Attentional Control Training in Older Adults: Efficacy, Transfer and Brain Substrates
Condition: Inhibition (Psychology); Updating; General Knowledge; No Training
Study type: Interventional

Summary: 
      Formal education and cognitively stimulating hobbies and profession have a protective effect
      against age-related cognitive decline and Alzheimer's disease. It is therefore possible that
      providing cognitively stimulating interventions at a later age increases neuroplasticity and
      brain resilience. Processes of updating and inhibition are both impaired by aging. Several
      studies have shown that updating can be improved but very few studies targeted inhibition in
      spite of the fact that it is impaired in older adults. The aim of this study is to assess the
      effect of cognitive interventions that will target either of these two components. The
      investigators will examine the effect on behavior, brain measures and transfer tasks. The
      investigators will also assess whether the efficacy varies as a function of personal
      variables such as prior cognitive profile, reserve proxies, genetic polymorphisms and brain
      markers.
    

Detailed description: 
      Formal education and cognitively stimulating hobbies and profession have a protective effect
      against age-related cognitive decline and Alzheimer's disease. The cognitive reserve model
      suggests that engaging in cognitively stimulating activities may induce brain processes
      and/or morphological characteristics that make individuals more resilient to the effects of
      brain damage. It is therefore possible that providing cognitive interventions at a later age
      amplify similar neuroplastic processes and thus reduce the deleterious effects of aging.
      Cognitive interventions refer to programs and/or strategies aimed at increasing or optimizing
      cognitive performance. Many of these programs target working memory (WM), which is defined as
      the ability to control attention in order to keep information active and accessible. Miyake's
      influential model proposes that WM relies on the coordinated functioning of a small set of
      attentional control components. Here the investigators will focus on two of these components:
      inhibition and updating. Training those two components might reveal critical as they are
      impaired in aging and subtend a range of more complex cognitive processes. Furthermore, they
      rely on distinct brain networks and are sensitive to cognitive lifestyle. Several studies
      have shown that updating capacities of older adults can be improved by cognitive training but
      very few studies targeted inhibition in spite of the fact that it is severly impaired by
      aging. The aim of this study is to assess the effect of cognitive interventions that will
      target either of these two components and compare their effect to that of an active control
      training. The investigators will examine their effect on behavior, brain measures and
      transfer tasks. The investigators will also assess whether the efficacy varies as a function
      of personal variables such as prior cognitive profile, reserve proxies, genetic polymorphisms
      and brain markers. The investigators will also examine the cumulative effect of training by
      measuring efficacy at three time points for the proximal outcomes and at five time points for
      the distal outcomes. Finally, a group of younger adults will be tested at baseline to assess
      whether training normalize performance, that is, whether the performance of older adults
      after training is improved to the level of typical young adults.

      90 healthy older adults (60-85 years) will be recruited for this study, as well as thirty
      young adults (20-35 years) who will complete only the initial assessment (PRE). All
      participants will be recruited from the community and living in the Montreal area. A
      telephone interview will provide initial selection information. Eligible persons will be
      invited to come to the laboratory for a standardized clinical and neuropsychological battery
      in order to evaluate their clinical status and cognitive functioning. The older adults will
      be randomly assigned to one of three intervention conditions (Inhibition, Updating, Active
      control). Updating will be trained using N-back-like exercises whereas inhibition will be
      trained with Stroop-like exercises. Different types of stimuli will be used to facilitate
      transfer. The control intervention will include exercises on general knowledge and
      vocabulary. All training will be computerized. Training will be provided in 12 half-hours
      training sessions. Outcome measures will be taken no more than two weeks prior to training
      (PRE), between Session 6 and 7 (POST1) and no more than one week following Session 12
      (POST2). Participants will be trained in small groups of 6 to 10 individuals recruited in
      about 6 waves. The first two waves will allow to pilot the procedure/team and will be accrued
      to the whole trial if the training procedure and outcome measures remain unchanged.
    

Intervention name(s): Updating; Inhibition; General knowledge
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Updating is trained across 12 sessions using N-back-type exercises. Training is performed on a samsung galaxy tab2. Each session lasts 30 minutes. The difficult is reset and the nature of the stimuli (numbers vs. symbols) is changed halfway in each session.; Inhibition is trained across 12 sessions with Stroop-like exercises. Training is performed on a samsung galaxy tab2. Each session lasts 30 minutes. The difficult is reset and the nature of stimuli (letters vs. numbers) is changed halfway in each session.; General Knowledge is trained across 12 sessions. Participants complete four-choice questions relating to general knowledge and vocabulary and are provided with the correct answer and a short explanation. Questions are displayed one by one on a computer screen with a maximum of 20 seconds per question. Each session lasts 30 minutes and includes 2 blocks of 40 new questions each (about 220 seconds per block). Questions with wrong answers are displayed again at the end of each block.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Older participants are randomly assigned to one of three intervention conditions (Inhibition ; Updating ; General knowledge).
Young participants only complete the initial assessment.
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Supportive Care
Keywords: Cognitive intervention; Cognitive training; Aging; Working memory; Cognitive reserve; Brain imaging; Brain plasticity; Polymorphisms; Transfer; Inhibition; Updating