Poor Memory Ability Research Articles

Cognitive offloading is value-based decision making: Modelling cognitive effort and the expected value of memory

How do people decide between maintaining information in short-term memory or offloading it to external reminders? How does this affect subsequent memory? This article presents a simple computational model based on two principles: A) items stored in brain-based memory occupy its limited capacity, generating an opportunity cost; B) reminders incur a small physical-action cost, but capacity is effectively unlimited. These costs are balanced against the value of remembering, which determines the optimal strategy. Simulations reproduce many empirical findings, including: 1) preferential offloading of high-value items; 2) increased offloading at higher memory loads; 3) offloading can cause forgetting of offloaded items (‘Google effect’) but 4) improved memory for other items (‘saving-enhanced memory’); 5) reduced saving-enhanced-memory effect when reminders are unreliable; 6) influence of item-value: people may preferentially offload high-value items and store additional low-value items in brain-based memory; 7) greatest sensitivity to the effort of reminder-setting at intermediate rather than highest/lowest levels of task difficulty; 8) increased offloading in individuals with poorer memory ability. Therefore, value-based decision-making provides a simple unifying account of many cognitive offloading phenomena. These results are consistent with an opportunity-cost model of cognitive effort, which can explain why internal memory feels effortful but reminders do not.

The Links Between Ageism and the Age-Based Double Standard

There is an age-based double standard in how we evaluate memory failures by younger and older adults. Whereas younger adults’ forgetfulness is attributed to lack of effort or attention, older adults’ forgetfulness is attributed to lack of ability. Our goal was to replicate this phenomenon, and evaluate its links to benevolent and hostile ageism. To do so, we used a vignette paradigm in which younger and older participants read about a target person (who was a younger or older woman) who left a store without paying for a ring (which varied in price). Results showed that participants were more likely to attribute this to poor memory abilities when the target was an older adult. They were also more lenient in their ascribed punishments for the older adult targets. In addition, reading about an older adult target’s mistake was associated with subsequently higher endorsement of benevolent, but not hostile, ageist attitudes.

Iron Status is Associated with Mood, Cognition, and Functional Ability in Older Adults: A Cross-Sectional Study.

Several conditions are risk factors for iron deficiency (ID), some of which are highly prevalent in older individuals. Despite the amount of evidence pointing for a role of ID in cognition, mood and physical functional ability, the research addressing these associations in older individuals is still scarce. In the present study, 162 older community-dwelling individuals (29.53% classified as ID) were enrolled in a cross-sectional analysis and characterized regarding cognition, mood, functional ability, general nutritional intake and iron status. Assessment of iron status was performed using several blood biomarkers. Storage and erythropoiesis dimensions were positively associated with memory, along with an interaction (moderator effect) between iron storage and nutritional status. A more depressed mood was negatively associated with (iron) transport, transport saturation and erythropoiesis dimensions, and functional tiredness was positively associated with the erythropoiesis dimension. These observations indicate that lower iron status is associated with depressive mood, functional tiredness and poorer memory ability, with the latter moderated by nutritional status. These findings suggest that using iron as a continuous variable may be useful in finding associations with iron homeostasis, eventually missed when iron levels are considered within the usual classification groups.

Prefrontal–hippocampal functional connectivity encodes recognition memory and is impaired in intellectual disability

