Significant Improvement In Memory Performance Research Articles

Application of Multi-Input Multi-Output Brain-Computer Interface in Cognitive Assessment for Alzheimer’s Disease

This research aims to augment human cognitive abilities, particularly memory function, through the development of innovative prosthetics. The hippocampus, a crucial brain region involved in memory encoding and recall, has been the focal point of numerous studies seeking to develop prosthetics that can restore or enhance memory function in individuals with impairments such as Alzheimer’s disease. This review examines two studies that delve into the development and application of hippocampal neural prosthetics, highlighting the potential of these prosthetics to revolutionize the treatment of memory impairments. One study utilized static neural stimulation patterns to enhance memory for specific information content, while another developed a nonlinear Multiple Input Multiple Output (MIMO) dynamic model to predict and stimulate neural activity patterns during memory encoding. Both studies demonstrated significant improvements in memory performance. Additionally, this paper discusses the clinical significance and application prospects of hippocampal neural prosthetics, including the potential for implantable prosthetics and the widespread applicability of MIMO stimulation. Furthermore, the paper explores advanced modeling and classification techniques for neural ensembles and visual memory decoding, including Volterra-type hierarchical modeling, optimal multi-unit stimulation patterns, and a sparse classification model for decoding visual memories. Finally, the paper presents the implementation and evaluation of neural prosthesis systems, including an application-specific integrated circuit (ASIC) design for a hippocampal prosthesis and a high-performance, scalable system architecture for real-time estimation of neural activity. These advancements hold promise for future research and applications in neural prosthetics for memory enhancement.

Effects of an individual cognitive stimulation intervention on global cognition, memory, and executive function in older adults with mild to moderate Alzheimer's disease.

To determine the efficacy of a 12-week individual cognitive stimulation (iCS) intervention on global cognition, memory, and executive function of older adults with mild to moderate Alzheimer's disease (AD). Protocolized analysis using data from a multicenter, single-blind, randomized, parallel two-arm RCT of iCS for older adults with probable AD. A sample of 142 people with probable Alzheimer's disease attending 13 Portuguese institutions providing care and support services for older adults were selected. Intervention group (n = 72) received 24 iCS sessions, twice a week for 12 weeks. Control group (n = 70) maintained their activities as usual. Outcomes included global cognitive function (Mini-Mental State Examination, and Alzheimer's Disease Assessment Scale-Cognitive Subscale), memory (Memory Alteration Test, and Free and Cued Selective Reminding Test), and executive functioning (Frontal Assessment Battery). All participants were assessed at baseline (T0), after the intervention (T1), and 12 weeks follow-up (T2). The results showed significant improvements in memory performance at follow-up for the intervention group and greater stability in global cognition in the intervention relative to the control group. The current iCS protocol shows effectiveness in cognitive functioning in older adults with probable AD, particularly for memory upon completion of the intervention and at follow-up, adding further support to previous iCS studies showing similar results and to the effectiveness of the current intervention.

<i>Khaya grandifololia</i> Improves Cognition and Prevents Scopolamine-Induced Impairment of Brain Functions by Activating the Cholinergic and Antioxidant Systems in Rats

Alzheimer’s disease (AD) is a multifactorial, progressive neurodegenerative disorder with dementia and persistent impairment of cognitive functions as the main clinical characteristics. Although signs of progress are being made in developing AD therapy, there is no effective drug capable of stopping and/or slowing down the progression of the disease. We have previously indicated in an in vitro setting of AD that <i>Khaya grandifololia</i> (KG) crude extract possesses antioxidant, anti-inflammatory, and neuroprotective activities. In the current work, we have evaluated the activity of KG hydroethanolic (KG-HE) extract in preventing cognitive impairment and promoting memory improvement in vivo. Results from behavioral tests indicated a significant improvement in memory performance and a delay in depression-like behavior upon treatment of rats with KG-HE extract (5, 25, and 50 mg/kg) or donepezil (1 mg/kg) as standard. Because scopolamine (1 mg/kg) impaired cognitive performance in the tail suspension test, Morris Water Maze test, and Novelty Suppressed Feeding Test, KG-HE extract (5, 25, and 50 mg/kg) or donepezil (1 mg/kg) treatment prevented scopolamine-induced performance impairment. Moreover, both KG-HE extract (5, 25, and 50 mg/kg) and donepezil (1 mg/kg) prevented the scopolamine-induced cognitive impairment by inhibiting the acetylcholinesterase activity. In addition, the brain parameters of stress oxidation (SOD, CAT, and GSH) reduced by scopolamine treatment were regulated by the administration of KG-HE extract or the standard drug donepezil. An increase in the MDA level and the phosphatase activity both in the serum and brain due to scopolamine treatment was restored by the administration of KG-HE extract or donepezil. Taken together, these results suggest that KG-HE extract improves cognition and relieves the scopolamine-induced cognitive impairment via activation of the cholinergic and anti-oxidation systems in rats.

