How do we produce language and other cognitive skills, and how does normal aging alter these processes? What can familiar taboo words tell us about the relations between memory, emotion, and attention? What brain mechanisms underlie attention, memory and emotions triggered by linguistic stimuli such as taboo words? Professor MacKay's research has centered for over 30 years on relations between language and other aspects of human cognition, including not just memory, emotion, attention, but also action, music, perception, and various types of thought e.g., descriptive versus evaluative.
Special interests in language include, speech errors, derivational and inflectional morphology, stuttering, delayed auditory feedback, ambiguity and connotative meaning in language comprehension, and effects of prosody on the perception of computer compressed speech. Other special interests include relations between language perception and production, and the neural bases of language, memory, and normal cognitive aging, as discussed next. Dr. MacKay's lab is currently engaged in two lines of research directed at understanding the neural bases of language, memory, and normal cognitive aging. Our main neuroscience-linked research line concerns brain correlates of normal cognitive aging in healthy 65-90 year olds. This research has examined age-linked differences between the process of forming new connections versus the process of activating already formed connections in various contexts, including language production (especially the tip-of-the tongue phenomenon; see Burke, MacKay, Worthley & Wade, 1991), explicit versus implicit tests of memory (see MacKay & Abrams, 1996), speech perception and language comprehension (e.g., the verbal transformation effect; see MacKay, Wulf, Yin & Abrams, 1993), and very short-term memory for language, especially the effects of aging on the formation of single, theoretically-specified connections in the repetition blindness and deafness paradigms (see MacKay, Miller & Schuster, 1994). This line of research has shown that normal aging greatly impairs the formation of new connections but has relatively little impact on the process of activating already formed connections, and refines previous research on this topic where hundreds of unspecified new and old connections have been uncontrolled or free to vary. Dr. MacKay has been the PI for a major project funded by the National Institute on Aging, on the organization of cognitive processes in old age. The project addresses mechanisms underlying age-related changes in cognition, especially comprehension, memory, and the production of language and other cognitive skills, and focuses on tasks and phenomena where older adults are predicted to exhibit superior performance to young adults, unlike previous work where declines in abilities of older adults have been the main focus. The project also carries practical implications for many areas of cognitive psychology, from the everyday difficulties of older adults in learning and using new information, to teaching techniques for adult education programs. Our second line of neuroscience-related research concerns the neural bases of language and memory in normal and brain damaged humans. For example, a currently ongoing project is examining parallels between the language deficits and the memory deficits and of a famous amnesic patient (H.M.) with bilateral damage to hippocampus and amygdala. Recent publications include: MacKay, D.G., Shafto, M., Taylor, J. K., Marian, D.E., Abrams, L., & Dyer, J. (2004). Relations between emotion, memory and attention: Evidence from taboo Stroop, lexical decision, and immediate memory tasks. Memory & Cognition, 32, 474-488. MacKay, D. G. & James, L.E. (2004). Sequencing, speech production, and selective effects of aging on phonological and morphological speech errors. Psychology and Aging, 19, 93-110. MacKay, D.G., & Ahmetzanov , M, V. (2005). Emotion, memory, and attention in the taboo Stroop paradigm: An experimental analog of flashbulb memories. Psychological Science, 16, 25-32. MacKay, D.G., Hadley, C.B., & Schwartz, J.H. (2005). Relations between emotion, illusory word perception, and orthographic repetition blindness: Tests of Binding Theory. Quarterly Journal of Experimental Psychology: Human Experimental Psychology, 58A, 1514-1533. Hadley, C. B. & MacKay, D.G. (2006). Relations between emotion and memory: A further test of binding theory. Journal of Experimental Psychology: Learning, Memory and Cognition. 32, 79-88. MacKay, D. G., James, L.E., & Hadley, C. (2008). Amnesic H.M.’s performance on the Test of Language Competence: Parallel deficits in memory and sentence production. Journal of Experimental and Clinical Neuropsychology, 30, 280-300. MacKay, D.G. & Hadley, C. (2009). Supra-normal age-linked retrograde amnesia: Lessons from an older amnesic (H.M.). Hippocampus, 19, 424-45. MacKay, D.G., & James, L.E. (2009). Visual cognition in amnesic H.M.: Selective deficits on the What’s-wrong-here and Hidden-figure tasks. Journal of Experimental and Clinical Neuropsychology, 31, 769-789.MacKay, D.G. (2010). The semantics-phonology interface. In P. C. Hogan (Ed.). The Cambridge Encyclopedia of the Language Sciences (pp 757-758). Cambridge, England: Cambridge University Press.Janschewitz, K. and MacKay, D.G. (2010). Language and emotion. In P. C. Hogan (Ed.). The Cambridge Encyclopedia of the Language Sciences (pp 278-281). Cambridge, England: Cambridge University Press.MacKay, D.G. (2010). The hippocampal-language link. In P. C. Hogan (Ed.). The Cambridge Encyclopedia of the Language Sciences (pp 357-359). Cambridge, England: Cambridge University Press.