The Declarative/Procedural Model: The neurochemistry of language
- Tony Jennings, University of Sussex
- Glendinning Lecture Theatre 2D67, UWE Bristol
The physiology and neurochemistry of language are not obvious areas of exploration, but a recent proposal has huge implications on the fields of Linguistics and Neurology. The declarative/procedural model proposed by Michael Ullman (2001a; 2001b; 2004) claims the declarative memory system underlies the mental lexicon, whilst the procedural memory system underlies the mental grammar. The model makes very specific predictions about language and its mechanisms in the brain.
One particular prediction is of interest to linguists and neurologists alike. A recent study (Ullman et al 2002) has implicated specific neurochemicals with language use. Estrogen and acetylcholine demonstrably improve processing in temporal lobe regions; under the Declarative/Procedural Model, declarative/lexical language processing should improve accordingly in proportion to levels of these two neurochemicals.
The effect of estrogen on language use is tested by means of a short experiment. Estrogen levels are indirectly measured and compared with participants’ use of regular, irregular and novel past-tense inflection forms. Following Ullman (2001a), regular forms are constructed anew in procedural memory, irregular forms are retrieved from the declarative memory system, and novel forms should elicit a participants’ personal preference for either declarative or procedural language processing. It is predicted that, as estrogen levels increase within an individual participant, so too will their reliance on the declarative memory system. This should become apparent in language use, with increased use of irregular verb inflections and lower use of regular inflections. In sum, results are expected to show, in line with Ullman et al (2002) that estrogen levels positively correlate with use of irregular verb inflections.
If attested, the DP model has important implications in understanding the neural mechanisms of language, and the evidence presented here provides a potential neurobiological basis for language-processing differences between sexes. Moreover, since declarative and procedural memory systems are not domain-specific to language, the means by which language operates should be applicable to non-language domains using similar neural mechanisms. In brief, the model demonstrates that the future of linguistics has a hugely important role in neuroscience, including the mechanisms underlying nonlanguage disorders such as Alzheimer’s, Parkinson’s, Dementia and Amnesia, among others.
Journal of Psycholinguistic Research, vol. 30(1), p37–69. Ullman, M.T. (2001b)
A neurocognitive perspective on language: the declarative/procedural model. Nature Reviews Neuroscience, vol. 2, p717–726.Ullman, M.T. (2004)
Contributions of memory circuits to language: the declarative/procedural model. Cognition, vol. 92, p231–270. Ullman, M.T, Estabrooke, I.V., Steinhauer, K., Brovetto, C., Pancheva, R., Ozawa, K., Mordecai, K., Maki, P. (2002)
Sex differences in the neurocognition of language, Brain and Language, vol. 83, p9–224.
One particular prediction is of interest to linguists and neurologists alike. A recent study (Ullman et al 2002) has implicated specific neurochemicals with language use. Estrogen and acetylcholine demonstrably improve processing in temporal lobe regions; under the Declarative/Procedural Model, declarative/lexical language processing should improve accordingly in proportion to levels of these two neurochemicals.
The effect of estrogen on language use is tested by means of a short experiment. Estrogen levels are indirectly measured and compared with participants’ use of regular, irregular and novel past-tense inflection forms. Following Ullman (2001a), regular forms are constructed anew in procedural memory, irregular forms are retrieved from the declarative memory system, and novel forms should elicit a participants’ personal preference for either declarative or procedural language processing. It is predicted that, as estrogen levels increase within an individual participant, so too will their reliance on the declarative memory system. This should become apparent in language use, with increased use of irregular verb inflections and lower use of regular inflections. In sum, results are expected to show, in line with Ullman et al (2002) that estrogen levels positively correlate with use of irregular verb inflections.
If attested, the DP model has important implications in understanding the neural mechanisms of language, and the evidence presented here provides a potential neurobiological basis for language-processing differences between sexes. Moreover, since declarative and procedural memory systems are not domain-specific to language, the means by which language operates should be applicable to non-language domains using similar neural mechanisms. In brief, the model demonstrates that the future of linguistics has a hugely important role in neuroscience, including the mechanisms underlying nonlanguage disorders such as Alzheimer’s, Parkinson’s, Dementia and Amnesia, among others.
Journal of Psycholinguistic Research, vol. 30(1), p37–69. Ullman, M.T. (2001b)
A neurocognitive perspective on language: the declarative/procedural model. Nature Reviews Neuroscience, vol. 2, p717–726.Ullman, M.T. (2004)
Contributions of memory circuits to language: the declarative/procedural model. Cognition, vol. 92, p231–270. Ullman, M.T, Estabrooke, I.V., Steinhauer, K., Brovetto, C., Pancheva, R., Ozawa, K., Mordecai, K., Maki, P. (2002)
Sex differences in the neurocognition of language, Brain and Language, vol. 83, p9–224.