Mild Cognitive Impairment and Neurofeedback: A Randomized Controlled Trial.

Background and Objectives: Mild cognitive impairment (MCI) is often a precursor of dementia, and in particular of Alzheimer's Disease (AD) which is the most common cause of dementia. Individuals with amnestic MCI are several-fold more likely to develop AD than the general population. Therefore, MCI comprises a well-detectable, early stage time-point for therapeutic intervention and strategic prevention. Based on common electroencephalographical (EEG) pattern changes seen in individuals with MCI, we postulated that EEG-based neurofeedback could help improve the memory performance of patients with MCI. Memory performance is of particular importance in these patients, since memory decline is the most prominent symptom in most patients with MCI, and is the most predictive symptom for cognitive deterioration and the development of AD.Methods: In order to improve the memory performance of patients with MCI we used a system of EEG-based neurofeedback in an attempt to reverse alterations of the EEG that are known to be common in patients with MCI. Our protocol comprised the provision of positive feedback in order to enhance the activity level of the upper alpha band. Participants were divided to two groups receiving either neurofeedback training to enhance the upper alpha frequency (Experimental group) or random feedbacks (Sham group)Results: We witnessed a significant improvement in memory performance in subjects in the experimental group compared to those in the sham group. This improvement was maintained for at least 1 month.Conclusions: Neurofeedback may be a promising and affordable novel approach for treating the decline in memory witnessed in patients with MCI.

Resistance exercise improves cognitive and brain health in overweight older adults

AbstractBackgroundApproximately 50% of Canadian older adults over the age of 60 are overweight or obese (based on body mass index; BMI). Individuals with high BMI (≥25) often experience cognitive and brain deficits (e.g., impaired memory, cortical atrophy, reduced neural activation), and are at high risk of dementia. One promising lifestyle intervention that may improve these deficits is exercise. For example, 6 months of aerobic training has been found to improve cognitive and brain function in overweight older adults, however studies examining whether resistance training (RT) can produce comparable results in this population is limited.MethodWe conducted a 6‐month, thrice‐weekly randomized controlled trial of RT in overweight older adults. Twenty‐four participants aged 60‐80 (sedentary; BMI ≥25) were randomized into one of two groups: 1) progressive resistance (weight) training, or 2) balance and tone (BAT; control; stretching exercises). At pre‐ and post‐intervention (0 and 6 months, respectively), we measured associative memory performance during functional MRI, and obtained high resolution T1 weighted structural images from a 3T scanner.ResultSix months of RT showed significant improvements in memory performance (6.38% reduced error rate) compared to BAT. Similarly, structural imaging showed increased hippocampal volume for RT (+0.04%) as well as increased percent signal change (neural activation) in memory‐related brain regions of interest, including the hippocampus, parahippocampal gyrus, lingual gyrus, and medial temporal gyrus, suggesting improved functional brain health overtime.ConclusionOverall, our findings offer a feasible, cost‐efficient lifestyle intervention strategy to improve cognitive and brain health in overweight older adults.

