Wieske Van Zoest

Wieske Van Zoest will work at CIMeC for 3 years (ricercatore a tempo determinato).

Work description

Some things are easy to find, some are difficult. When you are in a hurry to find something, you often have a difficult time finding that what you were looking for, and when you are not specifically looking for anything, you often tend to come across those things you were looking for earlier. The world of search can be quite puzzling.

How do people select those things in the environment that they want to select and why is it that sometimes certain things and objects automatically draw attention and capture your eyes. In my work, my collaborators and I have discovered that search and selection performance 1) depends on the amount of time observers take to deploy attention and move their eye movements to a location; 2) does not always depend on observers’ awareness; 3) depends on whether there is a relation of symmetry between a target and surrounding elements; 4) benefits from a short-term visual memory representation, and 5) is automatically modulated by random reward feedback.

A main theme that returns in most of my work is the idea that representations of visual information change over time. For example, when observers respond quickly, salient stimuli are prioritized in processing regardless of their task relevance. However, as time passes salience degrades and the representation changes. It becomes more sophisticated as other information, such as prior knowledge and observer goals, is integrated. In effect, visual cognition occurs through change of visual representation over time.

Whereas my earlier work was mostly concerned with stages of visual selection, in the last couple of years I have also started to investigate how representational dynamics affect stages of perception and action. In the near future I hope to gain insight in the potential neurophysiological correlates that help to explain representational dynamics in visual selection.
 

Research areas

Dynamics in salience processing

The impact of stimulus-salience in visual selection is limited in time. Only when observers are quick to make a response, we find that salient objects attract attention and eye gaze. This transient impact of stimulus-salience has been demonstrated quite convincingly in the overt selection of saccadic eye movement. In current research we are looking at how these dynamics affect the specific saccade trajectory of the movement. Also, we are investigating how the time-course of stimulus-salience affects covert selection and stimulus-response compatibility. Another research direction in this domain involves looking at how and whether stimulus-salience is represented in visual short term memory.

Reward processing and eye movements

In recent years, there has been a growing interest in the role of reward in visual attention. Whereas a strategic role for reward is generally well-accepted in the field, there additionally may be an automatic and direct low-level influence of reward on visual selection. Together with Clayton Hickey, I am looking at how this latter idea may influence saccadic programming.

Current collaborations

Mieke Donk, Cognitive Psycholoy, Vrije Universiteit Amsterdam, NL
Clayton Hickey, CIMeC/ Cognitive Psycholoy, Vrije Universiteit Amsterdam, NL
Alan Kingstone, University of British Columbia, Vancouver, Canada
Stefan Van der Stigchel, Helmholtz Institute, Utrecht University, NL
Jan Theeuwes, Cognitive Psycholoy, Vrije Universiteit Amsterdam, NL
Mark van Vugt, Social Psychology, Vrije Universiteit Amsterdam, NL

Publications (the last three years)

Hickey, C., van Zoest, W. (in press).  Reward creates oculomotor salience. Current Biology.

Van Zoest, W., Kingstone, A. & Theeuwes, J. (in press). The time-course of identity-based SR-compatibility in visual search. Acta Psychologica.

Donk, M. & van Zoest, W. (2011). No control in orientation search: The effects of instruction on oculomotor selection in visual search. Vision Research, 51 (19), 2156-2166

Siebold, A., van Zoest, W. & Donk, M. (2011). Oculomotor evidence for top-cown control following the initial saccade. PLoS ONE,  6(9): e23552

van Zoest, W., & Hunt, A. R. (2011). Saccadic eye movements and perceptual judgments reveal a shared visual representation that is increasingly accurate over time. Vision Research, 51(1), 111-119

van Zoest, W. & Donk, M. (2010). Awareness of the saccade goal in oculomotor selection:  Your eyes go before you know. Consciousness and Cognition, 19(4), 861-871

van Zoest, W., Hunt, A. R. & Kingstone, A. (2010). Visual representations in cognition: It's about time. Current Directions in Psychological Science. 19(2), 116-120. 

Hickey, C., van Zoest, W. & Theeuwes, J. (2010). The time course of exogenous and endogenous control of covert attention. Experimental Brain Research. 201(4), 789-9

Hunt, A. R., van Zoest, W. & Kingstone, A. (2010). Attending to emerging  representations: The importance of task context and time of response. In A.C. Nobre & J. Coull (Eds.). Attention and Time. Oxford University Press. 

Mortier, K, van Zoest, W., Meeter, M. & Theeuwes, J. (2010). Word cues affect detection but not localization responses. Attention, Perception & Psychophysics. 72(1):65-7

Van der Stigchel, S., van Zoest, W., Theeuwes, J. & Barton, J. J. S. (2008). The influence of ‘blind’ distractors on eye movement trajectories in hemianopic vision. Journal of Cognitive Neuroscience. 20(11), 2025-2036

van Zoest, W. & Donk, M. (2008). Goal-driven modulation as a function of time in saccadic target selection. Quarterly Journal of Experimental Psychology, 61(10), 1553-1572. 

Donk, M. & van Zoest, W. (2008). Effects of salience are short-lived. Psychological Science, 19 (7), 733-739. 

van Zoest, W., Van der Stigchel, S., & Barton, J. J. S. (2008). Distractor effects on saccade trajectories: A comparison of prosaccades, antisaccades, and memory-guided saccades. Experimental Brain Research. 186 (3), 431- 424. 

Mulckhuyse, M., van Zoest, W. & Theeuwes, J. (2008). Capture of the eyes by relevant and irrelevant onsets. Experimental Brain Research. 186 (2), 225- 235.