Spatial Working Memory Function Research Articles

Effect of South Sulawesi Propolis in Sevoflurane Anesthesia-Induced Rat Model During Weaning Period: Study Levels of IL-6, TNF⍺, IL-10, and PSD95 in the Prefrontal Cortex

Background: A recent study discovered that exposure to the anesthetic gas sevoflurane in the early years of life can impact cognitive function. Objectives: This study aims to investigate the effects of prolonged and repeated exposure to sevoflurane during the weaning period and whether the administration of propolis, a well-known herbal substance with anti-inflammatory properties, has a beneficial effect on inflammation and synaptic markers in the prefrontal cortex area, as well as its effect on spatial working memory function. Methods: We utilized Sprague Dawley rats aged 21 days (P21), divided into three groups: Control, sevoflurane, and sevoflurane with propolis. The exposure to sevoflurane (3%) was conducted three times for 2 hours each at P21, P23, and P25. Propolis treatments were administered orally for four weeks, starting from the first day of exposure to sevoflurane. Analyses of IL-6, TNF-alpha, and IL-10 levels were performed using ELISA at P25 and P51, while spatial working memory was measured using the spontaneous Y-maze. Results: Exposure to sevoflurane during the weaning period had no effect on IL-6, TNF-alpha, IL-10, and PSD95 levels in the prefrontal cortex, nor on working memory function. Similarly, the administration of propolis did not have any beneficial effect on these parameters. Conclusions: Prolonged and repeated exposure to sevoflurane during the weaning period did not induce neuroinflammation conditions that would affect synaptic markers and working memory function. Further studies are required to identify a dose of sevoflurane that causes detrimental effects on memory function and to explore the beneficial effects of propolis on this condition.

Associations of brain-derived neurotrophic factor rs6265 polymorphism and cognitive function in breast cancer survivors from a cross-sectional study.

Breast cancer survivors (BCS) often complain of cancer-related cognitive impairment (CRCI) during and even months after completing primary cancer treatments, particularly chemotherapy. The etiology of CRCI is unknown, but associations of CRCI with germline genetic polymorphisms have been reported, including Brain-Derived Neurotrophic Factor (BDNF) rs6265 polymorphism. The current study investigated the associations of specific BDNF rs6265 with CRCI. Cancer-related cognitive impairment was assessed using subjective reports of cognitive symptoms (the version 1.0, 8-item short-forms of the Patient-Reported Outcomes Measurement Information System®) and computerized objective cognitive function scores (CANTAB®). BDNF rs6265 genotypes were determined from buccal swabs. The associations of specific BDNF rs6265 with CRCI were examined by either one-way analysis of variance or the Kruskal-Wallis test followed by post hoc tests and rank-based regression analysis. We examined 356 female BCS. The mean (SD) age was 55.6 (9.8) years old, the median (IQR) years since cancer diagnosis were 4.0 (6.0), and 331 (92.7%) were self-described as White. BCS carrying the Met/Met genotype showed poorer results on 'visual episodic memory and new learning' and 'spatial working memory and executive function.' This relationship was observed regardless of prior chemotherapy. Our findings suggest that carrying the BDNF rs6265 Met/Met genotype increases the risk for CRCI in BCS. These results are foundational in nature and provide important information to identify mechanisms underpinning CRCI.

Study on effects of 40 Hz light flicker stimulation on spatial working memory in rats and its neural mechanism

