Working-memory training in younger and older adults: training gains, transfer, and maintenance

Working memory (WM), a key determinant of many higher-order cognitive functions, declines in old age. Current research attempts to develop process-specific WM training procedures, which may lead to general cognitive improvement. Adaptivity of the training as well as the comparison of training gains to performance changes of an active control group are key factors in evaluating the effectiveness of a specific training program. In the present study, 55 younger adults (20–30 years of age) and 45 older adults (60–70 years of age) received 5 weeks of computerized training on various spatial and verbal WM tasks. Half of the sample received adaptive training (i.e., individually adjusted task difficulty), whereas the other half-worked on the same task material but on a low task difficulty level (active controls). Performance was assessed using criterion, near-transfer, and far-transfer tasks before training, after 5 weeks of intervention, as well as after a 3-month follow-up interval. Results indicate that (a) adaptive training generally led to larger training gains than low-level practice, (b) training and transfer gains were somewhat greater for younger than for older adults in some tasks, but comparable across age groups in other tasks, (c) far-transfer was observed to a test on sustained attention and for a self-rating scale on cognitive functioning in daily life for both young and old, and (d) training gains and transfer effects were maintained across the 3-month follow-up interval across age

Training-Induced Changes in Subsequent-Memory Effects: No Major Differences Among Children, Younger Adults, and Older Adults

The neural correlates of encoding mode, or the state of forming new memory episodes, have been found to change with age and mnemonic training. However, it is unclear whether neural correlates of encoding success, termed subsequent memory (SM) effects, also differ by age and mnemonic skill. In a multi-session training study, we investigated whether SM effects are altered by instruction and training in a mnemonic skill, and whether such alterations differ among children, younger adults, and older adults. Before and after strategy training, fMRI data were collected while participants were memorizing word pairs. In all age groups, participants receiving training showed greater performance gains than control group participants. Analysis of task-relevant regions showed training-induced reductions in SM effects in left frontal regions. Reductions in SM effects largely generalized across age, and primarily reflected greater training-induced activation increases for omissions than for remembered items, indicating that training resulted in more consistent use of the mnemonic strategy. The present results reveal no major age differences in SM effects in children, younger adults, and older adults

Neural Activation Patterns of Successful Episodic Encoding: Reorganization During Childhood, Maintenance in Old Age

The two-component framework of episodic memory (EM) development posits that the contributions of medial temporal lobe (MTL) and prefrontal cortex (PFC) to successful encoding differ across the lifespan. To test the framework’s hypotheses, we compared subsequent memory effects (SME) of 10-12 year-old children, younger adults, and older adults using functional magnetic resonance imaging (fMRI). Memory was probed by cued recall, and SME were defined as regional activation differences during encoding between subsequently correctly recalled versus omitted items. In MTL areas, children’s SME did not differ in magnitude from those of younger and older adults. In contrast, children’s SME in PFC were weaker than the corresponding SME in younger and older adults, in line with the hypothesis that PFC contributes less to successful encoding in childhood. Differences in SME between younger and older adults were negligible. The present results suggest that, among individuals with high memory functioning, the neural circuitry contributing to successful episodic encoding is reorganized from middle childhood to adulthood. Successful episodic encoding in later adulthood, however, is characterized by the ability to maintain the activation patterns that emerged in young adulthood

Effects of task information and active feedback control in inductive inference

Lindberg, L-Å., and Brehmer, B. Effects of task information and active feedback control in inductive inference. Umeå Psychological Reports No. 123, 1977. - Learning of an inductive task with one linear and one quadratic cue was investigated in a 2 (levels of task information: maximum vs. minimum) x 2 (control of outcome feedback: active vs.passive) x H (blocks of trials) factorial experiment. In the maximum information condition subjects were given the criterion distribution, including the mean, for each combination of cue values. Under the active feedback condition subjects selected cue combinations and feedback instances in whatever order they wanted. Positive effects of all three factors were obtained with respect to subjects'selection of inference rules and level of task control. It was concluded that subjects' inconsistency under ordinary outcome feedback conditions is due in part to lack of memory capacity and in part to the fact that subjects are prevented from active hypothesis testing. However,these factors do not fully explain the lack of consistency as shown by the fact that subjects under the present maximal information/active feedback condition did not reach the maximal level of task control, although they used the optimal inference rules.digitalisering@um

