Dr. John McDonald, SFU Psychology's CRC in Cognitive Neuroscience, shows strength in collaboration, mentorship, and innovation.

Psychology

Faculty Research Profile: Dr. John McDonald, Psychology

May 20, 2016
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Psychology’s Dr. John McDonald is SFU’s Canada Research Chair in Cognitive Neuroscience and he’s written widely on visual, auditory, and spatial sensory perception, processing and attention. With his research team, McDonald also recently published important new research on working memory capacity. Earning his BA in Geography and Psychology from SFU in 1993, McDonald went on to do an MA and PhD in Psychology at University of British Columbia in 1996 and 1999 but says a career in academia was never a part of his original post-secondary plan. He initially wanted to be an architect, having enjoyed drawing and drafting early on in his education. His career goals shifted over the first few years of his undergraduate training, and he eventually focused on Psychology and temporarily set his sights on a career in statistical consulting.

McDonald credits (then) graduate student, Ted Alter, and Psychology’s Dr. Ray Koopman for the shift towards Psychology. “I was hired to be [Koopman’s] teaching assistant for one course and I was really honoured and excited. He taught me to think very clearly and to formulate solid arguments, and nowadays I think these are essential skills in research.”

McDonald says his research career didn’t really take shape until he was introduced to the science of psychology through volunteering in research labs.  “One day, I summoned up enough courage to knock on the door of Dr. Richard Wright’s Vision Lab. During one of our first meetings, Dr. Wright told me about some cool reaction-time experiments on attention, and I was totally fascinated.” With some intro-level computer programming skills, McDonald helped program and run experiments in Dr. Wright’s lab and says the experience was transformative: “This was really my first experience with science: I learned that researchers could formulate some hypotheses, make some predictions, design some experiments to test those predictions, and see what happens. Perhaps more importantly, I learned that it was fun!”

Out of those experiences in the Vision Lab, McDonald says he was introduced and became focused on research in Cognitive Neuroscience. Declining offers to go to graduate school in Quantitative Psychology, McDonald opted to work with Dr. Lawrence Ward at UBC, who specialized in psychophysics and whose research stream included studies on attention. After attaining some electroencephalographic (EEG) equipment, McDonald says they started to record brain electricity in some of their experiments and notes there was “no turning back from that point.”

McDonald’s C.V. shows an extensive publication track record co-publications and demonstrates strength in collaborative research. He credits the efforts of former mentors, students and research teams for the success of several papers. Although, he notes humorously, not all article submissions were successful at first: “As a post-doc, I published a paper in the journal Nature with Dr. Steve Hillyard, a world-renowned leader in the field (McDonald, Teder-Sälejärvi & Hillyard, 2000). That paper was rejected initially, but I managed to convince the editor to consider a revised manuscript. I wore that initial rejection letter as a badge of honour (quite literally; I had a sign on my back that read, “Nature Reject”), but I was delighted when the paper was accepted. That study showed that sounds in our environment can affect how well we see. Fourteen years later, we figured out why that happens: the sounds actually activate the visual part of cortex and prime it to process visual input (McDonald, Störmer, Martinez, & Hillyard, 2013).” 

Two projects McDonald says were memorable and rewarded were strong collaborations with former students and fellow researchers.  One study, published with former student Dr. Clayton Hickey and long-time mentor Dr. Vince Di Lollo, uncovered a specific part of the EEG (what researchers call a component) that appears to correspond with the suppression of potentially distracting visual stimuli. “My team set out to study what happens when people attend to visual objects of interest, but we quickly became more interested in figuring out what happens when people try to ignore irrelevant objects. We noticed that such irrelevant objects tend to elicit an electrical brain response that we eventually labeled the distractor positivity, or PD.” McDonald says researchers now use the PD to see if people can ignore visual distractors under various conditions, and recent results from another lab show that individuals with ADHD have a “PD deficit – a specific problem in ignoring salient visual distractors”. Another project, headed by former student, Dr. Jessica Green, utilized a new “beamforming” technique for estimating the neural sources of the scalp-recorded EEG: “Dr. Green and I used the beamformer technique to track brain activity associated with attentional preparation from early sensory cortices, through partietal lobes, up to frontal cortex, and back again.” McDonald goes on to say that in their experiments, he and Dr. Green “accounted for nearly all (93%) of the variability in perceptual performance with their beamformer-based brain activity measures: more activity in the right brain area at the right time translated into more accurate visual perception.”

McDonald's PhD student, John Gaspar, places 128 electrodes into a cap. The electrodes will pick up tiny changes in the wearer's brain activity.

McDonald’s most recently published paper on distraction and visual working memory capacity  comes out of a study headed by John Gaspar and Greg Christie, two PhD students in the Electrophysiology Lab. McDonald says their work aimed at studying visual short-term memory and began with the relatively simple question, why do some individuals remember more items than others? “On average, people can hold about 3 or 4 visual objects in memory for short periods of time,” he says, “Memory researchers have long hypothesized that individual differences in memory capacity are related to attentional capabilities on the one hand and are predictive of many other cognitive abilities (like intelligence) on the other. There’s pretty solid evidence that ‘high-capacity individuals’ have better attentional control in a variety of situations. We wanted to know whether high-capacity individuals were better at picking out relevant information or at ignoring irrelevant information (different aspects of attentional control). Using EEG components like the PD, our study showed that although high-capacity individuals are able to actively suppress distractors, low-capacity individuals cannot suppress them in time to prevent distractors from capturing attention.”