Alzheimer's disease (AD) is a neurodegenerative disease characterized by cognitive impairment, with the predominant clinical diagnosis of spatial working memory (SWM) deficiency, which seriously affects the physical and mental health of patients. However, the current pharmacological therapies have unsatisfactory cure rates and other problems, so non-pharmacological physical therapies have gradually received widespread attention. Recently, a novel treatment using 40 Hz light flicker stimulation (40 Hz-LFS) to rescue the cognitive function of model animals with AD has made initial progress, but the neurophysiological mechanism remains unclear. Therefore, this paper will explore the potential neural mechanisms underlying the modulation of SWM by 40 Hz-LFS based on cross-frequency coupling (CFC). Ten adult Wistar rats were first subjected to acute LFS at frequencies of 20, 40, and 60 Hz. The entrainment effect of LFS with different frequency on neural oscillations in the hippocampus (HPC) and medial prefrontal cortex (mPFC) was analyzed. The results showed that acute 40 Hz-LFS was able to develop strong entrainment and significantly modulate the oscillation power of the low-frequency gamma (lγ) rhythms. The rats were then randomly divided into experimental and control groups of 5 rats each for a long-term 40 Hz-LFS (7 d). Their SWM function was assessed by a T-maze task, and the CFC changes in the HPC-mPFC circuit were analyzed by phase-amplitude coupling (PAC). The results showed that the behavioral performance of the experimental group was improved and the PAC of θ-lγ rhythm was enhanced, and the difference was statistically significant. The results of this paper suggested that the long-term 40 Hz-LFS effectively improved SWM function in rats, which may be attributed to its enhanced communication of different rhythmic oscillations in the relevant neural circuits. It is expected that the study in this paper will build a foundation for further research on the mechanism of 40 Hz-LFS to improve cognitive function and promote its clinical application in the future.

A quasi-comprehensive exploration of the mechanisms of spatial working memory.

Why are some spatial patterns remembered more easily than others? There are many possible mechanisms underlying spatial working memory function. Here, the author explores different mechanisms simultaneously in a single conceptual model. He conducts a large-scale experiment (35.4 million responses used to measure human observers' spatial working memory across 80,000 patterns) and builds a convolutional neural network as a benchmark for what is expected to be explainable. The author then creates a quasi-comprehensive exploration model of spatial working memory based on classic concepts, as well as new notions, including spatial uncertainty, Bayesian integration, out-of-range responses, averaging, grouping, categorical memory, line detection, gap detection, blurring, lateral inhibition, chunking, multiple spatial-frequency channels, redundancy, response bias and random guess. This model provides a tentative overarching framework for the mechanisms of spatial working memory.

Neuroprotective Effect of Yucca schidigera Roezl ex Ortgies Bark Phenolic Fractions, Yuccaol B and Gloriosaol A on Scopolamine-Induced Memory Deficits in Zebrafish.

Y. schidigera contains a number of unusual polyphenols, derivatives of resveratrol and naringenin, called spiro-flavostilbenoids, which have potent in vitro anti-inflammatory, antioxidant, and moderate cholinesterase inhibitory activities. To date, these compounds have not been tested in vivo for the treatment of neurodegenerative diseases. The aim of the present study was to evaluate the effects of both single spiro-flavostilbenoids (yuccaol B and gloriosaol A) and phenolic fractions derived from Y. schidigera bark on scopolamine-induced anxiety and memory process deterioration using a Danio rerio model. Detailed phytochemical analysis of the studied fractions was carried out using different chromatographic techniques and Nuclear Magnetic Resonance (NMR). The novel tank diving test was used as a method to measure zebrafish anxiety, whereas spatial working memory function was assessed in Y-maze. In addition, acetylcholinesterase/butyrylcholinesterase (AChE/BChE) and 15-lipooxygenase (15-LOX) inhibition tests were performed in vitro. All pure compounds and fractions under study exerted anxiolytic and procognitive action. Moreover, strong anti-oxidant capacity was observed, whereas weak inhibition towards cholinesterases was found. Thus, we may conclude that the observed behavioral effects are complex and result rather from inhibition of oxidative stress processes and influence on cholinergic muscarinic receptors (both 15-LOX and scopolamine assays) than effects on cholinesterases. Y. schidigera is a source of substances with desirable properties in the prevention and treatment of neurodegenerative diseases.

Immature Persimmon Suppresses Amyloid Beta (Aβ) Mediated Cognitive Dysfunction via Tau Pathology in ICR Mice.

