Ignite Creation Date:
2024-05-05 @ 9:36 AM
Last Modification Date:
2024-10-26 @ 9:04 AM
Study NCT ID:
NCT00004557
Status:
COMPLETED
Last Update Posted:
2008-03-04
First Post:
2000-02-08
Brief Title:
Models of Disordered Knowledge and Memory Systems in Dementia and Related Disorders
Sponsor:
National Institute of Mental Health NIMH
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
Models of Disordered Knowledge and Memory Systems in Dementia and Related Disorders
Status:
COMPLETED
Status Verified Date:
1999-02
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Patients with Alzheimers disease AD perform poorly on tasks dependent on access to and utilization of previously acquired knowledge and skills It has been commonly assumed that impaired knowledge in AD as well as in other patients with cortical lesions is due to an actual loss or disorganization of a specific knowledge base or system This hypothesis has however recently been called into question by data from tasks that purport to tap knowledge on a more automatic and implicit level For example although AD patients are impaired on object naming and verbal fluency tasks they show a normal pattern of semantic facilitation on reaction time based priming tasks In fact the level of facilitation or activation on these tasks has often been reported to be greater in AD patients than in normal individuals These and similar data have been used to support arguments that performance decrements in AD patients are due to deficits in attentional andor retrieval processes rather than a degradation of knowledge stores The central focus of this project will be to test a model of the semantic representations of object that predicts increased facilitation or hyperpriming in AD patients as a result of degraded representations The relationship between performance on on-line priming tasks visual attention and spatial processes and explicit and implicit measures of memory also will be examined In addition to normal controls patients with cognitive and memory impairments but without semantically-based naming difficulties elderly depressed Huntingtons disease Korsakoffs disease will serve as controls for overall slowness of response and degree of explicit memory deficit
Detailed Description:
Patients with Alzheimers disease AD perform poorly on tasks dependent on access to and utilization of previously acquired knowledge and skills It has been commonly assumed that impaired knowledge in AD as well as in other patients with cortical lesions is due to an actual loss or disorganization of a specific knowledge base or system This hypothesis has however recently been called into question by data from tasks that purport to tap knowledge on a more automatic and implicit level For example although AD patients are impaired on object naming and verbal fluency tasks they show a normal pattern of semantic facilitation on reaction time based priming tasks In fact the level of facilitation or activation on these tasks has often been reported to be greater in AD patients than in normal individuals These and similar data have been used to support arguments that performance decrements in AD patients are due to deficits in attentional andor retrieval processes rather than a degradation of knowledge stores The central focus of this project will be to test a model of the semantic representations of object that predicts increased facilitation or hyperpriming in AD patients as a result of degraded representations The relationship between performance on on-line priming tasks visual attention and spatial processes and explicit and implicit measures of memory also will be examined In addition to normal controls patients with cognitive and memory impairments but without semantically-based naming difficulties elderly depressed Huntingtons disease Korsakoffs disease will serve as controls for overall slowness of response and degree of explicit memory deficit
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 92-M-0075 | None | None | None |