Relationship between physical activity and specific working memory indicators of depressive symptoms in university students

BACKGROUND The detection rate of depression among university students has been increasing in recent years,becoming one of the main psychological diseases that endangers their physical and mental health.According to statistics,self-harm and suicide,for which there is no effective intervention,are the second leading causes of death.AIM To explore the relationship between different elements and levels of physical activity and college students’depression-symptom-specific working memory indicators.METHODS Of 143 college students were analyzed using the Beck Depression Self-Rating Scale,the Physical Activity Rating Scale,and the Working Memory Task.RESULTS There was a significant difference between college students with depressive symptoms and healthy college students in completing verbal and spatial working memory(SWM)tasks correctly(all P<0.01).Physical Activity Scale-3 scores were significantly and positively correlated with the correct rate of the verbal working memory task(r=0.166)and the correct rate of the SWM task(r=0.210)(all P<0.05).There were significant differences in the correct rates of verbal and SWM tasks according to different exercise intensities(all P<0.05)and different exercise durations(all P<0.05),and no significant differences in the correct rates of verbal and SWM tasks by exercise frequency(all P>0.05).CONCLUSION An increase in physical exercise among college students,particularly medium-and high-intensity exercise and exercise of 30 min or more,can improve the correct rate of completing working memory tasks.

Working Memory Function in Chinese Dyslexic Children:A Near-Infrared Spectroscopy Study

The deficiency theories of dyslexia are quite contradictory and the cross-cultural studies in recent years mainly focused on whether the dyslexics among cultures shared the same cognitive profile or just based on the language.This study used Near-Infrared Spectroscopy (NIRS) imaging to measure the regional cerebral blood volume (BV) and the changes of cerebral activation in the left prefrontal cortex of 12 Chinese dyslexic children and their 12 age-matched normal controls during the Paced Vis-ual Serial Addition Test (PVSAT).Results showed that the scores of PVSAT of dyslexic children were significantly lower than those of the normal children (t=3.33,P<0.01).The activations of the left pre-frontal cortex in the normal group were significantly greater than those of dyslexic children (all P<0.01).Our results indicated that Chinese dyslexia had a general deficiency in working memory and this may be caused by the abnormal metabolic activity of brain blood volume in the left prefrontal cortex and the deficits in brain function might be the basis of neuropathology of Chinese dyslexia.Present study sup-ports the difference on brain activation of dyslexics from different languages may be caused by the same cognitive system related to reading.

Low-level lead exposure effects on spatial reference memory and working memory in rats

BACKGROUND： Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions. OBJECTIVE： To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes. DESIGN AND SETTING： The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance （ANOVA） and behavioral observations were performed. MATERIALS： Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal con-trol and lead exposure groups （n = 8）. METHODS： Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases： space navigation, probe test, working memory test, and visual cue test. MAIN OUTCOME MEASURES： Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function. Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats. RESULTS： （1） In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups （F（1,1） = 0.007, P = 0.935）. A visible decrease in escape latencies was observed in each group （P = 0.028）. However, there was no significant difference between the two groups （F（1,1） = 1.869, P = 0.193）. The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test （F（1,1） = 1.869, P = 0.193）. However, by day 4, differences were observed in the working memory test （P 〈 0.01）. （2） Multivariate repetitive measure and ANOVA in place navigation presented no significant difference between the two groups （F（1,1） = 0.579, P = 0.459）. （3） Spatial probe test demonstrated that the time to reach the platform was significantly different between the two groups （F（1,1） = 4.587, P = 0.048）, and one-way ANOVA showed no significant difference in swimming speed between the two groups （F（1,1） = 1.528, P = 0.237）. （4） In the visual cue test, all rats reached the platform within 15 seconds, with no significant difference （F（1,1） = 0.579, P = 0.459）. （5） During experimentation, all rats increased in body mass, but there was no difference between the two groups （F（1,1） = 0.05, P = 0.943）. At day 28 of 0.05% lead exposure, the blood lead level was 29.72 μg/L in the lead exposure group and 5.86 μg/L in the control group （P 〈 0.01）. CONCLUSION： The present results revealed low-level lead exposure significantly impaired spatial reference memory and spatial working memory, but had no effect on spatial learning.

