Working memory is critical for cognitive function and determines the efficiency of learning new skills. Our training aims to improve this cognitive performance while also considering the initial level of the trainee. By carefully designing procedures for experimental and active control groups, we have developed a training that incorporates the critical factor for determining the expected differences in training effectiveness.
Alexandra Bramorska, a PhD student from our lab will be demonstrating the procedure. Before beginning each procedure, give very clear and detailed instruction to the participants about how to perform each task. For an initial operation span task assessment, run a training block that automatically estimates the individual time needed for each participant to calculate a simple mathematical equation.
In the next training block display one letter on the screen at a time for 500 milliseconds per letter. After a full set of three to nine letters, present a matrix of 12 letters to the participant and have the participant click on the letters in the order that they were presented without a time limit. In the final block, combine the two training blocks presenting two to five equation letter pairs before displaying the letter matrix.
For running memory span task assessment, present information about the number of letters to be remembered in the task and to have the participants begin the task when they are ready. A sequence of letters should be presented in black font in the center of a white screen for about 0.25 seconds per letter. After each letter sequence, display a nine letter matrix on the screen and have the participant mark the appropriate letters in the order that they appeared without a time limit.
After confirming that the participant understands the task, have the participant repeat the task with the experimental sequence. For a switching task assessment, use a horizontal line to divide the screen into two parts and to present red squares or rectangles composed of smaller squares or rectangles above or below this line. Instruct the participant to click the left button and say rectangle when small figures are observed in the upper part of the screen.
And to click the right button and to say square when a whole figure composed from smaller figures is observed in the lower part of the screen. Then, display the figures above or below the middle line in random order. After completing the training block, have the participant perform the experimental task It is essential for participants to understand and comply with the training protocols.
Because without their comprehension, you cannot be sure what really influences their results. Before beginning either the experimental N-back or control quiz training, provide the participant with a login and password for the internet platform to allow the participant to enter the site only once every 24 hours to avoid situations in which the participant trains more than once a day. Explain to the participant that the initial level of N is two in the first block of the task.
And that the difficulty level may increase or decrease depending on the performance. Make clear that the whole session will last for 15 rounds with 20 plus end trials per round and that the whole training is set to 25 sessions. After explaining the task at level N equals two, use alphabet letters as auditory stimuli and green squares in one of nine locations in a three by three matrix as visual stimuli.
E.I.E.For a control quiz session, present 15 questions in each training session of the quiz task with no time limit for reading the questions. Instruct the participant to select one of the four given possibilities within 40 seconds of answering the question. In this representative experiment, 43 participants in the N-back training group and 42 in the quiz training group were analyzed.
Multivariate analysis of variants of the independent variables revealed statistically significant post-training improvement in the syllogisms and attention switching tasks. A significant training group effect was observed for the memory SPAN and OSPAN tasks. None of the interaction effects were proven to be statistically significant.
However, in the OSPAN task, the N-back training group improved their results in the second session while both performances were similar for the quiz group. The performances in the Sternberg's and go no go tasks were not related to a training group assignment or to the time of measurement. Multilevel analysis demonstrated that the OSPAN scores from the pre-training measurement were a significant predictor of the N-back outcome as starting from the first session participants with higher levels of OSPAN points had a much better performance of the N-back task throughout the training.
Since the training take place at home, it is essential for participants to understand and comply with the training protocols. Because without their comprehension you cannot be really sure what influences the results.
