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NeuroRehabilitation 35 (2014) 261–270 DOI:10.3233/NRE-141121 IOS Press

A single case study of computerised cognitive training for older persons with mild cognitive impairment Maurice Finn∗ and Skye McDonald School of Psychology, University of New South Wales, Sydney, NSW, Australia

Abstract. The results of a multiple baseline single case study using computerised cognitive training in older adults with Amnestic Mild Cognitive Impairment (aMCI) are reported. Two participants each completed 40 sessions of training in two phases: an initial phase that trained attention, processing speed and cognitive flexibility, followed by a mixed memory and execution functions phase. It was hypothesised that participants would improve with practice on the trained tasks, that the benefits of training would generalise to non-trained neuropsychological probe measures, and that training would result in improved perceptions of memory and mood. Results indicated that one participant showed improved performance on untrained measures of attention and reasoning. On pre/post measures both participants reported less frequent cognitive failures in everyday life and improved mood following training. The results are discussed along with suggestions for future research. Keywords: Aged, cognitive training, mild cognitive impairment, single case study

1. Introduction Older people with Mild Cognitive Impairment (MCI) have cognitive impairment significantly greater than would be expected due to age (Petersen et al., 1999; Petersen, 2003), with deficits in memory, visuospatial and executive functions (Belleville, 2008; Bennett et al., 2002). Two subtypes of MCI (Amnestic – Single domain and Amnestic – Multiple domain) have been associated with the onset of Alzheimer’s disease (Rasquin et al., 2005), and interventions have aimed at compensating for memory loss by teaching participants memory strategies (Rapp, Brenes & Marsh, 2002; Belleville et al., 2006). However these kind of interventions do not directly target cognition, instead aiming to better equip participants to cope with cognitive loss. ∗ Address

for correspondence: Maurice Finn, Clinical Psychologist, Aged Care – Memory Clinic, Royal North Shore Hospital, 2C Herbert St, St. Leonards, NSW 2065, Australia. Tel.: +61 2 9462 9333; Fax: +61 2 9906 4301; E-mail: [email protected].

An alternative approach is the use of computerised cognitive training, with repeated practice on exercises that are aimed at improving or maintaining a range of cognitive skills such as attention, working memory, processing speed, cognitive flexibility, learning and memory. This form of training draws inspiration from advances in neuroscience that demonstrate plasticity in the brain throughout the lifespan and seeks to harness these processes to improve cognition (Dinse, 2006). There are also practical advantages as computerised exercises can be adapted to the level of ability of the individual, are able to train a range of cognitive functions, can provide consistent and timely feedback on progress and use novel exercises (Mahncke et al., 2006). In elderly populations with MCI, there have been initial efforts to explore the efficacy of computerised cognitive training via group comparison studies (Rozzini, Costardi, Vicini, Chilovi, & Franzoni, 2007; Talassi, Guerreschi, Feriani, & Fedi, 2007; Cipriani, Bianchetti, & Trabucchi, 2006; Barnes et al., 2009). A recent review (Fauconau, Wu, Boulay, De Rotrou

1053-8135/14/$27.50 © 2014 – IOS Press and the authors. All rights reserved

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& Rigaud, 2009) described the area as promising but lacking in randomised controlled trials. A subsequent pilot RCT by the authors (Finn & McDonald, 2011) found evidence of improved visual attention following cognitive training but noted problems with adherence to the training regime. However the conclusions that can be drawn from the existing literature are limited by methodological problems such as a lack of adequate control groups, small sample size, heterogenous participants, and inconsistent findings. Instead of using an RCT design, small scale exploratory research can instead turn to the single case experimental design (SCED), of which there is a long tradition in neuropsychological rehabilitation. A singlecase design allows the researcher to identify the efficacy of the intervention for a specific individual. Tate et al. (2008) note situations where single case designs can be advantageous. Their criteria would suggest that single case designs have a role to play in research in cognitive training for aMCI as this is an area with very few published RCT’s which may well reflect the problem that people with aMCI are heterogeneous making it difficult to find sufficient numbers for RCT’s and generating problems with heterogeneity swamping any treatment effects as noted above. However, much of the existing single case research literature suffers from methodological flaws that limit the conclusions that can be drawn For example, many studies lack adequate baseline data, fail to report raw data points, omit replication across subjects, therapists or settings, do not measure generalisation or simply report pre/post measures (Backman & Harris, 1999). Clearly there is a need for well-designed single case research to advance the treatment literature. In the published literature, single case designs are frequently reported but rarely in a treatment context, with many studies simply reporting on either features or progression of the condition (for example, Jacobson et al., 2009). Most of the published treatment studies look at different populations such as Alzheimer’s disease, stroke, traumatic brain injury, and Parkinsons’s disease rather than MCI. The very few MCI treatment studies that do exist tend to focus on improving or altering behaviour and/or function, relying on outcome measures that reflect increased functional, rather than cognitive capacity. However, the diagnostic criteria for MCI stipulate preserved basic activities of daily living / minimal impairment in complex instrumental functions, making measurement of impaired function in this group problematic. An example of remediating function is Clare et al. (2009) who reported improved associa-

