Cognitive Deficits In Adults Research Articles

Astrogliosis and compensatory neurogenesis after the first ethanol binge drinking-like exposure in the adolescent rat.

Multiple ethanol binge drinking-like exposures during adolescence in the rat induce neuroinflammation, loss of neurogenesis, and cognitive deficits in adulthood. Interestingly, the first ethanol binge drinking-like exposure during adolescence also induces short- term impairments in cognition and synaptic plasticity in the hippocampus though the cellular mechanisms of these effects are unclear. Here, we sought to determine which of the cellular effects of ethanol might play a role in the disturbances in cognition and synaptic plasticity observed in the adolescent male rat after two binge-like ethanol exposures. Using immunochemistry, we measured neurogenesis, neuronal loss, astrogliosis, neuroinflammation, and synaptogenesis in the hippocampus of adolescent rats 48h after two binge-like ethanol exposures (3g/kg, i.p., 9h apart). We used flow cytometry to analyze activated microglia and identify the TLR4-expressing cell types. We detected increased hippocampal doublecortin immunoreactivity in the subgranular zone (SGZ) of the dentate gyrus (DG), astrogliosis in the SGZ, and a reduced number of mature neurons in the DG and in CA3, suggesting compensatory neurogenesis. Synaptic density decreased in the stratum oriens of CA1 revealing structural plasticity. There was no change in microglial TLR4 expression or in the number of activated microglia, suggesting a lack of neuroinflammatory processes, although neuronal TLR4 was decreased in CA1 and DG. Our findings demonstrate that the cognitive deficits associated with hippocampal synaptic plasticity alterations that we previously characterized 48h after the first binge-like ethanol exposures are associated with hippocampal structural plasticity, astrogliosis, and decreased neuronal TLR4 expression, but not with microglia reactivity.

Effects of a lifestyle intervention on daytime sleepiness and cognitive function

AbstractBackgroundDaytime sleepiness is common in older adults and may result from poor nighttime sleep due to sleep disordered breathing, fragmented sleep, or other sleep disorders. Daytime sleepiness may signify disruption of circadian rhythms and disorder in neural circuitry arising from neurodegenerative disease. We investigated the association between self‐reported daytime sleepiness and cognitive function in Look AHEAD, a randomized clinical trial of an intensive lifestyle intervention (ILI) in a cohort of adults with type 2 diabetes (T2D) and overweight or obesity at baseline.MethodParticipants (aged 45‐76 years) were randomized to ILI or diabetes support and education (DSE) conditions. After ∼10 years, the trial was stopped; observation continued to year 18. We included participants who reported levels of daytime sleepiness at baseline and year 18 (n=2,825). Change in daytime sleepiness was defined as increasing, stayed the same, or decreasing levels of daytime sleepiness. Cognitive assessments at years 13 and 18 included measures of global function, memory, executive function, and attention; a cognitive composite was derived from z‐score averages. The relationship between change in daytime sleepiness from baseline to year 18, and cognitive function at year 18 was examined using analysis of covariance, adjusting for year 13 cognitive performance, baseline age, gender, race/ethnicity, education, APOE ε4 carrier status, baseline CVD history, and baseline daytime sleepiness.ResultParticipants who reported increased daytime sleepiness from baseline to year 18 (n=402), performed significantly worse on the cognitive composite than those who reported no change (n=1089) or decreased levels of daytime sleepiness (n=948), (Least Squares Mean [standard error]) ‐0.50 (0.04); ‐0.40 (0.03), and ‐0.39 (0.03), respectively; p‐value=0.004. Significant interactions between treatment arm and daytime sleepiness were found in executive function (p<0.10) and memory (p<0.001) such that relationships were stronger among ILI compared with DSE participants including poorer scores among those with increasing daytime sleepiness in the executive function (34.3 (0.72); p<0.02); and memory domains (6.5 (0.30); p<0.05).ConclusionIncreasing daytime sleepiness over 18 years predicted poorer cognitive performance in older individuals at high risk for sleep disorders. ILI may exacerbate relationships between increasing daytime sleepiness and cognitive deficits in adults with T2D and overweight/obesity.

The Long-Term Effects of Neonatal Inflammatory Pain on Cognitive Function and Stress Hormones Depend on the Heterogeneity of the Adolescent Period of Development in Male and Female Rats.

