2005 Donald O. Hebb Distinguished Contribution Award Winner: Dr. Doreen Kimura

Doreen is a behavioural neuroscientist of great renown, whose ideas and discoveries about brain lateralization, language systems, and sex differences have influenced a generation of scientists around the world. Following a distinguished career of more than 30 years at the University of Western Ontario, Doreen has for the last 6 years been a Visiting Professor at Simon Fraser University.

Doreen Kimura was born in Winnipeg and spent most of her childhood in the small town of Neudorf, Saskatchewan. While still a teenager, Doreen spent a year as a factory worker for Electrohome, in Kitchener Ontario, assembling radio and television components by day while she completed senior matriculation courses via correspondence. The following year, she took up a post as a teacher in a one-room schoolhouse in tiny Cowan River, Manitoba. It was during this time that Doreen ventured a reply to an interesting ad that she had spotted in a magazine, an act that eventually resulted in a three-year all-expenses-paid scholarship at McGill, thus launching her career in experimental psychology.

Under the mentorship of D.O. Hebb and Brenda Milner, and during her fellowship at the Montreal Neurological Institute, Doreen’s early work had an enormous influence on the nascent field of human neuropsychology. Using a simple dichotic-listening test, Doreen probed the differences in the language and music processing capabilities of the left and right sides of the brain. She demonstrated that normal right-handed subjects have a right-ear superiority for the reception of words and numbers but a left-ear superiority for the perception of melodies, and deduced on the basis of the anatomy of the auditory projections that these superiorities must reflect the processing specializations of the contralateral hemispheres. Doreen’s early papers on this work were seized upon by researchers worldwide, leading to a proliferation of dichotic-listening experiments in normal subjects and in various clinical populations. Before the advent of modern neuroimaging, the dichotic-listening technique was recognized as one of the most useful non-invasive methods for exploring hemispheric specialization in the human brain. To this day, Doreen’s articles on cerebral lateralization are some of the most widely-cited papers in experimental psychology, and dichotic-listening is routinely used in many experimental and clinical settings.

Doreen’s work on the relationship between aphasia and apraxia during the 1970’s and 80’s caused neuropsychologists to re-examine conventional and widely-held views about language, its representation in the human brain, and its evolutionary origins. On the basis of a series of elegant experiments in both neurological patients and healthy subjects, she demonstrated a critical link between speech and the production of other complex movements. In 1993, Doreen published an important monograph, Neuromotor Mechanisms in Human Communication (Oxford University Press), which summarized her 20 years of work in this area – and offered an account of the origins of language and its representation in the brain that situates speech within a neural system that organizes the production of complex sequences of movements. By emphasizing the motor aspects of speech in addition to semantics, Doreen helped re-formulate the way in which neuropsychologists think about the neural organization of language.

In the latter third of her career, Doreen’s research has focused particularly on sex differences in cognition, and their origins in the neuroendocrine axis. Wading fearlessly into a sometimes politically-charged topic area, Doreen has catalogued numerous sex differences in cognition and has developed both proximate and evolutionary explanations for many of them. For example, Doreen has shown that aspects of spatial processing that ordinarily exhibit sex differences tend to wax and wane in synchrony with fluctuations in circulating sex steroids. She has also found that individual differences in cognitive abilities associated with sex or even sexual orientation are also associated with physiological markers of early developmental events (such as fingerprint asymmetries, which are established in utero). Doreen has further argued that at a more fundamental level, some of these sexually-differentiated patterns of abilities may have arisen from distinct characteristics of the ancestral environment, such as a division of labour between male and female hominids. Doreen’s 1999 book Sex and Cognition (MIT Press), provides a definitive account of human sex differences in brain and behaviour.

Doreen’s training of students and postdoctoral fellows has had a substantial impact on behavioural neuroscience in Canada. Throughout her career, she has supervised about 30 graduate students and 7 postdoctoral fellows. A high proportion of these individuals have gone on to research or academic positions of their own, at institutions across the country. A partial list includes: C. Mateer (UVic); E. Hampson (UWO); L. Galea (UBC); N. Watson (SFU); D. Saucier (USask); J. McGlone (Dalhousie); J. Lomas (Epidemiology, McMaster; and CEO of the Canadian Health Services Research Foundation); J. Hall (Functional Neurosurgeon, Montreal Neurological Institute); L. Leach (Baycrest Hospital, Toronto, and K. Stokes (Baycrest Hospital, Toronto). Doreen’s former students also play a major role in applied (clinical) neuropsychology. Three former PhD students now holding academic appointments also serve (or have served) as the directors or co-directors of the Clinical Neuropsychology training programs at their universities (Mateer, Hampson, McGlone). This represents nearly half of the applied neuropsychology programs in Canada. All of these individuals received intensive training in the Neuropsychology Unit that Doreen established at University Hospital in London, Ontario. In her 10 years running the unit, almost 2000 patients with neurological injuries were assessed, with another 1000 being seen for research purposes. This unit was one of the first hospital-based neuropsychology units in Canada.

Lastly, Doreen has served the broader community as an active academic spokesperson, encouraging the public to think about behaviour in terms of biology, and raising awareness of the biological factors, such as sex, that influence brain function. In founding the Society for Academic Freedom and Scholarship (SAFS), Doreen has proven to be an indefatigable and ardent defender of academic free speech.