What emotion dimensions can affect working memory performance in healthy adults?A review

Due to the critical roles of emotion and working memory in our daily activities,a great deal of attention has been given to how emotion influences working memory performance.Although the association between emotion and working memory is relatively well established,whether mood enhances or impairs working memory performance remains controversial.The present review provides a relatively representative overview of the research on the effect of different dimensions of emotion on working memory among healthy adults spanning a 30-year period.The findings show that the valence,arousal and motivational dimensions of emotion could all exert an impact on working memory performance.The impact of emotion on working memory might be modulated by task relevance,emotion type,working memory paradigms and individual differences.The vast majority of the studies regarding the effect of emotion on working memory performance focused on the impact of negatively valenced affect and yielded highly contradictory findings.The impacts of arousal and motivation on working memory have been less explored,and inconsistent findings have also been reported.Possible explanations are discussed.Considerable research on the effect of certain dimensions of emotion on working memory has suffered from a lack of control of other emotional dimensions,and different aspects of working memory have been investigated by various paradigms.Directions for further studies should include the exploration of specific dimensions of emotion on different aspects of working memory,with the other dimensions being well controlled.

Role of hippocampal dentate gyrus neurons in the protective effects of heat shock factor 1 on working memory

Increasing evidence suggests that heat shock factor 1 exerts endogenous protective effects on working memory under conditions of chronic psychological stress. However, the precise underlying mechanisms remain poorly understood. This study examined the protective factors affecting working memory in heat shock transcription factor 1 gene knockout mice. The results indicated that the number of correct T maze alternations decreased following mild chronic psychological stress in knockout mice. This change was accompanied by a decrease in neurogenesis and an increase in neuronal apoptosis in the hippocampal dentate gyrus. The number of correct T maze alternations was positively correlated with neurogenesis in hippocampal dentate gyrus, and negatively correlated with neuronal apoptosis. In wild type mice, no significant difference was detected in the number of correct T maze alternations or neuronal apoptosis in hippocampal dentate gyrus. These results indicate that the heat shock factor 1 gene has an endogenous protective role in working memory during mild chronic psychological stress associated with dentate gyrus neuronal apoptosis Moreover, dentate gyrus neurogenesis appears to participate in the protective mechanism.

ASSESSING WORKING MEMORY IN REAL-LIFE SITUATIONS WITH FUNCTIONAL NEAR-INFRARED SPECTROSCOPY

Working memory is one of the most important functions in our brain,which has been widely studied with unreal-life measured technologies.A functional near-infrared spectroscopy(fNIRS)instrument with a portable and low-cost design is developed,which is capable of providing hemodynamic measurement associated with brain function in real-life situations.Using this instrument,we performed working memory studies involved in Chinese words encoding,verbal,and spatial stem recognition,which are mainly studied with other technologies.Our results show that fNIRS can well assess working memory activities,in comparison with the reported results mainly using other methodologies.Furthermore,we find that hemodynamic change in the prefrontal cortex during all working memory tasks is highly associated with subjects’behavioral data.fNIRS is shown to be a promising alternative to the current methodologies for studying or assessing functional brain activities in natural condition.

Relationship among Eating Behavior, Effortful Control, and Working Memory in Female Young Adults

The management of eating behavior plays an important role in health maintenance. In this study, we investigated the relationship between eating behavior and effortful control in female young adults. Participants completed the questionnaire measures of effortful control and eating behaviors and Stroop cognitive interference task. The results showed that restrained eating was positively correlated with activation control;emotional eating was negatively correlated with inhibitory control and attentional control;external eating was negatively correlated with inhibitory, activation, and attentional control. The scores for activation control and restrained eating were higher for participants with a low Stroop error rate than for those with a high Stroop error rate. These results indicate that restrained eating has a different association with effortful control than doing emotional and external eating.