TO004IMPACT OF RENAL TRANSPLANT ON COGNITIVE FUNCTION AMONG ESRD PATIENTS ON DIALYSIS

Abstract Background and Aims Kidney transplantation can help in mitigating neuropsychological (NP) impairments in end-stage renal disease (ESRD). Evidences have shown mixed responses on the the nature of cognitive function in patients who have undergone renal transplantation.Present study looked into the factors impacting cognitive domains and impact post transplant. Method 43 patients who were stable ESRD on thrice a week hemodialysis were investigated 6 months pre and post transplant using a battery of neurophysiological testing assessing attention–concentration, psychomotor ability and memory. Formal kinetic modelling of dialysis delivery ensured adequate renal replacement therapy. Transplant function was assessed on regular interval and following a stable graft function and on stable doses of immunosuppressive medication 6 months post transplant were reassessed Results Within-subject comparisons showed statistically significant improvement in memory performance after kidney transplant. Other NP measures (attention– concentration and psychomotor abilities) showed non-significant improvements. Normative comparisons showed NP impairments on dialysis, which were not apparent after transplant Conclusion These data demonstrate improvements in cognition following kidney TX and emphasize the reversibility of the memory problems evidenced in dialysis

Solution-Processed Wide-Bandgap Organic Semiconductor Nanostructures Arrays for Nonvolatile Organic Field-Effect Transistor Memory.

In this paper, the development of organic field-effect transistor (OFET) memory device based on isolated and ordered nanostructures (NSs) arrays of wide-bandgap (WBG) small-molecule organic semiconductor material [2-(9-(4-(octyloxy)phenyl)-9H-fluoren-2-yl)thiophene]3 (WG3 ) is reported. The WG3 NSs are prepared from phase separation by spin-coating blend solutions of WG3 /trimethylolpropane (TMP), and then introduced as charge storage elements for nonvolatile OFET memory devices. Compared to the OFET memory device with smooth WG3 film, the device based on WG3 NSs arrays exhibits significant improvements in memory performance including larger memory window (≈45 V), faster switching speed (≈1 s), stable retention capability (>104 s), and reliable switching properties. A quantitative study of the WG3 NSs morphology reveals that enhanced memory performance is attributed to the improved charge trapping/charge-exciton annihilation efficiency induced by increased contact area between the WG3 NSs and pentacene layer. This versatile solution-processing approach to preparing WG3 NSs arrays as charge trapping sites allows for fabrication of high-performance nonvolatile OFET memory devices, which could be applicable to a wide range of WBG organic semiconductor materials.

Strategy for Semantic Association Memory (SESAME) training: Effects on brain functioning in schizophrenia

Self-initiation of semantic encoding strategies is impoverished in schizophrenia and contributes to memory impairments. Recently, we observed that following a brief training, schizophrenia patients had the potential to increase the self-initiation of these strategies. In this study, we investigated the neural correlates underlying such memory improvements.Fifteen schizophrenia patients with deficits in self-initiation of semantic encoding strategies were enrolled in a Strategy for Semantic Association Memory (SESAME) training. Patients underwent a memory task in an fMRI scanner. Memory performance and brain activity during the task were measured pre- and post- training, and changes following training were assessed. We also investigated if structural preservation measured by the cortical thickness of the left dorsolateral prefrontal cortex (DLPFC) predicted memory improvement post-training.Memory training led to significant improvements in memory performance that were associated with increased activity in the left DLPFC, during a task in which patients needed to self-initiate semantic encoding strategies. Furthermore, patients with more cortical reserve in their left DLPFC showed greater memory improvement.Our findings provide evidence of neural malleability in the left DLPFC in schizophrenia using cognitive strategies training. Moreover, the brain-behavioural changes observed in schizophrenia provide hope that memory performance can be improved with a brief intervention.

