Long-term effects of cognitive training on everyday functional outcomes in older adults.
BACKGROUND
Cognitive training has been shown to improve cognitive abilities in older adults but the effects of cognitive training on everyday function have not been demonstrated.


OBJECTIVE
To determine the effects of cognitive training on daily function and durability of training on cognitive abilities.


METHODS
Five-year follow-up of a randomized controlled single-blind trial with 4 treatment groups. A volunteer sample of 2832 persons (mean age, 73.6 years; 26% black), living independently in 6 US cities, was recruited from senior housing, community centers, and hospitals and clinics. The study was conducted between April 1998 and December 2004. Five-year follow-up was completed in 67% of the sample.


METHODS
Ten-session training for memory (verbal episodic memory), reasoning (inductive reasoning), or speed of processing (visual search and identification); 4-session booster training at 11 and 35 months after training in a random sample of those who completed training.


METHODS
Self-reported and performance-based measures of daily function and cognitive abilities.


RESULTS
The reasoning group reported significantly less difficulty in the instrumental activities of daily living (IADL) than the control group (effect size, 0.29; 99% confidence interval [CI], 0.03-0.55). Neither speed of processing training (effect size, 0.26; 99% CI, -0.002 to 0.51) nor memory training (effect size, 0.20; 99% CI, -0.06 to 0.46) had a significant effect on IADL. The booster training for the speed of processing group, but not for the other 2 groups, showed a significant effect on the performance-based functional measure of everyday speed of processing (effect size, 0.30; 99% CI, 0.08-0.52). No booster effects were seen for any of the groups for everyday problem-solving or self-reported difficulty in IADL. Each intervention maintained effects on its specific targeted cognitive ability through 5 years (memory: effect size, 0.23 [99% CI, 0.11-0.35]; reasoning: effect size, 0.26 [99% CI, 0.17-0.35]; speed of processing: effect size, 0.76 [99% CI, 0.62-0.90]). Booster training produced additional improvement with the reasoning intervention for reasoning performance (effect size, 0.28; 99% CI, 0.12-0.43) and the speed of processing intervention for speed of processing performance (effect size, 0.85; 99% CI, 0.61-1.09).


CONCLUSIONS
Reasoning training resulted in less functional decline in self-reported IADL. Compared with the control group, cognitive training resulted in improved cognitive abilities specific to the abilities trained that continued 5 years after the initiation of the intervention.


BACKGROUND
clinicaltrials.gov Identifier: NCT00298558.
Willis
Sherry L
SL
Department of Human Development and Family Studies, Pennsylvania State University, State College, PA 16801. slw@psu.edu
Tennstedt
Sharon L
SL
Marsiske
Michael
M
Ball
Karlene
K
Elias
Jeffrey
J
Koepke
Kathy Mann
KM
Morris
John N
JN
Rebok
George W
GW
Unverzagt
Frederick W
FW
Stoddard
Anne M
AM
Wright
Elizabeth
E
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D003071:Cognition; D003072:Cognition Disorders / Q000517:prevention & control*; D015928:Cognitive Behavioral Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008568:Memory; D008606:Mental Processes; D016037:Single-Blind Method