This study confirmed the ameliorating effect of immature persimmon (Diospyros kaki) ethanolic extract (IPEE) on neuronal cytotoxicity in amyloid beta (Aβ)1–42-induced ICR mice. The administration of IPEE ameliorated the cognitive dysfunction in Aβ1–42-induced mice by improving the spatial working memory, the short-term and long-term memory functions. IPEE protected the cerebral cholinergic system, such as the acetylcholine (ACh) level and acetylcholinesterase (AChE) activity, and antioxidant system, such as the superoxide dismutase (SOD), reduced glutathione (GSH) and malondialdehyde (MDA) contents. In addition, mitochondrial dysfunction against Aβ1–42-induced toxicity was reduced by regulating the reactive oxygen species (ROS), mitochondrial membrane potential and ATP contents. In addition, IPEE regulated the expression levels of tau signaling, such as TNF-α, p-JNK, p-Akt, p-GSK3β, p-tau, p-NF-κB, BAX and caspase 3. Finally, gallic acid, ellagic acid and quercetin 3-O-(6″-acetyl-glucoside) were identified as the physiological compounds of IPEE using ultra-performance liquid chromatography ion mobility separation quadrupole time-of-flight/tandem mass spectrometry (UPLC IMS Q-TOF/MS2).

Lowered serum cesium levels in schizophrenia: association with immune-inflammatory biomarkers and cognitive impairments.

Objectives:A previous study has shown that schizophrenia (SCZ) is accompanied by lowered levels of trace/metal elements, including cesium. However, it is not clear whether changes in cesium, rubidium, and rhenium are associated with activated immune-inflammatory pathways, cognitive impairments, and the symptomatology of SCZ.Methods:This study measured cesium, rubidium, and rhenium, cognitive impairments (using the Brief Assessment of Cognition in Schizophrenia [BACS]), and the levels of cytokines/chemokines interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and eotaxin (CCL11) in 120 patients with SCZ and 54 healthy controls. Severity of illness was assessed using the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS), the Fibromyalgia and Chronic Fatigue Syndrome Rating (FF) Scale, and the Hamilton Depression Rating Scale (HAM-D).Results:Serum cesium was significantly lower in patients with SCZ as compared with controls. Further, serum cesium was significantly and inversely associated with CCL11 and TNF-α, but not IL-1β, in patients with SCZ; significant inverse associations were also noted between serum cesium levels and BPRS, FF, HAM-D, and SANS scores. Finally, cesium was positively correlated with neurocognitive probe results including the Tower of London, Symbol Coding, Controlled Word Association, Category Instances, Digit Sequencing Task, and List Learning tests.Conclusion:The results suggest that lowered serum cesium levels may play a role in the pathophysiology of SCZ, contributing to specific symptom domains including negative, depressive and fatigue symptoms, neurocognitive impairments (spatial working, episodic, and semantic memory and executive functions), and neuroimmune pathways.

Abstract P811: Oral Curcumin Treatment Facilitates Recovery of Function in a Rhesus Monkey Model of Cortical Injury

Curcumin is a primary component of the spice turmeric, and is a potent anti-inflammatory and anti-oxidant compound. In rodent models of brain damage from stroke or trauma, curcumin acts primarily on microglia and astrocytes to inhibit pro-inflammatory signaling pathways and to reduce inflammation and levels of reactive oxygen species (ROS). Further, rats with cortical injury treated with curcumin have smaller lesions and fewer neurological impairments than those treated with vehicle. However, it is not clear whether curcumin exerts the same biological effect in primate brains as in rodent brains, and the effects of curcumin have not yet been extensively tested in monkey models of brain injury. Data from our laboratory has demonstrated that curcumin enhances spatial working memory and motor function in normal aging rhesus monkeys given daily doses of dietary curcumin over two years. The question remains as to whether chronic dietary curcumin can enhance neuroprotection and dampen or ameliorate functional motor deficits after cortical injury. Thus, we administered curcumin to adult, male rhesus monkeys daily for two weeks prior to and 12 weeks following induced cortical injury to the hand-representation of primary motor cortex (M1). Monkeys given daily treatment with oral doses of curcumin, but not those given vehicle, demonstrated significantly enhanced recovery of function in terms of time to retrieve a food reward on our hand dexterity task (HDT). In addition, treated monkeys returned to pre-injury finger-thumb grasp patterns on the HDT, while monkeys that received vehicle developed a compensatory whole hand grasp pattern and never returned to pre-injury grasp. These findings provide evidence that the anti-inflammatory compound, curcumin, is an effective treatment for facilitating recovery of function following cortical injury. Studies investigating the effect of curcumin on the microglia and astrocytes in the brains from these monkeys will provide evidence of the role of curcumin in reducing inflammation and ROS following injury.

