Goghari, VinaCampbell, TavisClark, Cameron2017-02-022017-02-0220172017Clark, C. (2017). On the Malleability of Human Cognition: Working Memory Training and Transfer (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/27193http://hdl.handle.net/11023/3642Training working memory (WM) to increase WM capacity and fluid intelligence (Gf) has received much experimental attention in recent years, though its efficacy remains highly controversial. The current study investigated the effect of a randomized six-week online WM intervention on cognitive abilities and patterns of neural activation in a community-recruited sample of healthy young adults, in relation to both a processing speed training active control condition, as well as a no-contact control condition. Results of this randomized trial are discussed in three parts: Chapter 2 examines group-level fMRI activation patterns for tasks of WM and Gf before the training intervention. Consistent with previous research, results indicate large areas of fronto-parietal activation in response to increasing task demands for our WM task, which largely subsume more circumscribed regions of activation for our Gf task. These results are discussed in terms of a task-general central network which may underlie performance of WM, Gf, and perhaps even goal-directed behaviour more generally. Chapter 3 investigates potential differences in a wide range of cognitive test scores before and after WM training, processing speed training, or no-contact. Results revealed support for the null hypothesis across all cognitive tests administered. Because these results are consistent with experimental trials of equal or greater methodological rigor, we suggest that future research re-focus on promising interventions known to increase memory performance in healthy young adults; and/or examine alternative populations in which WM training may be efficacious. Chapter 4 examines potential differences in pre- and post-training patterns of neural activation for WM and Gf tasks in our WM training, and processing speed training groups. Results indicated significant post-training reductions in activation for the WM trained group in relation to the processing speed group for the WM task, but not the Gf task. These results suggest that WM training does not affect patterns of neural activation for Gf tasks. We suggest that future research investigate neural correlates of WM training in populations for which WM itself is impaired; and/or WM training interventions in populations that have returned more promising results compared to those with healthy young adults.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Psychology--BehavioralPsychology--ClinicalPsychology--CognitivePsychology--ExperimentalPsychometricscognitive trainingWorking Memoryworking memory trainingfluid intelligenceintelligencereasoningnear-transferfar-transferfMRIdoctoral thesis10.11575/PRISM/27193