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Jeffrey R. Nicol Ph.D.
Assistant Professor of Psychology
B.A., University of Western Ontario
B.Sc., Trent University
Ph.D., McMaster
Dr. Nicol's Website:
http://web.me.com/jeffnicol/Home/Welcome.html
The idea that our knowledge about the world
influences how we think about, and interpret life experiences seems
intuitive. However, many people would likely be surprised to learn that our
knowledge of the world also influences how we perceive the events and
objects in our surroundings. In other words, perception is not simply a
veridical process in which a stimulus from our surroundings is detected by a
sensory modality (e.g., the retina for vision, or the cochlea for audition)
and then sent in an ascending, or feed-forward fashion into the brain for
further information processing. Rather, it is a bi-directional process that
also involves feedback loops that permit information to travel in a
descending fashion from the brain all the way down to the earliest stages of
perception. Perception is therefore an interaction of what is called
top-down (i.e., cognitive) and bottom-up (i.e., perceptual) processes.
As a visual psychophysicist I measure behaviour
(e.g., accuracy, response time) in visual tasks designed to investigate the
relationship between the physical stimulation and subjective perception. At
the broadest level, the experiments I conduct examine the nature of the
interaction between the two primary information-processing channels in the
visual system. One of these channels is specialized to process temporal
information and the other is specialized to process spatial information.
Interestingly, research indicates that these two systems are mutually
inhibitory. In other words, the visual system does not seem capable of
processing fine spatial and temporal details at the same time. To examine
this interaction, I compare vision at attended and unattended locations, and
present stimuli that are either emotional or neutral. Both of these factors,
attention and emotion, are believed to bias visual processing in one or the
other of the two visual channels.
Since beginning my research here at the NCRAC I have taken an interest in
investigating the effects of normal aging on these two visual channels.
Common sense tells us that visual acuity declines with age, but we do not
yet know whether these two systems are equally affected by the aging
process.
Publications:
Nicol, J.R., Watter, S., Gray, K., & Shore, D.I.
(2009). Object-based perception mediates the effect of exogenous
attention
on temporal resolution. Visual Cognition, 17, 555-573.
Nicol, J.R. & Shore, D.I. (2007).
Perceptual grouping
impairs temporal resolution. Experimental Brain
Research, 183, 141-148.
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