Gadolinium Retention in the Central and Peripheral Nervous System: Implications for Pain, Cognition, and Neurogenesis.

Background Despite the wide use of gadolinium-based contrast agents (GBCAs) for enhanced MRI, their neurochemical and behavioral consequences, if any, remain poorly understood. Purpose To investigate the effect of repeated exposure to a linear or macrocyclic GBCA on gadolinium retention in the central and peripheral nervous system of rats and to assess the functional implications of such retention on hippocampal neurogenesis and sensory and cognitive processing. Materials and Methods Seventy male Sprague-Dawley rats (4 weeks old) received intraperitoneal injections of gadoterate meglumine (0.6 or 2.5 mmol per kilogram of body weight), gadodiamide (0.6 or 2.5 mmol/kg), or saline daily for 20 days (February 2018-March 2019). The 5-bromo-2'-deoxyuridine injections were administered every 3 days to determine the number of proliferating cells and the number of newly maturing neurons in the hippocampus. Sensory and cognitive behavioral tests were performed to assess the effect of GBCAs on pain sensitivity and spatial working memory function, respectively. Finally, inductively coupled plasma mass spectrometry analysis was used to quantify gadolinium retention in the brain, spinal cord, and peripheral nerves 24 hours after the last GBCA administration. One-way and mixed-design analyses of variance were used for statistical analysis. Results All GBCAs resulted in significant gadolinium retention in central and peripheral nervous tissues (1.8-333.2 nmol Gd/g tissue). Pain hypersensitivity to thermal and mechanical stimuli (P < .001) was observed after gadodiamide exposure in rats but not after gadoterate meglumine exposure. Rats injected with both GBCAs showed no changes in spatial working memory or in hippocampal cell proliferation and maturation. Conclusion Gadolinium was retained in the spinal cord and peripheral nerves in rats exposed to multiple administrations of linear and macrocyclic contrast agents. Gadodiamide (linear contrast agent) but not gadoterate meglumine (macrocyclic contrast agent) led to pain hypersensitivity, but neither affected spatial working memory performance, hippocampal cellular proliferation, or hippocampal neurogenesis. © RSNA, 2020 See also the editorial by Radbruch in this issue.

ChABC infusions into medial prefrontal cortex, but not posterior parietal cortex, improve the performance of rats tested on a novel, challenging delay in the touchscreen TUNL task.