Exposure to stress at an early age programs the HPA axis which can lead to cognitive deficits in adults. However, it is not known whether these deficits emerge in adulthood or are expressed earlier in life. The aims of the study were to investigate (1) the immediate effects of early injury-induced stress in one-day-old (P1) and repeated stress on at P1 and P2 rat pups on plasma corticosterone levels; and (2) examine the subsequent long-term effects of this early stress on spatial learning and memory, and stress reactivity in early P26-34 and late P45-53 adolescent male and female rats. Intra-plantar injection of formalin induced prolonged and elevated levels of corticosterone in pups and impaired spatial learning and short- and long-term memory in late adolescent males and long-term memory in early adolescent females. There were sex differences in late adolescence in both learning and short-term memory. Performance on the long-term memory task was better than that on the short-term memory task for all early adolescent male and female control and stressed animals. Short-term memory was better in the late age control rats of both sexes and for formalin treated females as compared with the early age rats. These results are consistent with an impaired function of structures involved in memory (the hippocampus, amygdala, prefrontal cortex) after newborn pain. However, activation of the HPA axis by neonatal pain did not directly correlate with spatial learning and memory outcomes and the consequences of neonatal pain remain are likely multi-determined.

Diabetes, Obesity-Associated Comorbidities and NIH-Toolbox Neurocognitive Performance

Background/Objectives: Severe obesity is associated with cognitive deficits in adults without current or past neurological brain disturbances. This study examined the relationship between specific metabolic and vascular risk factors and cognitive performance on a computerized neurocognitive assessment battery in adults with BMI > 35. Subjects/Methods: 123 adults with Class II or III obesity, ages 20-75, were enrolled in a study of the cognitive and brain effects of reduced BMI and improved diabetes mellitus (DM) following bariatric surgery. Baseline clinical/cognitive assessments were conducted with the NIH Toolbox (NIH-TB) cognitive module prior to surgery, and in severely obese controls recruited from the community. Global, Fluid and Crystallized indices were derived from performance across nine tasks. Hierarchical regression analyses examined six obesity-associated clinical factors (BMI, HbA1c, and DM, hypertension, sleep apnea, and osteoarthritis diagnoses) relative to NIH-TB performance. Results: Fluid Cognition deficits were observed, greatest on attention-executive and cognitive processing speed tasks (Flanker and Pattern Comparison). DM diagnosis was most strongly associated with weaker cognitive performance (Global and Fluid Cognition), and with poorer performance on the Flanker, Pattern Comparison, Picture Sequencing, Verbal Learning, and Symbol Coding tasks. Elevated HbA1c was associated with weaker Card Sorting and Symbol Coding performance, hypertension with poorer Fluid Cognition, and osteoarthritis with lower List Sorting performance. Elevated BMI was only associated with Flanker performance, though DM was more strongly associated with this measure. Conclusion: Deficits of fluid cognitive functions (attention-executive, processing speed) exist among adults with Class II and III obesity. DM was most consistently associated with weaker NIH-TB performance. BMI was not as strongly associated with NIH-TB performance, perhaps reflecting the elevated BMI of the entire sample. That cognitive deficits were linked to specific obesity-associated comorbidities support the validity and potential clinical utility of the NIH-TB for the assessment and management of adults with severe obesity.

Prenatal disruption of D1R-SynGAP complex causes cognitive deficits in adulthood

γ-aminobutyric acid (GABA)-ergic interneurons are essential for the physiological function of the mammalian central nervous system. Dysregulated GABAergic interneuron function has been implicated in the pathophysiology of a number of neurodevelopmental disorders including schizophrenia and autism spectrum disorder. Tangential migration is an important process to ensure the proper localization of GABAergic interneurons. Previously we found that disrupting the interaction between dopamine D1 receptor (D1R) and synaptic Ras GTPase- activating protein (SynGAP) using an interfering peptide (TAT-D1Rpep) during embryonic development impaired tangential migration. Here, we assessed the effects of prenatal disruption of D1R-SynGAP complex with the TAT-D1Rpep on the expression of several behaviours during adulthood. Mice with prenatal D1R-SynGAP disruption exhibited transiently reduced locomotor activity, abnormal sensorimotor gating, impaired sociability and deficits in visual discrimination associative learning compared to their control counterparts. Our findings reinforce the importance of GABAergic interneuron migration in the manifestation of normal motor, sensory, and cognitive behaviours of animals during adulthood.

Effects of adiposity on postural control and cognition in older adults

BackgroundUnderstanding the impacts of increased adiposity on postural control and cognitive deficits in adults is critical for health practitioners in recommending or prescribing effective weight loss regimens. Despite prior work in this area, the knowledge of increased adiposity impacts on postural control and cognitive deficits in older adults (OAs) is still limited. Research questionThe purposes of the current study were: (a) to assess the relationship between postural measures and adiposity measures by using regression model analyses and, (b) to examine the impacts of increased adiposity and age on cognitive performance. MethodsA total of thirty (30) individuals aged 60+ years participated in the study. Participants were classified into three groups based upon their BMI scores at the onset of the study. The normal weight (NW) (BMI: 18.5–24.9 kg/m2), the overweight (OW) (BMI: 25–29.9 kg/m2), and the obese (OB) groups (BMI: 30−40 kg/m2) each had five females and five males. Participants were required to perform two test sessions: (1) anthropometry assessment and body composition scanning; and (2) evaluation of plantar tactile function, postural control, and cognitive function. ResultsOverall, our findings indicate that increased adiposity in OAs is associated with declines in both cognitive function and postural control. SignificanceOur data also indicate that measures such as BMI and abdominal fat mass amounts/ratios offer the best insight to the impact of adiposity on cognitive function and postural control measures. However, further work is still needed to clarify the mechanistic links between adiposity and cognitive-postural deficits.