tive learning following cognitive rehabilitation in a 77 year old-woman with MCI. The primary outcome was attainment of therapy goals at each session, with cognition measured via an associative learning task given pre/post rather than at each session. The study reported here was designed to meet the criteria for adequate methodological quality according to the SCED-Scale developed by Tate et al. (2008). It used a multiple baseline single case design, with clearly specified target measures, and providing for replication across participants. This study avoided relying solely on functional or behavioural measures, instead identifying cognitive probes that could be used repeatedly while minimising practice effects. The study design described here also attempted to address some of the limitations identified in the RCT completed by the authors (Finn & McDonald, 2011). Anecdotally, and from direct observation, some participants in that study lacked focus and attention while training and favoured exercises they were better at, over potentially more beneficial ones. The training program itself trained participants in all cognitive domains simultaneously, which may have resulted in them making more effort on tasks that did not tax an impaired memory. In addition, it was reported by participants that they found the memory exercises quite daunting, and this was reflected in a flatter learning curve across the training program. Another limitation was that participants completed pre-post measures at the clinic but training was done at home using their own computers, with variations in the quality of graphical display and screen response times. The home environment was also replete with distractions and potential interruptions. There were also variations in the length of time it took participants to complete the program. Several steps were taken to overcome these limitations. Rather than training at home, participants attended the clinic and were given assistance and prompts to complete tasks as required. The dose of training was also increased from 30 to 40 sessions. Training intensity and duration was managed by a schedule of twice-weekly sessions of 90 minutes in duration to enable the program to be competed in full over twelve clinic visits over a six week period (with an additional two weeks for collection of baseline data). Memory training exercises were not introduced until the halfway point of the training program to allow for both familiarisation with the program and training of functions such as attention and processing speed that may support learning. This design also meant that oneon-one coaching could be provided at each session to

M. Finn and S. McDonald / Single case design cognitive training mild cognitive impairment

promote treatment adherence. By measuring a range of cognitive functions at each clinic visit it was possible to observe if training resulted in gains on similar untrained tasks.

2. Aims This study set out to explore the benefits of a more intensive approach designed to promote treatment adherence. Training began with attention and executive functions being trained first, followed by memory exercises introduced in a second phase of training. The primary aim was to measure the impact of training on measures of cognition. Participants were also asked to complete pre and post measures of mood and cognitive failures. It was hypothesised that training would lead to improved performance as a function of phase of training, with attention and executive functions improving in the first phase of training followed by memory in the second phase. This would also lead to improved mood and a reduction in self-reported cognitive lapses in everyday life. 2.1. Design The study was designed as a multiple baseline singlecase design with replication across participants. The participants were staggered, commencing one week apart. Baseline data was collected on four to six sessions prior to commencement of training. Pre/post data were collected and transfer of training was measured by the use of treatment probes administered following training at each clinic visit. The probes are described in more detail below.

3. Method The diagnosis of MCI was originally determined by the consensus opinion of a Staff Specialist Geriatrician, Psychogeriatrician and Clinical Psychologist following a comprehensive assessment as detailed in Finn & McDonald (2011). Both participants were reevaluated on entry to the study against standardised criteria for MCI (Winblad et al., 2004). Participants who were on stable doses of cholinesterase inhibitors for the duration of the study were eligible to take part, but participants who commenced taking these medications during the study were excluded. Only participants with a diagnosis of either MCI – Amnestic (single

