Table 2: Summary of trials involving cognitive interventions in AD patients.

StudyLength and frequencyType of stimulationSampleMMSE
(baseline mean)
Outcome measuresMajor findings

Buschert et al. [59]6 months; 2 hours 1x/wkMulticomponent intervention with focus on CS   
Experimental: 24.5
Control: 25.3
(i) MMSE
(ii) ADAS-Cog
(iii) TMT
(iv) RBANS story memory and recall
(v) QoL-AD
(vi) MADRS
(i) No significant benefit

Chapman et al. [58]8 wks; 90-minute sessions 1x/wkCognitive stimulation   
20.87(i) MMSE
(ii) ADAS-Cog
(iii) TFLS
NPI-irritability and apathy
(iv) QoL-AD
(v) CBIC
(i) Modest positive effects on language, global and functional abilities, and emotional wellbeing in experimental group compared to control group just treated with donepezil

Spector et al. [57]7 wks; 45-minute sessions 2x/wkCognitive stimulation   
Experimental: 14.2
Control: 14.8
(i) MMSE
(ii) ADAS-Cog
(iii) QoL-AD
(iv) HCS
(v) Cornell Scale for Depression in Dementia
(vii) CDR
(i) Significant improvement on the MMSE, ADAS-COG, and QoL-AD

Onder et al. [60]25 wks; 30-minute sessions 3x/wkReality orientation   
Experimental: 20.2
Control: 19.9
(i) MMSE
(ii) ADAS-Cog
(iii) Functional status: Barthel Index,
(iv) IADL
(v) NPI
(vi) Family caregiver outcomes: HRSD, HRSA, Caregiver Burden Inventory, SF-36
(i) Small improvement in MMSE and ADAS-COG

Loewenstein et al. [64]12–16 weeks; 45-minute sessions 2x/wkCognitive rehabilitation/cognitive training   
Experimental: 23.40
Control: 24.53
(i) The face-name association task:
(ii) Orientation
(iii) The continuous performance test
(iv) Procedural object-memory evaluation
(v) Modified Making-Change-For-A-Purchase Task
(vi) Balancing-A-Checkbook Task
(vii) RMBPC
(viii) B-ADLS
(ix) CES-D
(i) Training specific improvement in orientation, face-name recall, processing speed, and making change compared to control group receiving mental stimulation

Davis et al. [65]5 weeks; 1-hour sessions 1x/wk; home practice 30 minutes per day 6x/wkCognitive training   
Experimental: 21.84
Control: 22.78
(i) MMSE
(ii) WMS-R logical memory
(iii) WMS-R visual reproduction
(iv) WAIS-R digit span
(v) VSAT
(vi) Controlled oral word association test
(vii) Category fluency
(viii) Finger taping test
(ix) GDS
(x) Quality of life patient
(i) Improvement in attention, recall of personal information, and face-name recall compared to mock control group
(ii) Results did not extend to other neuropsychological tests or quality of life

Koltai et al. [67]Group program: 5 wks; 1-hour sessions 1x/wk
Individual program: 6 wks; 1-hour sessions 1x/wk with caregiver involvement in last 10–15 minutes
Cognitive rehabilitation/cognitive training   
Experimental: 22.9
Control: 26.6
(i) GDS and relative GDS
(ii) EMQ and relative EMQ
(iii) CERAD
(iv) MMSE
(i) No significant differences between the experimental group and the wait-list control group
(ii) Participants with insight about self-deficits perceived greater gains in memory compared to participants with no insight

Quayhagen et al. [66]8 weeks; 1-hour sessions 5x/wkCognitive training   

(i) Numbers in each group (cognitive training, dyadic counseling, dual supportive seminar, and early-stage day care) not specified
Not reported(i) Immediate memory composite: WMS-R Logical Memory 1 and visual reproduction 1, DRS (memory)
(ii) Delayed memory composite: WMS logical memory 2, visual reproduction 2
(iii) Verbal fluency composite: controlled oral word association, DRS (initiation)
(iv) Problem solving composite: geriatric coping schedule, DRS (conceptualization)
(v) Memory and Behavior Problems Checklist (part A)
(i) Improvement in memory and communication with caregiver
(ii) Other types of interventions (dual support seminar, early-stage daycare) had positive effects on communication and interactions

Cahn-Weiner et al. [71]6 wks; 45-minute sessions 2x/wkMemory training   
Experimental: 24.3
Control: 25.1
(i) HVLT-R
(ii) BVMT-R
(iii) BNT
(iv) COWA
(v) JLO
(vi) TMT (Parts A and B)
(vii) ADL questionnaire
(viii) EMQ
(i) No significant effects

: number of participants in intellectual stimulation program, control group, and group diagnosed with AD. MMSE: Mini-Mental state examination, ADAS-Cog: Alzheimer’s Disease Assessment Scale-Cognitive Subscale, TMT: Trail Making Test, RBANS: Repeatable Battery for the Assessment of Neuropsychological Status Versions A (before testing) and B (after testing), QoL-AD: quality of life-Alzheimer’s disease, MADRS: Montgomery-Asberg Depression Rating Scale, TFLS: Texas Functional Living Scale, NPI: Neuropsychiatric Inventory, CIBIC: Clinician’s Interview-Based Impression of Change, HCS: Holden Communication Scale, CAPE-BRS: The Clifton Assessment Procedures for the Elderly-Behaviour Rating Scale, CDR: The Clinical Dementia Rating Scale, IADL: instrumental activities of daily living, HRSD: Hamilton Rating Scales for Depression, HRSA: Hamilton Rating Scales for Anxiety, SF-36: The Medical Outcomes Study 36-Item Short-Form General Health Survey, RMBPC: The Revised Memory and Behavior Problems Checklist, B-ADLS: The Bayer Activities of Daily Living Scale, CES-D: The Center for Epidemiological Studies-Depression Scale, IQCODE: the informant questionnaire of the cognitive decline in the elderly scale, WMS-R: Wechsler Memory Scale-Revised, WAIS-R: Wechsler Adult Intelligence Scale-Revised, VSAT: The Verbal Series Attention Test, GDS: Geriatric Depression Scale, EMQ: Everyday Memory Questionnaire, CERAD: Consortium to Establish a Registry for Alzheimer’s Disease Test Battery, DRS: The Mattis Dementia Rating Scale, HVLT-R: Hopkins Verbal Learning Test Revised, BVMT-R: Brief Visual Spatial Memory Test Revised, BNT: Boston Naming Test, COWA: Controlled Oral Word Association Test, and JLO: Judgment of Line Orientation.