Perineuronal nets (PNNs) are specialized extracellular matrix structures that surround subsets of neurons throughout the central nervous system (CNS). They are made up of chondroitin sulfate proteoglycans (CSPGs), hyaluronan, tenascin-R, and many other link proteins that together make up their rigid and lattice-like structure. Modulation of PNNs can alter synaptic plasticity and thereby affect learning, memory, and cognition. In the present study, we degraded PNNs in the medial prefrontal (mPFC) and posterior parietal (PPC) cortices of Long–Evans rats using the enzyme chondroitinase ABC (ChABC), which cleaves apart CSPGs. We then measured the consequences of PNN degradation on spatial working memory (WM) with a trial-unique, non-matching-to location (TUNL) automated touchscreen task. All rats were trained with a standard 6 sec delay and 20 sec inter-trial interval (ITI) and then tested under four different conditions: a 6 sec delay, a variable 2 or 6 sec delay, a 2 sec delay with a 1 sec ITI (interference condition), and a 20 sec delay. Rats that received mPFC ChABC treatment initially performed TUNL with higher accuracy, more selection trials completed, and fewer correction trials completed compared to controls in the 20 sec delay condition but did not perform differently from controls in any other condition. Rats that received PPC ChABC treatment did not perform significantly differently from controls in any condition. Posthumous immunohistochemistry confirmed an increase in CSPG degradation products (C4S stain) in the mPFC and PPC following ChABC infusions while WFA staining intensity and parvalbumin positive neuron number were decreased following mPFC, but not PPC, ChABC infusions. These findings suggest that PNNs in the mPFC play a subtle role in spatial WM, but PNNs in the PPC do not. Furthermore, it appears that PNNs in the mPFC are involved in adapting to a challenging novel delay, but that they do not play an essential role in spatial WM function.

Exploring memory function in earthquake trauma survivors with resting-state fMRI and machine learning

BackgroundTraumatized earthquake survivors may develop poor memory function. Resting-state functional magnetic resonance imaging (rs-fMRI) and machine learning techniques may one day aid the clinical assessment of individual psychiatric patients. This study aims to use machine learning with Rs-fMRI from the perspectives of neurophysiology and neuroimaging to explore the association between it and the individual memory function of trauma survivors.MethodsRs-fMRI data was acquired for eighty-nine survivors (male (33%), average age (SD):45.18(6.31) years) of Wenchuan earthquakes in 2008 each of whom was screened by experienced psychiatrists based on the clinician-administered post-traumatic stress disorder (PTSD) scale (CAPS), and their memory function scores were determined by the Wechsler Memory Scale-IV (WMS-IV). We explored which memory function scores were significantly associated with CAPS scores. Using simple multiple kernel learning (MKL), Rs-fMRI was used to predict the memory function scores that were associated with CAPS scores. A support vector machine (SVM) was also used to make classifications in trauma survivors with or without PTSD.ResultsSpatial addition (SA), which is defined by spatial working memory function, was negatively correlated with the total CAPS score (r = − 0.22, P = 0.04). The use of simple MKL allowed quantitative association of SA scores with statistically significant accuracy (correlation = 0.28, P = 0.03; mean squared error = 8.36; P = 0.04). The left middle frontal gyrus and the left precuneus contributed the largest proportion to the simple MKL association frame. The SVM could not make a quantitative classification of diagnosis with statistically significant accuracy.LimitationsThe use of the cross-sectional study design after exposure to an earthquake and the leave-one-out cross-validation (LOOCV) increases the risk of overfitting.ConclusionSpontaneous brain activity of the left middle frontal gyrus and the left precuneus acquired by rs-fMRI may be a brain mechanism of visual working memory that is related to PTSD symptoms. Machine learning may be a useful tool in the identification of brain mechanisms of memory impairment in trauma survivors.

Spatial working memory, not IQ or executive function, discriminates early psychosis and clinically vulnerable creative individuals.

While associations between creativity and psychopathology have been well researched, the specific cognitive processes that distinguish highly creative from those with psychopathology warrant further investigation. This study will examine whether IQ, executive function, cognitive inhibition or spatial working memory differentiate individuals with early psychosis, clinically vulnerable creative individuals, creative controls and non-creative controls. The study sample consisted of 110 participants: early psychosis (n = 21); clinically vulnerable creative controls (n = 25); creative controls (n = 30) and non-creative control (n = 34). The Diagnostic Interview for Psychosis assessed early psychosis participants and the Mini Neuropsychiatric Interview was used to screen for psychopathology in the remaining groups. Several cognitive tests were administered: IQ, neurocognitive measures of executive function and spatial working memory. Creativity was assessed using the Torrance Test of Creativity and Creative Achievement Questionnaire. A measure of vividness of mental imagery was also given. Across all cognitive tests, spatial working memory differentiated the early psychosis group from both creative and non-creative control groups. Spatial working memory predicted group membership but vivid imagery was a better predictor of creative achievement. The early psychosis, clinically vulnerable creative and creative groups all recorded significantly higher results on creative achievement and creative cognition compared to non-creative controls. Our results provide further support for spatial working memory as an early neuro-cognitive marker for early psychosis. Spatial working memory, rather than IQ or executive function, may also be an early protective factor for clinically vulnerable young creative individuals.