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domain) or MCI – Amnestic (multiple domain) were considered for this study. In addition, participants were required to have intact global cognitive functioning (score >24) on the Mini Mental State Examination (MMSE) (Folstein, Folstein & McHugh, 1975); and absence of untreated psychiatric illness or substance abuse problems; and absence of visual, auditory or motor impairment that would hinder use of a computer. Sample: Three community-dwelling, older (age >60 years) clients of the Aged Care Services Memory Clinic at Royal North Shore Hospital, with a current diagnosis of MCI were selected to participate. One participant dropped out after the initial baseline session due to personal reasons. Both the remaining participants had completed a full neuropsychological assessment and were considered to be at risk of progressing to dementia. The study was approved by the Northern Sydney Local Health District Human Research Ethics Committee (Protocol Number NEAF 0712-247M). Before entering the study, participants were fully informed about the research project and the risks of participating in it. They gave written informed consent on a form that was approved by the Ethics Committee. All data were kept strictly confidential by use of coding for participant response sheets and materials. 3.1. Probe measures The treatment probes were selected from two sources, (Cambridge Brain Sciences http://www.cam bridgebrainsciences.com and Lumosity http://www. lumosity.com) and were tasks that were deemed suitable for use as treatment probes as, on any given trial, the parameters of each task remained set, while the details changed, minimising practice effects. For example, on a Paired Associates task the location of both the pairs on the screen and the type of objects to be paired changed on each trial, so locations could not be memorised. On a version of the Trail Making task, the number of connections to be made was held constant, but the exact placement of the numbers and/or letters on the screen varied. The probes were not simply training exercises by another name as they differed from the trained tasks in several important ways. The probes always began at the same level on each occasion whereas the trained tasks commenced at the highest level reached in the previous session. Importantly, the probes did not become more difficult as the program progressed and nor did they provide feedback or encouragement on performance.

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Also the ratio of probes to any given training exercise was approximately 1 : 4 meaning that the probes were attempted much less often than any of the training exercises. The treatment probes measuring cognitive functions given to participants at each visit were as follows: Simple and divided attention (Trail Making Test – Part A; Trail Making Test – Part B); Immediate visual memory (Paired Associates test); Visual abstract reasoning (Odd One Out). A visual recognition task (Pattern Recognition) was also piloted but considered unsuitable due to problems with both a ceiling effect and repeated sequences. Trail Making Test Part A & B: For both these probes the participant is required to move the cursor using the mouse to either sequence numbers (Part A) in order (1, 2, 3, 4, etc.) or alternate between sequencing numbers and letters (1-A, 2-B, 3-C, etc.) as quickly as possible while avoiding errors. When a correct connection is made, the pathway is illuminated on screen by a blue line, while errors are shown with an “x”. The data collected is the time to completion in seconds. Paired Associates test. Participants are shown a series of boxes and the objects located inside are briefly exposed. In the test phase, the objects are displayed in the centre of the screen and the participant is asked to click on the box in which the object was located. Correct responses result in an extra box being added on the next trial. After three errors the task is discontinued. The data collected is the highest span correct (i.e. four paired associates correctly recalled would result in a score of 4 even if errors had been made on earlier trials. Odd One Out: The participant must work out which of nine patterns is the odd one out, solving as many problems as possible within a three minute period. Problems become increasingly difficult as the task progresses. The participants must solve a novel set of problems each time they undertake the task. Data collected is the total number of puzzles completed correctly less any errors. 3.2. Pre/post measures Mood was measured using the Depression Anxiety and Stress Scale (Lovibond & Lovibond, 1995) 21 item version. Everyday cognitive functioning was measured by the Cognitive Failures Questionnaire (Broadbent, Fitzgerald, Cooper & Parkes, 1982) which is a reliable and validated 25 item self-report measure of the frequency of various cognitive failures. In this study

participants were asked to report on cognitive failures in the past month. 3.3. Computerised cognitive training package The training software was supplied by Lumosity Inc. (http://www.lumosity.com). There were forty training sessions each containing five cognitive exercises. On instructions from the researchers, Lumosity provided a training program that divided training into two phases each of twenty sessions. The initial phase included exercises that nominally target attention, cognitive flexibility and problem solving. Exercises that train memory were introduced in the second phase and formed approx. 50% of the training. There were four broad cognitive domains targeted by training: nominally attention, processing speed, visual memory and cognitive control. All participants began at the same level of difficulty. On each exercise, once a predetermined criterion of performance was reached, the level of difficulty was increased. Participants completed pre/post measures and the training at the clinic and were asked not to access the Lumosity website nor any other similar sites while the training was in progress. The training exercises used here are described in detail in Appendix One. The software provided feedback to participants as they completed each exercise and a summary of progress after each session. The participants completed the training in the clinic with guidance from the researcher to ensure they approached each task correctly and were prompted when necessary. Participants attended the clinic twice per week, each time completing 3–4 training session over a two hour period. The entire data collection phase lasted approximately eight weeks and both participants completed all exercises and all sessions in that period. 3.4. Participants Participant A, was a 62-year-old divorced man. A retired financial planner, he had previously been a successful football player at club, provincial and international level. When first seen in 2009, he reported an eighteen month history of gradual worsening of memory difficulties such as forgetting names and word-finding problems. Long-term memory was intact. Premorbidly, he described having a very good memory. He continued to drive regularly without incident, and there were no reported difficulties with orientation and navigation. He was independent in his ADL’s and managed his own finances and household tasks with-