EEG Correlations during a Working Memory Task with Emotional Stimuli in Girls with Post-Traumatic Stress Disorder Secondary to Sexual Abuse

Survivors of Child Sexual Abuse (CSA) can develop Post-Traumatic Stress Disorder (PTSD), alterations in the prefrontal cortex, changes in electroencephalographic (EEG) activity, and lower performance on working memory tasks. The aim of this study was to characterize brain electrical correlations in girls with PTSD secondary to CSA during a working memory task based on recognizing emotional facial stimuli. Girls aged 8 - 16 years old were evaluated: 12 with PTSD secondary to CSA, and 12 healthy girls with no history of abuse. EEG activity during a working memory task with emotional stimuli was recorded, and the inter- and intra-hemispheric correlations that assessed the functional connectivity among different cortical regions were analyzed. The PTSD group showed lower performance than controls on the working memory task while watching happy faces, while the EEG of this group showed greater intrahemispheric correlation among frontal areas and between frontal and posterior cortical regions. Also, the PTSD group had lower interhemispheric correlations between posterior temporal areas. The higher intrahemispheric correlation in the PTSD group could indicate that those girls used more brain areas when performing the task, likely because it required greater effort. The lower inter-posterior temporal correlation could be attributed to a reduction of the corpus callosum.

Reserpine Improves Working Memory

Despite exhaustive search, no drug is in sight for AD. Earlier, we reported that reserpine, an antihypertensive and antipsychotic drug, ameliorates Amyloid beta (Aβ-AD causing peptide) toxicity and confers several positive enhancements in the C. elegans model system. Here, we evaluate whether reserpine can provide protection against working memory and against AD in the mouse model. Reserpine (0.08 mg) was administered orally on alternate days to the non-Tg and accelerated Aβ deposition (at 2 months of age)and cognitive deficit (4 months of age) developing 5XFAD AD Tg mouse model expressing mutant human APP (3 familial mutations) and human Presenilin1(2 familial mutations) in the neurons, and follow their working memory for 2 months using the spontaneous Y-maze alteration behavioral paradigm. Reserpine enhanced working memory in non-Tg mice and improved the cognitive deficit in the 5XFAD AD Tg mice. Hence, reserpine can be considered for a detailed evaluation in the 3X Tg AD mouse model and a pilot study in AD patients.

Effects of Color on the Buildup and Resolution of Proactive Interference in Working Memory

The“color superiority effect”was confirmed by the research of color on forgetting,which showed that proactive interference(PI)has less impact on colored items than gray ones.Color could directly affect the buildup of PI,leading to reduced levels of interference,or controlled processes that resolve PI.However,the effects of red and green on memory were inconsistent.Using Recent-Probes task,the current study explored how the red and green color influenced to the buildup phase(i.e.,200ms after the onset of probe)and resolution phase(i.e.800ms after the onset of probe)of PI.Results revealed that the reaction times of green words were significantly shorter than the red words under 200ms.There were no significant differences between the red and green words under 500ms and 800ms.It indicated that green might shortened the reaction times for the PI buildup,while red prolonged it.However,on the resolution phase of PI,green words were less effective than red words.These findings offered some new information for the underlying mechanisms that modulate the interactions between color and memory.

Computerized Training of Working Memory for Patients with Acquired Brain Injury

Background: Patients with acquired brain injury often experience impaired working memory (WM), a condition that can make everyday life activities and work difficult. Objectives: This study investigates the effects of computerized WM training on WM skills, cognitive tests, activity performance and estimated health and whether the effects of computerized WM training can be attributed to sex or time since injury. Methods: Forty-eight patients with acquired brain injury underwent computerized WM training. Patients were tested by a neuropsychologist and interviewed by an occupational therapist just prior and 20 weeks after completion of training. Results: Patients who participated in computerized WM training significantly improved their WM skills shown in WM index, their neuropsychological test scores, and their self-estimated health scores. They also significantly improved their performance of individually defined WM-related everyday activities and their satisfaction with the performance of these activities. There was a significant difference in terms of WM index, WM-related daily activity performance, and satisfaction with respect to time since injury. Conclusion: Computerized WM training can improve cognitive and everyday performance for patients with acquired brain injury. Patients can improve their cognitive functions a long time after suffering a brain injury or disease. This effect is greater if WM training is used early in the rehabilitation.

