Semantic Priming in Alzheimer's Dementia: Evidence for Dissociation of Automatic and Attentional Processes

The nature of the semantic memory deficit in dementia of the Alzheimer's type (DAT) was investigated in a semantic priming task which was designed to assess both automatic and attention-induced priming effects. Ten DAT patients and 10 age-matched control subjects completed a word naming semantic priming task in which both relatedness proportion (RP) and stimulus-onset asynchrony (SOA) were varied. A clear dissociation between automatic and attentional priming effects in both groups was demonstrated; however, the DAT subjects' pattern of priming deviated significantly from that of the normal controls. The DAT patients failed to produce any priming under conditions which encouraged automatic semantic processing and produced facilitation only when the RP was high. In addition, the DAT group produced hyperpriming, with significantly larger facilitation effects than the control group. These results suggest an impairment of automatic spreading activation in DAT and have implications for theories of semantic memory impairment in DAT as well as models of normal priming.

[1]  Janellen Huttenlocher,et al.  The source of relatedness effects on naming latency. , 1983 .

[2]  L. Postman,et al.  Norms of word association , 1970 .

[3]  Mark S. Seidenberg,et al.  Pre- and postlexical loci of contextual effects on word recognition , 1984, Memory & cognition.

[4]  D. S. Pate,et al.  Lexical Priming by Pictures and Words in Normal Aging and in Dementia of the Alzheimer's Type , 1996, Brain and Language.

[5]  K. Heyer,et al.  On the nature of the proportion effect in semantic priming , 1985 .

[6]  T. Bashore,et al.  Age differences in word and language processing , 1995 .

[7]  D. Bub,et al.  Increased semantic priming in patients with dementia of the Alzheimer's type. , 1994, Journal of clinical and experimental neuropsychology.

[8]  R. Schvaneveldt,et al.  Facilitation in recognizing pairs of words: evidence of a dependence between retrieval operations. , 1971, Journal of experimental psychology.

[9]  David Navon,et al.  Allocation of Attention According to Informativeness in Visual Recognition , 1983, The Quarterly journal of experimental psychology. A, Human experimental psychology.

[10]  G. Humphreys,et al.  Basic processes in reading : visual word recognition , 1993 .

[11]  Mark S. Seidenberg,et al.  Priming and semantic memory loss in Alzheimer's disease , 1989, Brain and Language.

[12]  Alan S. Brown,et al.  Information Processing and Cognition: The Loyola Symposium , 1976 .

[13]  Max Coltheart,et al.  The MRC Psycholinguistic Database , 1981 .

[14]  David A. Balota,et al.  Semantic priming effects, lexical repetition effects, and contextual disambiguation effects in healthy aged individuals and individuals with senile dementia of the Alzheimer type , 1991, Brain and Language.

[15]  Avishai Henik,et al.  Capacity demands of automatic processes in semantic priming , 1994, Memory & cognition.

[16]  H. Chenery.  Semantic priming in Alzheimer's dementia , 1996 .

[17]  A. D. Groot,et al.  Primed Lexical Decision: Combined Effects of the Proportion of Related Prime-Target Pairs and the Stimulus-Onset Asynchrony of Prime and Target , 1984 .

[18]  W. Jagust,et al.  Automatic semantic priming with various category relations in Alzheimer's disease and normal aging , 1991 .

[19]  R. Knight.  Facilitation by semantic priming in Alzheimer's disease and control groups matched for accuracy of word recognition. , 1996 .

[20]  R. Nebes,et al.  Sparing of semantic memory in Alzheimer's disease. , 1984, Journal of abnormal psychology.

[21]  M. Folstein,et al.  Clinical diagnosis of Alzheimer's disease , 1984, Neurology.

[22]  J. H. Neely,et al.  Semantic priming in the pronunciation task: The role of prospective prime-generated expectancies , 1990, Memory & cognition.

[23]  Arnold J.W.M. Thomassen,et al.  Primed-lexical decision: the effect of varying the stimulus-onset asynchrony of prime and target , 1986 .

[24]  R. Nebes.  Semantic memory in Alzheimer's disease. , 1989, Psychological bulletin.

[25]  Automatic semantic facilitation in Alzheimer's disease. , 1996, Journal of clinical and experimental neuropsychology.

[26]  C. Bushell,et al.  Dissociated Identity and Semantic Priming in Broca's Aphasia: How Controlled Processing Produces Inhibitory Semantic Priming , 1996, Brain and Language.

[27]  M. Posner,et al.  Attention and cognitive control. , 1975 .

[28]  Methodological control of semantic priming in Alzheimer's disease. , 1996 .

[29]  Allan Collins,et al.  A spreading-activation theory of semantic processing , 1975 .

[30]  J. H. Neely.  Semantic priming and retrieval from lexical memory: Roles of inhibitionless spreading activation and limited-capacity attention. , 1977 .

[31]  James R. Tweedy,et al.  Facilitating Word Recognition: Evidence for Strategic and Automatic Factors , 1981 .

[32]  J. H. Neely.  Semantic priming effects in visual word recognition: A selective review of current findings and theories. , 1991 .

[33]  Marilyn Hartman,et al.  The use of semantic knowledge in Alzheimer's disease: Evidence for impairments of attention , 1991, Neuropsychologia.

[34]  M. Yamada,et al.  [Dementia rating scale]. , 1997, Nihon rinsho. Japanese journal of clinical medicine.

[35]  K. Heyer.  Manipulating attention-induced priming in a lexical decision task by means of repeated prime-target presentations , 1986 .

[36]  R W Schvaneveldt,et al.  Semantic-context effects on word recognition: Influence of varying the proportion of items presented in an appropriate context , 1977, Memory & cognition.