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out reported difficulty. He managed two investment properties without assistance and was in the process of selling his house. He exercised three times a week, but complained of poor sleep. There were no reported problems with driving. Medical history included cervical spondylosis and insomnia. There was no known history of stroke, heart disease. During his playing career he reportedly suffered several episodes of concussion. There was no known family history of dementia. A nonsmoker he reported a history of heavy alcohol intake, especially during his football playing days. His current intake was reportedly between two to four standard drinks most days. When reviewed in 2011 he reported relying on a diary to remember appointments more heavily than he used to, but did not forget to enter information or to check it. Repeat neuropsychological testing indicated ongoing difficulties with memory and naming. Other cognitive functions such as attention, working memory, executive functions and visuospatial ability were normal for age, but not necessarily normal for him, notably on two tasks requiring cognitive flexibility. He was diagnosed with MCI – Multiple domain.

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cognitive flexibility. She was diagnosed with Mild Cognitive Impairment – Multiple Domain with concern that this may progress to Alzheimer’s disease. 4. Results 4.1. Baseline Inspection of the baseline data revealed fluctuations in performance but no significant change across baseline for either participant. 4.2. Performance on treatment probes Data on the response of both participants to treatment as training progressed are presented in Figs. 1–4 below. There were fluctuations in performance at each session with a trend apparent over the course of training on probe measures of divided attention, and visual abstract reasoning across the baseline, phase 1 and phase 2 of training. However, a probe of visual memory (Paired Associates) did not show similar gains once Phase Two of training commenced.

3.5. Participant B The second participant was a 65 year-old woman, who was a retired teacher. She was referred in July 2011 after a clinic appointment with the Geriatric Community Registrar who noted a history of gradual decline in her memory over the past few years, including forgetting conversations, names, and dates. When interviewed, she said that she was not initially as aware of any memory problems as others appeared to be, but that her concern regarding her memory had increased in the last year. She continued to function independently, driving, using public transport, managing her finances and attending lectures and courses. Her medical history was largely unremarkable. She had been on hormone-replacement therapy since her hysterectomy some fifteen years earlier. She denied any history of head injury, or stroke but there was a family history of dementia with her mother being diagnosed with Alzheimer’s disease when aged in her 70’s. Earlier investigations in 2005 (neuropsychological testing and CT brain imaging) had been reported as normal for age. Neuropsychological testing in 2011 revealed impairment across a number of cognitive domains with poor retention of information over time without prompts or reminders. Other areas of concern included attenuated attention and working memory, processing speed, and

5. Regression analyses Linear regression analysis was then performed on measures that appeared to show a trend during training. For each of these probes, the average from the baseline data was used as the first data point in the analysis, with a total of 13 observations included in the analysis. The results indicated that for Participant A there was a significant change across training on a measure of attention (Trails A) and on a reasoning task (Odd One Out). A measure of divided attention (Trails B) was not significant. For Participant B none of the probe measures showed a significant change on this analysis.

6. Secondary outcome measures: Self-reported memory functioning and mood Both participants reported less cognitive failures and improved mood in everyday life as measured by the Cognitive Failures Questionnaire and DASS21 (see Figs. 5 and 6). Participant A’s overall number of selfreported cognitive failures on the CFQ was similar at baseline and post-treatment but there was a decrease in how often cognitive failures occurred.

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Fig. 1. Trails A time to completion during baseline and training phases. Lower scores indicate improvement. For all figures Participant A commenced training after completion of session 4. Phase One of training ran from session 5–10. Phase Two of training ran from session 11–16. Participant B Baseline ran from session 1–6. Phase One of training ran from session 7–12. Phase Two of training ran from session 13–18.

Fig. 2. Trails B time to completion during baseline and training phases. Lower scores indicate improvement.