A Study on the Correlation among FD-FI Cognitive Style,Working Memory Capacity and English Reading Performance among College EFL Learners

In the past few decades,there have been eminent interests in reading performance as essential means for language input.In view of that,extensive studies have been conducted to explore the factors that affect reading performance from various aspects.In the cognitive psychology field,some studies have examined the relationship between field dependent-field independent(FD-FI)cognitive styles and working memory capacity(WMC)on English reading,respectively.However,only limited studies focused on the correlation among FD-FI cognitive styles,WMC and English reading performance.Therefore,this study was conducted to explain these correlations.A total of 42 intermediate“English as Foreign Language”(EFL)learners participated in this study.In order to measure the learners’FD-FI cognitive style,WMC and English reading performance,the Cognitive Style Figures Test,reading span task and the International English Language Test System(IELTS)reading test were adopted,respectively.Data analyses such as Pearson’s correlation,independent sample t-test and two-way ANOVA were done using Statistical Package for the Social Science(SPSS)version 25.The results suggested a statistically significant correlation between FD-FI cognitive style and WM with English reading performance,respectively.The main effect of WM and FD-FI cognitive style is significant while the interaction between them is not significant in reading performance.

Influence of Working Memory Capacity on the Frequency of Self-Repairs

This article explored the influence of working memory capacity on the frequency of self-repairs.The narrative task and listening span task were used.Twenty post-graduate students participated in this study.Overall,the results of this study illustrated that the working memory is a factor of self-repairs.Speakers who have higher working memory capacity produce lesser self-repairs.This finding provides teachers with a new insight into second language teaching;that is,teachers can improve the amount of lexical knowledge when teaching students who have lower working memory in order to help them produce more accurate language during the process of L2 speech production.

Theta Oscillations Support Prefrontal-hippocampal Interactions in Sequential Working Memory

The prefrontal cortex and hippocampus may support sequential working memory beyond episodic memory and spatial navigation.This stereoelectroencephalography(SEEG)study investigated how the dorsolateral prefrontal cortex(DLPFC)interacts with the hippocampus in the online processing of sequential information.Twenty patients with epilepsy(eight women,age 27.6±8.2 years)completed a line ordering task with SEEG recordings over the DLPFC and the hippocampus.Participants showed longer thinking times and more recall errors when asked to arrange random lines clockwise(random trials)than to maintain ordered lines(ordered trials)before recalling the orientation of a particular line.First,the ordering-related increase in thinking time and recall error was associated with a transient theta power increase in the hippocampus and a sustained theta power increase in the DLPFC(3–10 Hz).In particular,the hippocampal theta power increase correlated with the memory precision of line orientation.Second,theta phase coherences between the DLPFC and hippocampus were enhanced for ordering,especially for more precisely memorized lines.Third,the theta band DLPFC→hippocampus influence was selectively enhanced for ordering,especially for more precisely memorized lines.This study suggests that theta oscillations may support DLPFC-hippocampal interactions in the online processing of sequential information.

Dorsolateral prefrontal cortex, working memory and episodic memory processes: insight through transcranial magnetic stimulation techniques

The ability to recall and recognize facts we experienced in the past is based on a complex mechanism in which several cerebral regions are implicated. Neuroimaging and lesion studies agree in identifying the frontal lobe as a crucial structure for memory processes, and in particular for working memory and episodic memory and their relationships. Furthermore, with the introduction of transcranial magnetic stimulation （TMS） a new way was proposed to investigate the relationships between brain correlates, memory functions and behavior. The aim of this review is to present the main findings that have emerged from experiments which used the TMS technique for memory analysis. They mainly focused on the role of the dorsolateral prefrontal cortex in memory process. Furthermore, we present state-of-the-art evidence supporting a possible use of TMS in the clinic. Specifically we focus on the treatment of memory deficits in depression and anxiety disorders.

Working-memory training improves developmental dyslexia in Chinese children

Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memory training. In the present study, thirty dyslexic children aged 8-11 years were recruited from an elementary school in Wuhan, China. They received working-memory training including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading.

Anticipatory activity in rat medial prefrontal cortex during a working memory task

Objective Working memory is a key cognitive function in which the prefrontal cortex plays a crucial role. This study aimed to show the firing patterns of a neuronal population in the prefrontal cortex of the rat in a working memory task and to explore how a neuronal ensemble encodes a working memory event. Methods Sprague-Dawley rats were trained in a Y-maze until they reached an 80% correct rate in a working memory task. Then a 16-channel microelectrode array was implanted in the prefrontal cortex. After recovery, neuronal population activity was recorded during the task, using the Cerebus data-acquisition system. Spatio-temporal trains of action potentials were obtained from the original neuronal population signals. Results During the Y-maze working memory task, some neurons showed significantly in- creased firing rates and evident neuronal ensemble activity. Moreover, the anticipatory activity was associated with the delayed alternate choice of the upcoming movement. In correct trials, the averaged pre-event firing rate （10.86 ± 1.82 spikes/ bin） was higher than the post-event rate （8.17 ± 1.15 spikes/bin） （P 〈0.05）. However, in incorrect trials, the rates did not differ. Conclusion The results indicate that the anticipatory activity of a neuronal ensemble in the prefrontal cortex may play a role in encoding working memory events.

