Priming performance in Alzheimer's disease: The role of task sensitivity
AbstractStudies examining implicit memory performance in Alzheimer's disease (AD) have yielded inconsistent findings, with these patients demonstrating impaired performance within some priming studies and intact performance within others. The present study examined the role of task sensitivity in detecting impaired priming in memory-impaired patients. Twelve healthy older adults and 12 AD patients were administered a picture fragment identification test. Task sensitivity was increased by employing stimulus cues expected to produce larger and more variable priming effects than obtained in previous studies. A simple comparison of priming scores revealed that the AD patients demonstrated significantly impaired priming relative to normal control participants. However, further analysis of priming in relation to certain stimulus characteristics revealed that AD patients often demonstrated impaired priming when overall priming effects were large but relatively intact priming when priming effects were small. These findings suggest that the prevention of ceiling effects in control participants may aid in the detection of impaired priming in patient populations. (JINS, 2001, 7, 294–301.) (Received May 24 1999)(Revised March 6 2000) (Accepted March 14 2000) Key Words: Alzheimer's disease; Priming; Implicit memory; Picture fragment identification. Correspondence: c1 Reprint requests to: Lauren E. Norton, Ph.D., Massachusetts General Hospital, Psychology Assessment Center, 5 Emerson Place, Suite 105, Boston, MA 02114-2696. E-mail: lnorton@partners.org |