Table 1 Treatment probes: Linear regression analysis Participant A Trails A Trails B Odd One Out Participant B Trails A Trails B Odd One Out

R Square

F

P value

0.349 0.276 0.348

5.89 3.05 5.88

0.03∗ 0.11 0.03∗

0.087 0.166 0.145

1.05 2.18 1.86

0.32 0.16 0.19

7. Discussion This research describes a novel method of assessing the impact of cognitive training using a single case design. Two older participants with Multiple domain MCI were given repeated practice on computerised cognitive exercises over a two month period. Both participants were able to engage with and complete the training, and improved across a range of trained tasks. The response to training was also reflected in

Fig. 3. Odd One Out scores during baseline and training phases. Higher scores indicate improvement.

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Fig. 4. Paired Associates scores during baseline and training phases. Higher scores indicate improvement.

Fig. 6. Self-reported depression, anxiety and stress symptoms for each participant at pre and post-training.

Fig. 5. Cognitive failures questionnaire data for each participant at pre and post-training.

improved mood and reduced self-reported cognitive failures following training. In terms of transfer from the training exercises to probe measures of cognition, both participants provided some evidence that the training benefitted cognition in general with improvements in visual abstract reasoning and divided attention. The study also provides some support for the findings reported by the authors (Finn & McDonald, 2011) which found an improvement in visual sustained attention following cognitive training. Attention is a fundamental cognitive skill (Hauke, Fimm & Sturm, 2011) and is typically preserved in Amnestic MCI. As attention is required across all the training tasks it is possible that it is the first domain to show effects when measured this way. Enhanced attention may serve as a foundation stone to allow other skills (such as complex executive functions) that are crucial in maintaining functional independence to be trained. However, in these Amnestic MCI participants, the training did not appear to generalise to a measure of immediate visual memory, a finding consistent both with our earlier study and with a reanalysis (Unverzagt et al., 2007) of the ACTIVE study data (Ball et al., 2002; Willis et al., 2006) showing that memory-impaired participants did not benefit from memory training, but did

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show a benefit from reasoning and processing speed training. This suggests that for people with Amnestic – MCI cognitive training may be beneficial in cognitive domains such as attention and cognitive flexibility but less so in terms of memory.

8. Limitations As a single case study, there are several limitations that should be acknowledged. First, the results apply to the participants and cannot be presumed to generalise to other participants, indeed the response to the training program varied across the two participants, underlining the heterogeneous nature of MCI in a clinical setting. Second, there was also variability in the data due to sources other than training. The variability observed in treatment response during each phase of training is to be expected when a SCED design is used for a non-behavioural treatment (McMillan & Morley, 2010) as this design is more open to the influence of extraneous variables. For example, there is some evidence that scores on the probes tended to worsen when the first phase of training commenced, possibly due to increased cognitive load, fatigue and initial confusion. Third, the intervention was intensive and delivered under near ideal conditions, making its application in a clinical setting in its current form doubtful. Fourth, the gains were relatively modest and restricted to nonmemory domains. The severe and often progressive amnestic difficulties in MCI are formidable obstacles, and in this study, measurable, reliable gains in memory were not seen. Because of these difficulties, a focus on executive functions may prove more fruitful in enhancing everyday functioning, and maintaining functional independence rather than attempting to enhance memory directly. Finally, the visual analysis used here is a common means of determining change in SCED but relying on visual inspection alone can result in ambiguous findings. An alternative approach would have been to perform a critical difference analysis (for example, Hauke, Fimm & Sturm, 2011), however reliability estimates and standard norms were not available for the probe measures used. Instead, visual inspection of the data was supplemented by linear regression using the average of the baseline. The drawback to this approach is that averaging masks real intra-subject variability. Further, linear regression for a data set of this size can be criticised as relatively few data points were available for the analysis, making the results sensitive to baseline values. To check that the results were not simply an arte-