The effect of acupuncture on mood and working memory in patients with depression and schizophrenia

BACKGROUND： In patients with depression, as well as in patients with schizophrenia, both mood and working memory performance are often impaired. Both issues can only be addressed and improved with medication to some extent. OBJECTIVE： This study investigates the mood and the working memory performance in patients with depression or schizophrenia and whether acupuncture can improve these. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS： A pragmatic clinical trial design was used The study was conducted in a psychiatric clinic. Fifty patients with depression and 50 with schizophrenia were randomly divided into an experimental and a waiting-list group. Additionally, 25 healthy control participants were included. Twelve weeks of individualized acupuncture treatment was used as the clinical intervention. MAIN OUTCOME MEASURES： All patients were tested before （T1） and after （T2） acupuncture treatment on a mood scale （Beck Depression Inventory-II, BDI-II）, a simple working memory task （digit span）, and a complex working memory task （letter-number sequencing）; the healthy controls were tested at T1 only. RESULTS： Patients with depression scored worse than the others on the BDI-II, and patients with schizophrenia scored worse than the healthy controls. On the digit span, patients with schizophrenia did not differ from healthy controls whereas they scored worse of all on the letter-number sequencing. With respect to the acupuncture findings, first, the present study showed that the use of acupuncture to treat patients with schizophrenia was both practical and safe. Moreover, acupuncture had a positive effect on the BDI-II for the depression group, but acupuncture had no effect on the digit span and on the letter- number sequencing performance for the two clinical groups. CONCLUSION： The clinical improvement in patients with depression after acupuncture treatment was not accompanied by any significant change in a simple working memory task or in a more complex working memory task; the same was true for the patients with schizophrenia.

Prefrontal cortex and sensory cortices during working memory: quantity and quality

The activity in sensory cortices and the prefrontal cortex （PFC） throughout the delay interval of working memory （WM） tasks reflect two aspects of WM-quality and quantity, respectively. The delay activity in sensory cortices is fine-tuned to sensory information and forms the neural basis of the precision of WM storage, while the delay activity in the PFC appears to represent behavioral goals and filters out irrelevant distractions, forming the neural basis of the quantity of task-relevant information in WM. The PFC and sensory cortices interact through different frequency bands of neuronal oscillation （theta, alpha, and gamma） to fulfill goal-directed behaviors.

A Longitudinal Functional Magnetic Resonance Imaging Study of Working Memory in Patients Following a Transient Ischemic Attack: A Preliminary Study

In this study, we used functional magnetic resonance imaging(fMRI) to investigate longitudinal changes in brain activation during a verbal working memory(VWM) task performed by patients who had experienced a transient ischemic attack(TIA). Twenty-five first-ever TIA patients without visible lesions in conventional MRI and 25 healthy volunteers were enrolled. VWM task-related fMRI was conducted 1 week and 3 months post-TIA. The brain activity evoked by the task and changes over time were assessed. We found that, compared with controls, patients exhibited an increased activation in the bilateral inferior frontal gyrus(IFG), right dorsolateral prefrontal cortex(DLPFC), insula, inferior parietal lobe(IPL), and cerebellum during the task performed 1 week post-TIA. But only the right IFG still exhibited an increased activation at 3 months post-TIA. A direct comparison of fMRI data between 1 week and 3 months post-TIA showed greater activation in the bilateral middle temporal gyrus, right DLPFC, IPL, cerebellum, and left IFG in patients at 1 week post-TIA. We conclude that brain activity patterns induced by a VWM task remain dynamic for a period of time after a TIA, despite the cessation of clinical symptoms. Normalization of the VWM activation pattern may be progressively achieved after transient episodes of ischemia in TIA patients.