Physical Exercise and Brain Functions in Older Adults

Studies suggest that regular physical activity can help maintain and enhance brain functions in older adults. However, we still do not understand how physical activity impacts the rate of cognitive decline. One major issue is whether physical activity broadly defined (i.e., activity that is part of one's daily life involving bodily movements and the use of skeletal muscles) or structured exercise (i.e., physical activity that is planned, structured, and purposive to improve physical fitness) leads to the same benefits in preventing age-related cognitive decline. More studies are needed to appreciate the level of change or protection provided by physical activity, the basic mechanisms by which this change occurs, and whether physical activity can be beneficial despite chronic medical conditions and neurological or geriatric syndromes. This special issue presents original research results that bring additional support to the notion that physical exercise is an efficient nonpharmaceutical approach that can be used to enhance and maintain cognitive functions in healthy older adults and patients suffering from mild cognitive impairment. In a paper, we propose a brief review of the main impacts of exercise on cognition in older adults, frail patients, and those with mild cognitive impairment and dementia. Another paper of this special issue brings important knowledge in this regard. L. S. Nagamatsu et al. showed that physical activity helps improve verbal and spatial memory in older adults with probable mild cognitive impairment. In this study, eighty-six women aged 70–80 years with subjective memory complaints completed one of three interventions for 6 months: resistance training, aerobic training, or balance and tone (control). Both exercise groups showed significant improvements in memory performance, which was not observed in controls. An original study of this special issue explored the benefits of swimming on cognition in older adults. A. Abou-Dest et al. compared three groups of sixteen volunteer participants (young adults, sedentary older adults, and older adults who regularly practice swimming) on a battery of cognitive tasks. They reported that in older adults, regular swimming was related to better performance on executive functions but not on information processing speed. The selective benefit of exercise on executive control tasks was also reported after only 3 months of exercise intervention in a study of this special issue by D. Predovan et al. compared to controls, the training group showed significant improvements in physical capacity and enhanced Stroop performance, but only in the inhibition/switching condition, and the increase in aerobic capacity induced by the training regimen correlated negatively with reaction time in the inhibition/switching condition of the Stroop task at posttest. Importantly, the reported gains in cognitive performance were observed after only three months of physical training. The complex interaction between bodily exercise and cognition also calls into question the impact that mobility and gait might have on cognition in older adults. P. Plummer-D'Amato et al. addressed this issue in a contribution to this special issue. Studying how gait difficulty and cognitive task difficulty impact cognitive-motor interference in aging, they showed that gait task difficulty influences dual-task effects on gait speed, especially in older adults, and that this effect is influenced by the difficulty of the cognitive task. Another paper of the special issue brings up important issues on the potential moderators of physical activity on brain functions. R. L. Leckie et al. demonstrated how genes (APOE, BDNF, and COMT) along with dietary omega-3 fatty acid and docosahexaenoic acid (DHA) are potential moderators of the effect of physical activity on brain health. R. L. Leckie et al.'s proposal calls for further studies on the role of genes and dietary factors in the relationship between physical exercise and cognitive functions in older adults populations. All together, the studies published in this special issue bring additional scientific support to the notion that physical activity and exercise are a promising approach to alleviate the age-related impact on the body and mind. By doing so, they also support the promotion of health policies that should target inactivity in individuals of all ages and with any medical condition who are able to safely participate in physical activity.

Spatially Resolved Raman Spectroelectrochemistry of Solid-State Polythiophene/Viologen Memory Devices

A three terminal molecular memory device was monitored with in situ Raman spectroscopy during bias-induced switching between two metastable states having different conductivity. The device structure is similar to that of a polythiophene field effect transistor, but ethylviologen perchlorate was added to provide a redox counter-reaction to accompany polythiophene redox reactions. The conductivity of the polythiophene layer was reversibly switched between high and low conductance states with a "write/erase" (W/E) bias, while a separate readout circuit monitored the polymer conductance. Raman spectroscopy revealed reversible polythiophene oxidation to its polaron form accompanied by a one-electron viologen reduction. "Write", "read", and "erase" operations were repeatable, with only minor degradation of response after 200 W/E cycles. The devices exhibited switching immediately after fabrication and did not require an "electroforming" step required in many types of memory devices. Spatially resolved Raman spectroscopy revealed polaron formation throughout the polymer layer, even away from the electrodes in the channel and drain regions, indicating that thiophene oxidation "propagates" by growth of the conducting polaron form away from the source electrode. The results definitively demonstrate concurrent redox reactions of both polythiophene and viologen in solid-state devices and correlate such reactions with device conductivity. The mechanism deduced from spectroscopic and electronic monitoring should guide significant improvements in memory performance.