Amelioration of cognitive impairments induced by GABA hypofunction in the male rat prefrontal cortex by direct and indirect dopamine D1 agonists SKF-81297 and d-Govadine

Deficits in prefrontal cortex (PFC) GABAergic neurotransmission are linked to cognitive impairments seen in schizophrenia and other disorders, and pharmacological reduction of PFC GABAA transmission disrupts processes including working and spatial memory. This provides an opportunity to examine whether compounds capable of neutralizing GABAergic dysfunction may ameliorate these cognitive deficits. PFC dopamine (DA) D1 receptor activation enhances GABA transmission, raising the possibly that direct or indirect agonists of DA D1 receptors would be effective in reversing working memory and other forms of cognitive deficits. To test this, male rats were pre-treated with two drugs that augment PFC D1 signalling before PFC infusion of the GABAA antagonist, bicuculline (50 ng) and assessment of spatial working and reference memory function. A moderate dose of the full D1 agonist SKF-81297 (0.1 mg/kg) completely reversed PFC GABA hypofunction-induced working memory deficits assessed in an delayed-response task, whereas lower and higher doses (0.05 and 0.3 mg/kg respectively) were associated with mild improvements or deleterious effects. Treatment with the tetrahydroprotoberberine d-govadine (0.5 or 1.0 mg/kg), a synthetic compound known to enhance DA release selectively in the PFC, also significantly improved delayed-response working memory function induced by PFC GABAA antagonism. Furthermore, administration of the optimal dose of both drugs led to a partial rescue of PFC GABA hypofunction-induced reference and short-term spatial memory impairments assessed on a radial maze task. These findings suggest that modulation of PFC DA signalling via actions on the DA D1 receptor represents a promising therapeutic strategy for working memory and other cognitive impairments observed in psychiatric disorders, including those with causes that extend beyond DA dysfunction.

Assessing spatial learning and working memory in plateau zokors in comparison with plateau pikas and laboratory rats

Spatial learning and memory skills are imperative for the survival and fitness of subterranean rodents because of the harsh underground niche in which they live that necessitates the avoidance of higher energy expenditures or probable conflicts with conspecifics or predators. Our study aims to assess the spatial learning and working memory performance of a subterranean rodent species, plateau zokors (Eospalax baileyi), compared to that of the surface-dwelling plateau pikas (Ochotona curzoniae) and laboratory rats (Rattus norvegicus) which spend a considerable time of their lives above ground. Animals were tested with a spatial delayed alternation task in a T-maze for six consecutive days. Plateau zokors showed less efficient learning and working memory capacity in the T-maze compared to plateau pikas and laboratory rats, which maintained accurate and consistent increased spatial learning rates and working memory performances. The three species did not show bias towards a certain arm of the maze. Additionally, clear sex-specific differences were observed in the laboratory rats regarding spatial learning and working memory functions, while in pikas and zokors, no sex-specific variations were detected. The latency to accomplish the task was significantly lower in rats than in pikas and zokors, but no sex-specific differences were detected in all the species. The inferior performance of plateau zokors, compared to pikas and rats, in the T-maze might imply that although the functional significance of working memory may overlap in diverse taxonomic groups, the adaptive value thereof may differ considerably across taxa on account of the divergence in environmental stability, domestication, habitat structure, behavioural needs and the available sensory cues between species.

