Cognitive Exergame Training on Dual-Task Cost and Balance Stability in Older Adults

Limit of stability (LOS) is the amount of the maximum excursion of COP that can be achieved within the supported base without losing balance or taking a step. The dependent variable for LOS is COP parameters that will be collected separately for the (AP) and (ML) directions, such as the COP mean velocity, COP path and COP range (Juras et al. 2008).

Arithmetic cognitive tasks will be measured using the parameters of response latency and response accuracy. Response latency is defined as 'the time from stimulus onset to response onset', and response accuracy is defined as 'the number of correct responses divided by the total number of responses, expressed as a percentage. The cognitive task will only record at 80% of the correct responses or higher. This technique can help to identify if the cognitive task provides an adequate challenge for participants and minimize any learning effect.

FR will measure the maximal distance that can be reached forward beyond the arm's length, without moving the feet. A yardstick will be used to measure the forward reaching length in (cm).

The computerized visual search and detection test requires the disengagement from one focal area of attention to locate the next target (a triangle formed from constantly moving dots). The participant is instructed to press a key as soon as they could detect a triangle on the screen. The baseline level contained 15 stimuli, which are drawn in solid green lines on a black background. In the 40 complex-level stimuli, moving random dots covering the entire screen serve as background distractors. New target triangles are initially drawn with just a few visible dots of each line, and the density of these points increased linearly with time until a keypress response is registered. The screen is redrawn every 250 ms. After each response, new targets appear with random delays of at least 500 ms. Visual search results are recorded with reaction time (in ms) and the number of true and false positives.

The test is one of the most commonly used tests to measure the visuospatial short-term and working memory. This computerised test consists of nine cubical blocks positioned on the screen. The blocks are tapped in a specific sequence (the colour of tapped blocks change). The participant is asked to remember and tap these blocks in the same sequence. The sequences are easy at the beginning, usually involving three blocks, but they become more difficult in the later stages. The results are recorded with reaction time (in ms) and the number of true and false positives. The test takes around 5 mins.

Each form of the Hopkins Verbal Learning Test (HVLT) consists of a 12-item word list of four words from each of the three meaning categories. The participant is instructed to listen carefully as the assessor reads the word list and tries to memorize the words. The word list is then read to the subject at a rate of about one word every 2 seconds. The patient's free recall of the list is recorded. The same procedure is done for two more attempts. After the third learning attempt, the patient is read 24 words and asked to say "yes" after each word (12 goals) that appears on the recall list, and "no" after each word (12 distractors) that does not appear. Half of the distractors are taken from the same semantic categories as the targets (relevant distractors) and a half from other categories (unrelated distractors).

Timed up and go test (<3 min) The participant is asked to rise from a standard armchair, walk to a marker 3 m away, turn, walk back, and sit down again. The time is recorded.

The test measures the sensitivity to interference and the ability to suppress an automated response (time needed to read the colour words rather than the time it takes to name the colour of the letters). The baseline level contains 15 stimuli (reading colour names printed in white on a black background), the colour-interference level (naming the font colour rather than reading the printed colour name, which is always incongruent) comprise 40 stimuli.