Montelukast potentiates the protective effect of rofecoxib against kainic acid-induced cognitive dysfunction in rats

There is an evolving consensus that mild cognitive impairment (MCI) serves as a prodrome to Alzheimer's disease. Antioxidants and COX-2 (cyclo-oxygenase-2) inhibitors have also been reported to have beneficial effects against conditions of memory impairment. Newer drugs like cysteinyl leukotriene inhibitors have shown neuroprotective effect in animal models of ischemia. Thus, the present study purports to explore the potential role of montelukast (a cysteinyl leukotriene inhibitor) in concert with rofecoxib (COX-2 inhibitor) and caffeic acid (a 5-LOX inhibitor and potent antioxidant) against kainic acid induced cognitive dysfunction in rats. In the experimental protocol, kainic acid (0.4μg/2μl) in artificial cerebrospinal fluid (ACSF) was given intrahippocampally (CA3 region) to induce a condition similar to MCI. Memory performance was measured on days 10–14 and the locomotor activity was measured on days 1, 7 and 14. For estimation of biochemical, mitochondrial and histopathological parameters, animals were sacrificed on day 14, stored at −80°C and the estimation was done on the 15th day. The treatment groups consisting of montelukast (0.5 and 1mg/kg), rofecoxib (5 and 10mg/kg) and caffeic acid (5 and 10mg/kg) showed significant improvement in memory performance, oxidative stress parameters and mitochondrial function as compared to that of control (kainic acid treated), however, combination of montelukast with rofecoxib showed significant improvement in their protective effect. Thus the present study emphasizes the positive modulation of cysteinyl leukotriene receptor inhibition on COX (cyclooxygenase) and LOX (lipoxygenase) pathways in the control of the neuroinflammation in kainic acid induced cognitive dysfunction in rats.

Comparison of single vs. multiple administrations of the AMPA receptors modulator S 18986 in the object recognition task in rats

The present study aimed at defining the best scheme of administration of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-positive modulator (S)-2,3-dihydro-[3,4]-cyclopentano-1,2,4-benzothiadiazine-1,1-dioxide (S 18986) [once daily (o.d.) administration of 1 mg/kg for 3 days vs. three times daily (t.i.d.) administration of 0.3 mg/kg for 3 days] to get an optimal procognitive activity in the object recognition task in rats. Memory performance [Recognition Index (RI)] of rats was significantly improved 1 h (RI = 41%, P < 0.01) and 3 h (RI = 46%, P < 0.001) following oral administration of S 18986 (1 mg/kg, o.d.) when compared with animals receiving the vehicle (RI = 6%). When the interval between administration and testing was increased to 6 h and 9 h, no statistically significant improvement in memory performance was observed (RI = 42% for 6 h and RI = 18% for 9 h vs. 20% for the vehicle group). When S 18986 was administered at 0.3 mg/kg t.i.d., no statistically significant improvement in memory performance was observed (RI = 36%). These findings show a long-lasting efficacy of the AMPA receptor allosteric modulator in the object recognition task despite a short half-life in plasma and in brain (approximately 1 h). Accordingly, multiple administrations of S 18986 are not required to obtain a maximal efficacy in this paradigm, because a o.d. schedule of administration leads to a powerful procognitive activity.

Cognitive functioning pre- to post-kidney transplantation--a prospective study

Kidney transplantation (TX) may ameliorate the neuropsychological (NP) impairments in end-stage renal disease (ESRD). Previous studies have suffered from small sample sizes, lack of standardization of dialysis adequacy, and insufficiently sensitive NP tests. Twenty-eight medically stable patients aged 44.04 (12.01) years with ESRD were investigated before and at 6 months after successful kidney TX using an NP test battery, which assessed attention-concentration, psychomotor ability and memory. Formal kinetic modelling of dialysis delivery ensured adequate renal replacement therapy. Transplant function was good on stable doses of immunosuppressive medication, without evidence of rejection at the time of testing. Within-subject comparisons showed statistically significant improvement in memory performance after kidney TX. Other NP measures (attention-concentration and psychomotor abilities) showed non-significant improvements. Normative comparisons showed NP impairments on dialysis, which were not apparent after TX. These data demonstrate improvements in cognition following kidney TX and emphasize the reversibility of the memory problems evidenced in dialysis.