Down syndrome (DS) is the most common form of intellectual disability. The cognitive alterations in DS are thought to depend on brain regions critical for learning and memory such as the prefrontal cortex (PFC) and the hippocampus (HPC). Neuroimaging studies suggest that increased brain connectivity correlates with lower intelligence quotients (IQ) in individuals with DS; however, its contribution to cognitive impairment is unresolved. We recorded neural activity in the PFC and HPC of the trisomic Ts65Dn mouse model of DS during quiet wakefulness, natural sleep, and the performance of a memory test. During rest, trisomic mice showed increased theta oscillations and cross-frequency coupling in the PFC and HPC while prefrontal-hippocampal synchronization was strengthened, suggesting hypersynchronous local and cross-regional processing. During sleep, slow waves were reduced, and gamma oscillations amplified in Ts65Dn mice, likely reflecting prolonged light sleep. Moreover, hippocampal sharp-wave ripples were disrupted, which may have further contributed to deficient memory consolidation. Memory performance in euploid mice correlated strongly with functional connectivity measures that indicated a hippocampal control over memory acquisition and retrieval at theta and gamma frequencies, respectively. By contrast, trisomic mice exhibited poor memory abilities and disordered prefrontal-hippocampal functional connectivity. Memory performance and key neurophysiological alterations were rescued after 1 month of chronic administration of a green tea extract containing epigallocatequin-3-gallate (EGCG), which improves executive function in young adults with DS and Ts65Dn mice. Our findings suggest that abnormal prefrontal-hippocampal circuit dynamics are candidate neural mechanisms for memory impairment in DS.

Individual chronic mountain sickness symptom is an early warning sign of cognitive impairment

Objective: To investigate the relationship between various chronic mountain sickness (CMS) symptoms and cognitive performances and identify whether individual CMS symptom can be used as early warning signs of specific cognitive impairment in long-term high altitude migrators. Methods: A total of 287 workers living at an altitude of 3850 m for 1–5 years participated in the study. According to the International Qinghai CMS Diagnostic Criteria, a questionnaire survey was conducted to measure the existence and severity of 7 self-perceptible CMS symptoms in addition to hemoglobin (Hb) levels in the blood. Six neurobehavioral tests were then conducted to assess cognitive function, and physiological indices, including Pittsburgh Sleep Quality Index (PSQI) and arterial oxygen saturation were also measured. Results: Compared with a score of 0 for each CMS symptom, scores of 1–3 universally corresponded to impairment in some aspects of cognition. Moreover, the correlation analysis revealed that subjects with different CMS symptoms exhibited specific aspects of cognitive impairment. Cyanosis was associated with slower auditory and visual reactions, reduced motion agility and poor visual memory ability (R = =0.236, 0.261, 0.155, 0.221, P < 0.01). Sleep disturbance and excessive erythrocytosis were significantly correlated to poor memory ability (R = =0.206~0.251, P < 0.01), and the symptoms of headache were mainly associated with impaired motion agility (R = =0.266, P < 0.01). The results also indicated that Hb ≥ 200 g/L, SpO2 ≤ 88%, and PSQI scores ≥ 7, which correspond to excessive erythrocytosis, cyanosis and sleep disturbance symptoms respectively, predicted the decline of cognitive function. Conclusions: The characteristics of symptoms used in Qinghai CMS Score System were associated with specific cognitive impairments in long-term plateau migrators, which supported the usefulness of monitoring cognitive status using CMS-related symptoms for both CMS patients and non-CMS people at high altitude.

The impact of self-awareness and depression on subjective reports of memory, quality-of-life and satisfaction with life following TBI

Objective: To determine the relationship between self-awareness and depressive symptomatology with self-reports of memory, Quality-of-Life (QoL) and satisfaction with life in individuals with traumatic brain injury (TBI).Methods: Cross-sectional survey of 30 community dwelling adults, who sustained a TBI at least 1 year prior to study enrolment. Participants completed questionnaires to assess the constructs of depression, self-awareness, QoL, satisfaction with life and memory.Results: Symptoms of depression were significantly associated with self-reports of poor memory abilities, lower QoL and lower satisfaction with life. Additionally, higher levels of self-awareness were associated with lower ratings of QoL and reduced memory abilities and better strategy use regarding memory. However, when examining the contribution of each construct individually, depressive symptomatology, and not self-awareness, was significantly associated with subjective self-reports of memory, QoL and satisfaction with life.Conclusions: This pattern of relationships illustrates that, when a person has a low level of depressive symptoms, his/her reports of QoL, memory and satisfaction with life will be more positive; however, he/she will demonstrate more difficulty with self-awareness. Thus, psychological aspects of recovery must, therefore, be taken into account when using self-reported measures in the evaluation of persons who have sustained TBI.