fact of the baseline average, the regression analyses for the two probes with significant results (Participant 1: Trails A and Odd One Out) were re-run substituting the baseline average with each value obtained in the baseline data set, (a total of four additional analyses for Trails A and three for Odd One Out). This further analysis found significant or near significant (p < 0.10) results for both probes on six of the seven analyses, strengthening the conclusion that these measures were improving as training progressed. 8.1. Future directions This study has demonstrated the use of a SCED in an intervention study with repeated measures of cognition. Research into cognitive training remains at an early stage and a range of interventions will be trialled over the coming years. While RCT’s are useful to establish the efficacy of previously piloted interventions, they are expensive and may take some time to recruit adequate numbers of MCI participants. For novel interventions, SCED designs can be used to iron-out potential problems before proceeding to a larger trial. Where a larger trial has been conducted but with ambiguous results, SCED designs provide a relatively quick way of trialling modifications to the original research protocol. We hope that fellow researchers will find this approach to single case research in MCI useful and will not only adapt and modify it but use it as a spur to develop their own interventions. Appendix one The following descriptions of the training exercises are adapted versions of information provided by Lumosity Inc. Birdwatching: The silhouette of a bird appears briefly (initial exposure time 400 ms) somewhere on the screen while simultaneously a letter of the alphabet appears for the same duration in a small box in the centre of the screen. The participant has to firstly click on the area where the bird appeared and, if correct, is then asked to choose which letter appeared from a choice of five alternatives. The exercise commences at level one with a maximum of ten possible levels. Once the participant reaches a certain threshold level of performance, both the duration of exposure and the location of the bird stimulus are varied, with decreasing exposure time and more distance between the bird stimulus and the letter stimulus in the centre of the screen. These parameters change systematically at each level.

M. Finn and S. McDonald / Single case design cognitive training mild cognitive impairment

Lost in migration: A graphical depiction of a flock of five birds appears. The participant has to press the arrow key that corresponds to the direction of the bird in the centre of the flock. The direction of the central bird can be either the same of those of the other birds or different. The task is to get as many correct as possible in a 45 second period. Colour Match: Two words appear adjacent to each other on the screen, each of which is a colour. Participants have to identify if the meaning of the word on the left hand side matches the ink colour of the word on the right hand side. The task is to give the correct answer as many times as possible in a 45 second period. Brain Shift: This game requires the participant to switch rapidly between two different tasks. Two cards are presented on the screen. On each trial, a number and a letter appear on one of the cards. If the stimulus appears on the top card, then the participant should indicate “yes” if the number is even and “no” if the card is odd. On the other hand, if the stimulus appears on the bottom card, the participant should indicate “yes” if the letter is a vowel and “no” if the letter is a consonant. After a number of correct responses, the challenge is increased by removing the prompt explaining the rules; thus, the participant must remember the rules while accurately and rapidly indicating responses. Raindrops: Simple arithmetical equations appear inside droplets that fall from the top of the screen towards the bottom. The participant has to enter the correct answer before the droplet reaches the water at the bottom the screen. As the participant solves more equations, the droplets fall towards the bottom of the screen at increasing speed. The task continues until three droplets reach the water at the bottom of the screen. In Phase two of the training the following exercises were introduced and made up 50% of the training (the remaining 50% was the exercises listed above, rotated through the sessions in such a way that each exercise was used approximately the same number of times). Memory Matrix: In memory matrix, participants exercise their spatial working memory by remembering the location of squares on a grid. The target squares are presented one-at-a-time, and the participant must remember the location of all of the target squares and click on them at the end of the presentation. Initially, only three squares are presented, and the grid size is 3 × 3. However, with each correct response, the number of targets is increased by one, and the grid size grows as well. Each time an incorrect response is made,

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the number of targets reduced by one and the grid size shrinks. Monster Garden: This task is a visual working memory exercise that challenges the participant to remember the location of several obstacles that are presented only briefly. The participant has the additional challenge of maintaining the locations of the obstacles in working memory while navigating the game environment. The context of the game is a garden scene that is divided into a grid pattern. Initially, the participant is presented with an empty grid. Then, obstacles in the form of cartoon monsters appear briefly in various squares throughout the grid. The obstacles are presented such that only one is visible at a time. Next, a flower appears in one of the squares. The flower stays visible while the participant attempts to navigate the character through the garden by stepping only on open squares and avoiding squares where obstacles have appeared. If the participant achieves a score above criterion for that level, then the game is advanced to the next level upon the next round of play. There are 6 levels with increasing difficulty. At the easiest level, the grid is 4 × 4. At the highest level, the grid is 5 × 5. Difficulty is increased within a grid size by increasing the number of obstacles to be remembered. Familiar Faces: The game Familiar Faces challenges the ability to create associations between visual and verbal information, such as associating a person’s name with their face. The task in this exercise is to work as a server at a seaside restaurant. Each visitor has a name and places an order. The participant must remember the orders as well as the customers’ names to earn large tips. This game is an exercise of associative memory that is closely related to the kinds of memory challenges that are experienced on a daily basis. As performance improves on this task, more characters and more complicated orders are presented. Not only does the participant need to remember names during a single session, the participant must also remember names from past sessions, mimicking the real life situation.

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