C., Malik, P., PRIME, S.L., & Crawford, J.D. (2014). The effects of TMS over dorsolateral prefrontal cortex on trans-saccadic memory of multiple objects. Neuropsychologia, 63, 185-193

PRIME, S.L. & Marotta, J.J. (2013). Gaze strategies during visually-guided and memory-guided grasping. Experimental Brain Research, 225, 291-305

Lawrence, J.M., Abhari, K., PRIME, S.L., Meek, B., Desanghere, L., Baugh, L.A., & Marotta, J.J. (2011). A novel integrative method for analyzing eye and hand behaviour during reaching and grasping in an MRI environment. Behavior Research Methods, 43, 399-408

PRIME, S.L, Vesia, M., & Crawford, J.D. (2011). Cortical mechanisms for trans-saccadic memory and integration of multiple object features. Philosophical Transactions of the Royal Society B: Biological Sciences, 366, 540-553

PRIME, S.L. & Harris, L.R. (2010). Predicting the position of moving audiovisual stimuli. Experimental Brain Research, 203, 249-260

Vesia, M., PRIME, S.L., Yan, X., Sergio, L., Crawford, J.D. (2010). Specificity of human parietal saccade and reach regions during transcranial magnetic stimulation. Journal of Neuroscience, 30, 13053-13065

PRIME, S.L., Vesia, M., & Crawford, J.D. (2010). TMS over human frontal eye fields disrupts trans-saccadic memory of multiple objects. Cerebral Cortex, 20, 759-772

PRIME, S.L., Vesia, M., & Crawford, J.D. (2008). Transcranial magnetic stimulation over posterior parietal cortex disrupts trans-saccadic memory of multiple objects. Journal of Neuroscience, 28, 6938-6949

Vesia, M., Esposito, J.G., PRIME, S.L., & Klavora, P. (2008).  Correlations of selected psychomotor abilities and visuomotor skills with Dynavision performance. Perceptual and Motor Skills, 107, 14-20

PRIME, S.L., Tsotsos, L., Keith, G.P. & Crawford, J.D. (2007). Visual memory capacity in trans-saccadic integration. Experimental Brain Research, 180, 609-628

PRIME, S.L., Niemeier, M., & Crawford, J.D. (2007). Trans-saccadic memory of visual features. In L. Harris & M. Jenkins (eds.) Computational Vision in Neural and Machine Systems (pp167-182). Cambridge University Press, UK

PRIME, S.L., Niemeir, M., & Crawford, J.D. (2006). Trans-saccadic integration of visual features in a line intersection task. Experimental Brain Research, 169(4), 532-548

Richard, C.M., Wright, R.D., PRIME, S.L., Ee, C.M., Shimizu, Y., & Vavrik, J. (2002).  Effect of a concurrent auditory task on visual search performance in a driving-related image-flicker task. Human Factors, 44(1), 108-119

Teaching & Supervision

Psychology 252 Perception

Psychology 253 Introduction to Cognitive Psychology

Psychology 246 Neuropsychology

Psychology 347 Advanced Human Neuropsychology

Psychology 348 Research in Human Neuropsychology

Psychology 355 Advanced Research in Cognitive Sciences

Psychology 448/898 Attention

Research

attention brain computer interfaces cognition cognitive neuroscience multisensory processing perception transcranial magnetic stimulation

Broadly, my research is focused on the underlying cognitive and cortical processes of attention and perception. In my lab, we employ a multidisciplinary research approach combining traditional research methods from cognitive psychology and psychophysics with sophisticated eye tracking methods, computational modeling, and transcranial magnetic stimulation (TMS). My lab is currently engaged in the following research streams:

Multisensory Integration
We are studying how the brain integrates information from multiple senses to produce a coherent and more reliable perception of the world. To this end, we seek to better understand such problems as: how do the senses interact and alter each other's processing (e.g., like in the ventriloquism effect); how different information from multiple senses are integrated at different levels of the cortical processing hierarchy; and, how is the relative timing of different sensory inputs coded to maintain perception of synchrony between the senses.
Sample publication:
Prime, S.L. & Harris, L.R. (2010). Predicting the position of moving audiovisual stimuli. Experimental Brain Research, 203, 249-260

Crossmodal Attention
Our research also addresses how selective attention and processing information is affected by using multiple modalities. Sometimes directing attention to one sensory modality happens at the expense of others (e.g., talking on a cell phone while driving). Our research in this area is focused on better understanding the crossmodal links in attention and the extent to which audiory and visual attention can interact.
Sample publication:
Richard, C.M., Wright, R.D., Prime, S.L., Ee, C.M., Shimizu, Y., & Vavrik, J. (2002). Effect of a concurrent auditory task on visual search performance in a driving-related image-flicker task. Human Factors, 44, 108-119

Trans-saccadic Perception
One of the central questions in visual neuroscience is how do we perceive the visual world as a seamless and unified image despite repeatedly rapid changes in gaze. To explain, humans make about 3-5 rapid eye movements, called saccades, per second. This means that our gaze is focused on one point of a visual scene for only a short time before moving to another point on the scene. Since our visual acuity is limited to our point of gaze, we only process one small part of a visual scene effectively at a time. It follows that in order to perceive the entire visual scene as a unified image, the individual elements of a scene have to be pieced together by serially sampling these different elements using saccadic eye movements. The perceptual experience of a continuous and unified visual world from disparate gazes separated by saccades is known as trans-saccadic perception. Our research is aimed at exploring how the visual system builds an internal representation of a visual object or scene across saccades. We also seek to better understand how trans-saccadic perception might contribute to maintaining perceptual stability across saccades - i.e., the perception of a stable visual world where the location of objects are perceived to be unchanged despite their positions on the retina dramatically changing with every saccade.
Sample publication:
Prime, S.L., Vesia, M., Crawford, J.D. (2011). Cortical mechanisms for transsaccadic memory and integration of multiple object features. Philosophical Transactions of the Royal Society B: Biological Sciences, 366, 540-553