Brain function and behaviour related to development and training of working memory
Year: 2005
Type: dissertation
Abstract: Training of working memory (WM) is a research field that could result in \nnew therapeutic breakthroughs for people with impaired WM functions. In \nsupport of this view, research in our group has previously shown that WM \ntraining could increase WM capacity in children with attention deficits \nand in healthy adults. Apart from that study, there had been no previous \nliterature on WM training presenting clear evidence for a clinically \nrelevant change on WM capacity or brain activity following WM training. \nStudy II and III were designed to investigate these issues. \n \n \n \nOnly a few previous studies have investigated the development of brain \nactivity related to WM. The results from those previous studies indicate \nthat the development of WM is related to changes in activity in the \nfrontal and parietal cortex. The aim of the developmental studies in this \nthesis (Study I and IV) was to extend those previous findings using two \nnew approaches: 1) integration of data on brain function and brain \nstructure and 2) investigation of a critical WM function i.e. the ability \nto ignore distraction. \n \n \n \nPrevious research in our group showed that increased brain activity in \nprefrontal and parietal areas underlie the development of WM. In Study I, \nwe sought to investigate how this development is related to the \ndevelopment of brain connectivity. Our aim was to present a network of \nbrain structure and function underlying development of WM, which has \npreviously never been shown. Consistently, the results from Study I \nshowed that development of WM was related to a frontoparietal network of \nbrain regions where brain activity and connectivity showed a similar \ndevelopmental trend. \n \n \n \nThe published research on brain activity related to training of WM is \nvery scarce. Therefore, Study II aimed at investigating the long-term \neffects of WM training on brain activity using a training paradigm that \nwas designed to optimise the training effects for each individual. For \nthe first time we were able to show that training of a cognitive \nfunction, WM, could result in changes in brain activity in the adult \nhuman brain in task-related areas. \n \n \n \nIn Study III the aim was to establish whether WM training could result in \nclinically relevant effects on performance and behaviour such that it \ncould be used as a new therapy for groups of people with attention \ndeficits. The resulting analyses included data from 44 children, \ndiagnosed with ADHD, who had participated in a five week WM training \nprogram. Performance on executive functions, including WM, and \nbehavioural ratings of ADHD symptoms, improved significantly as an effect \nof WM training. \n \n \n \nIn Study IV we investigated the development of brain activity related to \nthe ability to ignore distraction. This ability is central to WM since \ndistracting stimuli must be ignored in order to keep information in WM. \nThere is no previous published research on the neural mechanisms \nunderlying the development of this important ability. The unravelling of \nthose mechanisms would add to the understanding of the neurobiology \nrelated to disorders affecting attention and impulsivity, in addition to \nincreasing our knowledge about WM functions. Furthermore, Study IV was \ndesigned to analyse developmental changes in brain activity related to \neach phase of a WM task. Importantly, we found that development of WM was \nrelated to increased brain activity in frontal and parietal areas during \nmaintenance of information in WM. The ability to ignore distraction was \nrelated to brain activity in the prefrontal cortex in adults. In children \nanother part of the prefrontal cortex was related to the presence of \ndistraction and this area corresponded to the area where information was \nmaintained. \n \n \n \nTo conclude, this thesis demonstrates previously unknown data on the \ncapacity of the human brain in relation to the healthy and deficient WM \nsystem and identifies brain areas that are crucial for the development of \nthis system.
Source: Figshare
Author: Jes Olesen
Language: English
Subfield: Experimental and Cognitive Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W2160891205