Omission of feedback in single-cue probability learning

Brehmer,B.,and Lindberg, L. Omission of feedback in single-cue probability learning. Umeå Psychological Reports, No. 46, 1971. - The effects of the omission of feedback in single-cue probability learning was studied as a function of the sign and magnitude of the correlation between cue and criterion variables, the magnitude of the slope relating the criterion values to the cue values, and the magnitude of the unaccounted for variance in the task in three experiments. Replicating earlier findings, the results of these experiments show that the omission of feedback results in an increase in the correlations between cues and judgments. This increase in correlations is due to an increase in the slopes of the regression lines relating the subjects' judgments to the cue values.digitalisering@um

Subjects' selection of feedback information in an inductive inference task

Lindberg, L-Å.,and Brehmer, B. Subjects' selection of feedback information in an inductive inference task. Umeå Psychological Reports No. 122, 1977. - Subjects' selection of outcome feedback instances in a probabilistic inference task with one linear and one nonlinear cue was investigated in a 2 (levels of task information: maximum vs. minimum) x 4 (blocks of trials) factorial experiment. Maximal information included the criterion distribution for each cue combination as well as aids for recording feedback instances, while minimal information consisted of standard instructions and no memory aids. Under both information conditions, subjects (1) examined one cue at a time, (2) gave priority to the more difficult quadratic cue, and (3) systematically changed their distribution and order of selections as a function of blocks.That is, subjects used the feedback infornation in a way that is not possible in the standard experimenter controlled reception paradigm. Furthermore, subjects made consequtive selections of the same cue combination more frequently in the maximum information condition that in the minimum information condition. These results are consistent with the assumptions that subjects under both conditions try to find the functional parameters of the task by means of a hypothesis testing activity, and that they learn to eliminate incorrect hypotheses with practice.digitalisering@um

Progression and hypothesis testing in an inductive inference task

Lindberg, L-Å., & Brehmer, B. Progression and hypothesis testing in an inductive inference task. Umeå Psychological Reports No. 121, 1977. - Subjects performance in a two-cue inference task was studied in three experiments as a function of (1) relative cue complexity, (2) relative cue validity, (3) task predictability, and (4) cue-criterion function form.Cues were defined through the velocity (more complex) and starting position (less complex) of a moving light spot. Results indicate that while relative cue complexity does not affect performance, the statistical structure of the task determines subjects' relative cue weighting as well as the final level of task control. These results contradict the Progression hypothesis, formulated for perceptual-motor skill development in tracking, and are consistent with earlier studies within the regression-correlation paradigm.digitalisering@um

Effects of task information and active feedback control in inductive inference

Lindberg, L-Å., and Brehmer, B. Effects of task information and active feedback control in inductive inference. Umeå Psychological Reports No. 123, 1977. - Learning of an inductive task with one linear and one quadratic cue was investigated in a 2 (levels of task information: maximum vs. minimum) x 2 (control of outcome feedback: active vs.passive) x H (blocks of trials) factorial experiment. In the maximum information condition subjects were given the criterion distribution, including the mean, for each combination of cue values. Under the active feedback condition subjects selected cue combinations and feedback instances in whatever order they wanted. Positive effects of all three factors were obtained with respect to subjects'selection of inference rules and level of task control. It was concluded that subjects' inconsistency under ordinary outcome feedback conditions is due in part to lack of memory capacity and in part to the fact that subjects are prevented from active hypothesis testing. However,these factors do not fully explain the lack of consistency as shown by the fact that subjects under the present maximal information/active feedback condition did not reach the maximal level of task control, although they used the optimal inference rules.digitalisering@um

No Evidence for Improved Associative Memory Performance Following Process-Based Associative Memory Training in Older Adults

Studies attempting to improve episodic memory performance with strategy instructions and training have had limited success in older adults: their training gains are limited in comparison to those of younger adults and do not generalize to untrained tasks and contexts. This limited success has been partly attributed to age-related impairments in associative binding of information into coherent episodes. We therefore investigated potential training and transfer effects of process-based associative memory training (i.e., repeated practice). Thirty-nine older adults (Mage = 68.8) underwent 6 weeks of either adaptive associative memory training or item recognition training. Both groups improved performance in item memory, spatial memory (object-context binding) and reasoning. A disproportionate effect of associative memory training was only observed for item memory, whereas no training-related performance changes were observed for associative memory. Self-reported strategies showed no signs of spontaneous development of memory-enhancing associative memory strategies. Hence, the results do not support the hypothesis that process-based associative memory training leads to higher associative memory performance in older adults