Associate Professor Steven Roodenrys
At UOW I lecture in cognitive psychology and research methods.
After completing my PhD from the University of New South Wales I worked at Sydney University on a research project on implicit learning with Prof. Robert Boakes and helped with the establishment of their new learning labs. I then moved on to hold a post-doctoral position at the University of York, working with Prof.'s Charles Hulme and Gordon Brown on a project on human short-term memory. I have been working at UOW since 1994.
Research Interests and Example Publications
Verbal short-term memory is my major area of research. The issue that I have been most interested in is how long-term memory interacts with short-term memory, particularly how long-term memory influences short-term memory. For a number of years I have been looking at how word frequency influences performance in short-term memory tasks. In a nutshell, words that you hear often are remembered better in short-term memory tasks than words that you don't hear very often. This has led to more recent research looking at the effect of other words in long-term memory on recall of the words that were presented. I have been looking at recall of words which are phonologically distinctive, in that they do not sound like many other words in English, as opposed to words that do sound similar to many words in English.
This is part of a broader issue that I find very interesting which is whether verbal short-term memory is better thought of as a specific memory system (much like any other memory system but it just happens to store words) or as part of the complex processes and mechanisms which underlie speech perception and production. Do verbal short-term memory tasks rely on a memory system that operates like other memory systems or do they have more in common with other language tasks?
Roodenrys, S. & Hinton, M. (2002) Sublexical or Lexical Effects on Serial recall of nonwords? Journal of Experimental Psychology: Learning, Memory and Cognition, 28, 29-33.
Roodenrys, S., Hulme, C., Lethbridge, A., Hinton, M. & Nimmo, L.M. (2002) Word frequency and phonological neighbourhood effects on verbal short-term memory. Journal of Experimental Psychology: Learning, Memory and Cognition, 28, 1019-1034.
Nimmo, L.M. & Roodenrys, S. (2004) Investigating the phonological similarity effect: Syllable structure and the position of common phonemes. Journal of Memory and Language, 50, 245-258.
Nimmo, L.M. & Roodenrys, S. (2005) The phonological similarity effect in serial recognition. Memory, 13, 773-784.
Attention Deficit Hyperactivity Disorder
My research in this area has been limited to supervising student research projects that have looked at possible impairments in cognitive processes in this disorder. Research from this perspective (and theorising) is beginning to concentrate on the notion that this disorder reflects impaired "executive function". One of these executive functions that I have investigated is inhibition. That is, the ability to inhibit or withhold a response to a stimulus. In the case of ADHD, these children may have trouble in preventing themselves from responding to stimuli in the environment. Normally we are able to inhibit responses like this in order to perform our current task, and our ability to do so improves throughout childhood. Children with ADHD may have an impairment in this process which makes controlling their behaviour difficult and affects their ability to learn. These effects may be more subtle, in that it is also argued that inhibition is involved in keeping distracting stimuli out of working memory, allowing the cognitive processes to operate more efficiently.
Bayliss, D.M. & Roodenrys, S. (2000) Executive processing and Attention Deficit Hyperactivity Disorder: An application of the Supervisory Attentional System. Developmental Neuropsychology, 17, 161-180.
Roodenrys, S., Koloski, N. & Grainger, J. (2001) Working memory function in Attention Deficit Hyperactivity Disordered and Reading Disabled children. British Journal of Developmental Psychology, 19, 325-338.
Roodenrys, S. (in press) Working memory function in Attention Deficit Hyperactivity Disorder in Working memory and Neurodevelopmental condition by T. Packiam Alloway & S. E. Gathercole (Eds). Hove, UK: Psychology Press.
Phonological Neighbourhood Effects in Short-term Memory and
Speech Production: Towards a Unified Account
This research will investigate the relationship between verbal short-term memory (STM) and speech production processes and seeks to elucidate the processes underlying verbal short term memory.
The traditional (non-linguistic) approach to short term memory involves its function as a record of recent past, with most models involving analogous storage systems or processes for preserving different types of material such as spoken words (verbal STM) or pictures (visual STM).
In contrast, the psycholinguistic approach views verbal STM as part of a language system, with performance on verbal STM tasks assumed to be reflective of processes designed to allow us to produce and perceive speech. From a psycholinguistic perspective, verbal STM's storage function is seen as secondary to its primary purpose as a language system and thus fundamentally different from storage systems relating to non-verbal stimuli.
Within this project a series of experiments will be undertaken involving tasks designed to tap STM and speech production processes, including accessing the speech production lexicon. The research is being undertaken with the aim of identifying the locus of phonological neighbourhood effects on serial recall and understanding how it relates to the neighbourhood effect in speech production tasks.
Since short term memory performance is linked to IQ and language ability, understanding how memory and language interact will enhance understanding of language acquisition and thus has implications for language instruction in areas such as second language acquisition, developmental language disabilities and language impairments resultant from acquired brain injury.
Contact: Steven Roodenrys