Neurocognitive and functional outcomes in patients with diffuse frontal lower-grade gliomas undergoing intraoperative awake brain mapping.

Lower-grade gliomas (LGGs) are often observed within eloquent regions, which indicates that tumor resection in these areas carries a potential risk for neurological disturbances, such as motor deficit, language disorder, and/or neurocognitive impairments. Some patients with frontal tumors exhibit severe impairments of neurocognitive function, including working memory and spatial awareness, after tumor removal. The aim of this study was to investigate neurocognitive and functional outcomes of frontal LGGs in both the dominant and nondominant hemispheres after awake brain mapping. Data from 50 consecutive patients with diffuse frontal LGGs in the dominant and nondominant hemispheres who underwent awake brain surgery between December 2012 and September 2018 were retrospectively analyzed. The goal was to map neurocognitive functions such as working memory by using working memory tasks, including digit span testing and N-back tasks. Due to awake language mapping, the frontal aslant tract was frequently identified as a functional boundary in patients with left superior frontal gyrus tumors (76.5%). Furthermore, functional boundaries were identified while evaluating verbal and spatial working memory function by stimulating the dorsolateral prefrontal cortex using the digit span and visual N-back tasks in patients with right superior frontal gyrus tumors (7.1%). Comparing the preoperative and postoperative neuropsychological assessments from the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) and Wechsler Memory Scale-Revised (WMS-R), significant improvement following awake surgery was observed in mean Perceptual Organization (Z = -2.09, p = 0.04) in WAIS-III scores. Postoperative mean WMS-R scores for Visual Memory (Z = -2.12, p = 0.03) and Delayed Recall (Z = -1.98, p = 0.04) were significantly improved compared with preoperative values for every test after awake surgery. No significant deterioration was noted with regard to neurocognitive functions in a comprehensive neuropsychological test battery. In the postoperative course, early transient speech and motor disturbances were observed in 30.0% and 28.0% of patients, respectively. In contrast, late permanent speech and motor disturbances were observed in 0% and 4.0%, respectively. It is noteworthy that no significant postoperative deterioration was identified compared with preoperative status in a comprehensive neuropsychological assessment. The results demonstrated that awake functional mapping enabled favorable neurocognitive and functional outcomes after surgery in patients with diffuse frontal LGGs.

Abnormalities of Motor Imagery Ability Associated with Spatial Working Memory Dysfunction in Chronic Schizophrenic Patients

Background: Spatial working memory (SWM) and mental imagery involve the processes of encoding, maintaining, and transforming spatial information. Patients with schizophrenia show impairments in both SWM and mental imagery. Yet, there is scarce evidence on the relationship between impairment in the two cognitive functions in the patients. Objectives: The goal of the present study was to investigate motor imagery ability and SWM function and their relationship in schizophrenic patients. Methods: The present case-control study compared the performance of 18 schizophrenic patients and 18 normal persons. The motor imagery was evaluated with the mental hand rotation task (HRT) and SWM was examined with the Dot test of visuospatial working memory (VSWM) across the three delays. Results: The comparison of HRT results between the patients and the controls showed a slower and less accurate performance of the patients. On the Dot test of VSWM, performance was significantly less accurate at the three delays in schizophrenic patients relative to the controls. Moreover, there was a negative significant correlation between mental rotation accuracy and distance inaccuracy across the three delays in schizophrenic patients. Conclusions: These results provide further evidence that impaired passive maintenance of internal representation might be the underlying mechanism of motor imagery dysfunction in patients with schizophrenia.

The Association Between Negative Attributional Style and Working Memory Performance

Introduction:It has been proposed that negative attributions contribute to impairment in cognitive task processing. However, it is still unknown whether negative attributions influence task processing in all cognitive tasks.Methods:To investigate this, 91 healthy participants completed attributional style questionnaire and performed three Working Memory (WM) tasks, which associated with different functions of WM (i.e. Central Executive System (CES) and visuospatial sketchpad).Results:The results demonstrated that negative attributions contribute to the impairment in cognitive tasks which is associated with spatial working memory rather than main central executive functions (i.e. switching and inhibition).Conclusions:It is concluded that negative attributions may selectively disrupt spatial working memory functions, thus a detrimental effect of negative attributions may be task specific.

