 |
Board of Honors Tutors
Andrew E. Budson, M.D.
Assistant Professor of Neurology / Harvard Medical School
Division of Cognitive and Behavioral Neurology
Brigham and Women's Hospital
http://neuro-www.mgh.harvard.edu:16080/~budson/
abudson@partners.org
The major interest of this laboratory is to gain an understanding of memory distortions in patients with Alzheimer's disease (AD). Many AD patients suffer from distortions in memory that may cause them to believe, for instance, that they turned off the stove or took their medications when they have only thought about performing these activities. Such false memories can impair the ability of these patients to live independently. We use both psychology experiments to explore memory distortions in patients and event-related potential EEG studies to examine brain correlates of these false memories in patients and controls. Specifically, we have looked at two different types of memory which are believed to involve different neuroanatomical systems: item-specific recollection (the specific details of a prior encounter) and gist memory (the general meaning or idea conveyed by a collection of related items). While both item-specific recollection and gist information support true recognition, false recognition commonly occurs when participants remember gist but not item-specific information. We have found that patients with AD show deficits in both item-specific recollection and gist memory. However, when information is repeated across multiple trials AD patients increase their gist-but not their item-specific recollection-leading to an increase in false memories.
We have used different techniques to better understand the neurophysiological basis for the increase in false memories observed in AD patients. For example, using patients with brain damage, we have found that patients with lesions in dorsolateral prefrontal cortex (Brodmann areas 9 & 46) are unable to build up item-specific recollection and suppress their false recognition as control subjects can. In a different study, using event-related potential EEGs in healthy young adults, we have found that whereas left parietal activity indexes gist memory (distinguishing true recognition versus correct rejection of novel items), additional late frontal activity is needed for item-specific recollection (distinguishing true versus false memories).
Students have the opportunity to be involved in a variety of studies exploring memory distortions. Students will work directly with the principal investigator, Dr. Andrew Budson, and will be given the opportunity to participate in all stages of a project. Students will have the opportunity to interact with patients, learn how to design, perform and interpret psychology and event-related EEG experiments, and gain additional clinical experience in behavioral neurology if desired.
|
|