Individual differences in the effects of retrieval from long-term memory

The current study examined individual differences in the effects of retrieval from long-term memory (i.e., the testing effect). The effects of retrieving from memory make tested information more accessible for future retrieval attempts. Despite the broad applied ramifications of such a potent memorization technique there is a paucity of research tailored toward scrutinizing variability in the effect. Multiple measures of working memory capacity, attention control, episodic memory, and general-fluid intelligence were collected in addition to performance in a standard paired-associate testing task. A testing effect was observed and there was a great deal of individual variability in the magnitude of the effect. This variability was best accounted for by memory and intelligence constructs. Furthermore, the pattern of results is consistent with the notion that students with poor memory abilities and lower general-fluid intelligence benefit more so from testing memory than high ability students.

Episodic memory predictions in persons with amnestic and nonamnestic mild cognitive impairment

A performance-prediction paradigm was used to examine metamemory abilities in 27 individuals with amnestic mild cognitive impairment (MCI), 14 individuals with nonamnestic MCI, and 41 controls. To assess memory self-awareness, participants predicted the number of words they would remember before completing a list-learning memory task. Memory self-monitoring was evaluated by participants' ability to increase the accuracy of their predictions after experience with the list-learning task. As expected, participants with amnestic MCI demonstrated poorer memory abilities than the controls and participants with nonamnestic MCI. The amnestic MCI group also correctly predicted that they would recall less information than controls. Furthermore, both MCI groups showed accurate awareness of how differing task demands influence recall and successfully modified their memory predictions to be more accurate following task exposure. These findings revealed that individuals with amnestic and nonamnestic MCI were able to competently assess the demands of an externally driven metamemorial situation and utilize experience with a task to accurately update memory self-knowledge. Accurate metamemory skills may facilitate the ability of individuals with MCI to benefit from targeted behavioral interventions focused on utilizing compensatory strategies for everyday memory problems.

Perception of memory ability and confidence in recollections in obsessive-compulsive checking

Inconsistencies in research on deficits in memory for actions in studies of obsessive-compulsive (OC) checking have refocused investigators on beliefs such as confidence in the accuracy of recall as a possible motivation for checking. Poor confidence in relation to recall may be specific (perceived poor recall for a particular event) or general (perceived poor memory ability for that class of events). The present study examines both perception of memory ability and confidence in recollections in OC checkers across a range of situations, obsessive and non-obsessive. These ratings were compared with those of non-checking obsessional patients, anxious controls and non-clinical controls. OC checkers reported poorer perception of memory ability than other groups in situations for which they are responsible, both OC relevant and OC non-relevant. OC checkers also reported lower confidence in recollections compared to the other groups; this was specific to obsessional situations for which they are responsible. These findings are considered in the context of the cognitive model of OCD.

Memory and Anxiety in Prepubertal Boys at Risk for Delinquency

To examine the association between memory and anxiety symptoms in young urban-dwelling boys. A series of 111 boys, aged 7 to 11 years, at risk for disruptive psychopathology received standardized assessments of psychopathology and neuropsychological abilities, including verbal and design memory ability. While neuropsychological ability was rated at an initial study wave, psychopathology was rated at both an initial and a follow-up study wave, separated by approximately 18 months. Anxiety symptoms were more strongly correlated with poor memory ability than with reduced intelligence. Disruptive symptoms, in contrast, were more strongly correlated with reduced intelligence than with poor memory ability. Finally, boys with an anxiety disorder exhibited reduced memory abilities relative to other boys in the sample. Relationships generally appeared strongest in longitudinal analyses, such that poorer memory ability at study intake predicted increased anxiety at follow-up. Anxiety is associated with reduced memory ability in young urban boys at risk for disruptive psychopathology.