Long-term effects of curcumin in the non-human primate brain

Curcumin has recently been shown to be a potential treatment for slowing or ameloriating cognitive decline during aging in our nonhuman primate model of normal aging. In these same monkeys, we studied for the first time the neurological impacts of long-term curcumin treatments using longitudinal magnetic resonance imaging (MRI). Sixteen rhesus monkeys received curcumin or a vehicle control for 14–18 months. We applied a combination of structural and diffusion MRI to determine whether the curcumin resulted in structural or functional changes in focal regions of the brain. The longitudinal imaging revealed decreased microscale diffusivity (mD) measurements mainly in the hippocampus and basal forebrain structures of curcumin treated animals. Changes in generalized fractional anisotropy (GFA) and grey matter density (GMd) measurements indicated an increased grey matter density in cortical ROIs with improved white matter integrity in limbic, cerebellar, and brain stem regions. These findings suggest that noticeable changes in the neuronal environment could be induced from long-term curcumin treatments. Results may provide a neurological basis on the recent findings demonstrating improved spatial working memory and motor function in nonhuman primates.

The relationship between spatial working memory precision and attention and inhibitory control in young children

Spatial working memory (SWM) and executive functions, including attention, inhibition and working memory, are important for children’s well-being, educational attainment, and social relationships (Bull & Scerif, 2001; Posner, 2012; Riggs, Jahromi, Razza, Dillworth-Bart, & Mueller, 2006). The purpose of the current study is to examine the relationship between attention and inhibition, and a SWM task in 4–8-year-old children. The SWM task measured children’s ability to remember the location of a target on a blank screen both with and without a distractor present during the delay. We conducted a secondary data analysis of this task from two previous studies (Beattie, 2014; Schutte, Torquati, & Beattie, 2017). Multilevel models showed that for younger children, faster reaction time on an attention task was related to errors in the SWM task that were more similar to older children. In addition, children whose parents indicated they had higher inhibitory control inhibited distractors more than other children. Overall, the findings demonstrate that children with greater attention and inhibition abilities also had greater SWM abilities.

Inactivation of nucleus reuniens impairs spatial working memory and behavioral flexibility in the rat.

The hippocampal formation (HF) and medial prefrontal cortex (mPFC) play critical roles in spatial working memory (SWM). The nucleus reuniens (RE) of the ventral midline thalamus is an important anatomical link between the HF and mPFC, and as such is crucially involved in SWM functions that recruit both structures. Little is known, however, regarding the role of RE in other behaviors mediated by this circuit. In the present study, we examined the role of RE in spatial working memory and executive functioning following reversible inactivation of RE with either muscimol or procaine. Rats were implanted with an indwelling cannula targeting RE and trained in a delayed nonmatch to sample spatial alternation T-maze task. For the task, sample and choice runs were separated by moderate or long delays (30, 60, and 120 s). Following asymptotic performance, rats were tested following infusions of drug or vehicle. Muscimol infused into RE impaired SWM at all delays, whereby procaine only impaired performance at the longest delays. Furthermore, RE inactivation with muscimol produced a failure in win-shift strategy as well as severe spatial perseveration, whereby rats persistently made re-entries into incorrect arms during correction trials, despite the absence of reward. This demonstrated marked changes in behavioral flexibility and response strategy. These results strengthen the role of nucleus reuniens as a pivotal link between hippocampus and prefrontal cortex in cognitive and executive functions and suggest that nucleus reuniens may be a potential target in the treatment of CNS disorders such as schizophrenia, attention deficit hyperactivity disorder, addiction, and obsessive-compulsive disorder, whose symptoms are defined by hippocampal-prefrontal dysfunctions.