Donepezil improved memory in multiple sclerosis in a randomized clinical trial

To determine the effect of donepezil in treating memory and cognitive dysfunction in multiple sclerosis (MS). This single-center double-blind placebo-controlled clinical trial evaluated 69 MS patients with cognitive impairment who were randomly assigned to receive a 24-week treatment course of either donepezil (10 mg daily) or placebo. Patients underwent neuropsychological assessment at baseline and after 24 weeks of treatment. The primary outcome was change in verbal learning and memory on the Selective Reminding Test (SRT). Secondary outcomes included other tests of cognitive function, patient-reported change in memory, and clinician-reported impression of cognitive change. Donepezil-treated patients showed significant improvement in memory performance on the SRT compared to placebo (p = 0.043). The benefit of donepezil remained significant after controlling for various covariates including age, Expanded Disability Status Scale, baseline SRT score, reading ability, MS subtype, and sex. Donepezil-treated patients did not show significant improvements on other cognitive tests, but were more than twice as likely to report memory improvement than those in the placebo group (p = 0.006). The clinician also reported cognitive improvement in almost twice as many donepezil vs placebo patients (p = 0.036). No serious adverse events related to study medication occurred, although more donepezil (34.3%) than placebo (8.8%) subjects reported unusual/abnormal dreams (p = 0.010). Donepezil improved memory in MS patients with initial cognitive impairment in a single center clinical trial. A larger multicenter investigation of donepezil in MS is warranted in order to more definitively assess the efficacy of this intervention.

Oral Cerebrolysin enhances brain alpha activity and improves cognitive performance in elderly control subjects.

Cerebrolysin is a porcine brain derived peptide preparation with potential neurotrophic activity. The effects of a single oral dose of the Cerebrolysin solution (30 ml) on brain bioelectrical activity and on cognitive performance were investigated in healthy elderly people. A single oral dose of Cerebrolysin induced a progressive increase in relative alpha activity power from 1 to 6 hours after treatment in almost all the brain electrodes in elderly control subjects. As compared with baseline alpha power (45.8+/-9.5%), the increase in relative alpha activity in the left occipital electrode (O1) reached significant values at 1 hour (57.2+/-8.5%; p < 0.05), 3 hours (59.4+/-7.6%; p < 0.05) and 6 hours (63.4+/-9.8%; p < 0.05) after Cerebrolysin administration. Enhancement in relative alpha power was accompanied by a generalized decrease in slow delta activity that was maximum at 6 hours after Cerebrolysin intake. A significant improvement in memory performance, evaluated with items of the ADAS cog, was also found in elderly people taken a single dose of oral Cerebrolysin (6.9+/-1.0 errors at baseline versus 4.9+/-1.0 errors after treatment; p < 0.01). This memory improvement was more evident in recognition (2.8+/-0.6 errors vs. 1.5+/-0.7 errors; p < 0.05) than in recall tasks (4.1+/-0.5 errors versus 3.4+/-0.5 errors; ns). These data indicate that Cerebrolysin potentiates brain alpha activity, reduces slow EEG delta frequencies and improves memory performance in healthy elderly humans, suggesting that this compound activates cerebral mechanisms related to attention and memory processes. According to the present results, it seems that oral Cerebrolysin might be useful for the treatment of memory impairment and brain damage in eldely subjects with or without neurodegenerative disorders.

Treatment of Alcoholic Organic Brain Syndrome with the Serotonin Reuptake Inhibitor Fluvoxamine:

The chronic effects of fluvoxamine (200 mg per day for 4 weeks) were studied in ten alcoholic organic brain syndrome patients in a double-blind cross-over design. Complete neuropsychological evaluation was performed as well as measurement of neurochemical changes in CSF. Fluvoxamine produced a small but significant improvement in memory performance. An analysis of fluvoxamine minus placebo difference scores showed a significant correlation between memory functioning and CSF 5HIAA levels. Alcohol amnestic syndrome patients who had the highest blood levels of fluvoxamine demonstrated the largest changes in CSF 5HIAA and improvement in memory performance under fluvoxamine. These findings implicate a role of serotonergic mechanisms in alcoholic organic brain syndrome and suggest that with individual titration of the drug dose, fluvoxamine might be a clinically useful agent in the treatment of this syndrome.