Early life stress facilitates synapse premature unsilencing to enhance AMPA receptor function in the developing hippocampus.

Chronic early life stress (ELS) increases vulnerability to psychopathologies and cognitive deficits in adulthood by disrupting the function of related neural circuits. However, whether this disruption emerges early in the developing brain remains largely unexplored. In the current study, using an established limited-bedding and nesting model of ELS in postnatal day (P)2-10 mice, we provide direct evidence that ELS caused early modification of hippocampal glutamatergic synapses in the developing brain. We demonstrated that ELS induced rapid enhancement of AMPA receptor function in hippocampal CA1 pyramidal neurons through a postsynaptic mechanism, and importantly, this was associated with premature unsilencing of NMDA receptor-only silent hippocampal synapses. These results suggest that potentiation of AMPAR function may represent an early mediator of ELS-induced alterations of neural networks in the developing brain and may potentially contribute to subsequent cognitive impairments later in life.NEW & NOTEWORTHY Early life stress (ELS) is known to increase the risk of later life cognitive deficits by disrupting neural circuit function. However, whether this disruption emerges early in the developing brain remains largely unexplored. The current study presents direct evidence that ELS prematurely unsilences hippocampal synapses to enhance AMPA receptor functions in a limited-bedding and nesting model, revealing an early mediator of ELS-induced neural circuit reorganizations.

Early 5‐HT6 receptor blockade prevents symptom onset in a model of adolescent cannabis abuse

Cannabis abuse during adolescence confers an increased risk for developing later in life cognitive deficits reminiscent of those observed in schizophrenia, suggesting common pathological mechanisms that remain poorly characterized. In line with previous findings that revealed a role of 5‐HT6 receptor‐operated mTOR activation in cognitive deficits of rodent developmental models of schizophrenia, we show that chronic administration of ∆9‐tetrahydrocannabinol (THC) to mice during adolescence induces a long‐lasting activation of mTOR in prefrontal cortex (PFC), alterations of excitatory/inhibitory balance, intrinsic properties of layer V pyramidal neurons, and long‐term depression, as well as cognitive deficits in adulthood. All are prevented by administrating a 5‐HT6 receptor antagonist or rapamycin, during adolescence. In contrast, they are still present 2 weeks after the same treatments delivered at the adult stage. Collectively, these findings suggest a role of 5‐HT6 receptor‐operated mTOR signaling in abnormalities of cortical network wiring elicited by THC at a critical period of PFC maturation and highlight the potential of 5‐HT6 receptor antagonists as early therapy to prevent cognitive symptom onset in adolescent cannabis abusers.

Neonatal cerebral hypoxia-ischemia in mice triggers age-dependent vascular effects and disabilities in adults; implication of tissue plasminogen activator (tPA)

Neonatal encephalopathy frequently results from hypoxia-ischemia (HI) or inflammation in preterm or term neonates. Neuropathology depends on cerebral development at insult time, but the poor correlation of neuromotor, cognitive, and behavioral disabilities in infancy with initial imaging and clinical records precludes early prognosis. The Rice–Vannucci HI procedure was applied to wild type and tissue plasminogen activator knockout (tPA-KO) mice as surrogates for human preterm (with five-day-old postnatal (P5) mice) or human term (with ten-day-old postnatal (P10) mice). Acute and delayed T2-magnetic resonance imaging (T2-MRI) signals and cognitive deficits in adulthood (spatial memory and social interaction) were investigated in the same animals. Early vascular tPA and matrix metalloproteinase-9 (MMP-9) activities, blood–brain barrier permeability to water or IgG, and microglial activation were assessed separately.HI in P5 or P10 mice induced early hemisphere swelling in T2-MRI scans, and a delayed atrophy of the cortex and hippocampus, but affected white matter in the P5 group only, irrespective of the wild type or tPA-KO genotype. Adults had no motor disabilities, but we did find HI-induced age-dependent deficits, preferentially social interaction and activity in P5 mice, and spatial learning in P10 mice. In P5 mice, tPA-KO prevented MMP-9 activation, IgG extravasation, microglial activation, and behavior impairments. In P10 mice, MMP-9 activation and inflammatory processes remained in the hippocampus of the tPA-KO group, and also contributed to persistent spatial learning deficits.Perinatal HI in mice mimicked the unpredictability of outcomes from imaging in human clinics. Delayed deficits appeared associated to vascular dysfunction-induced inflammation, which recalls our previous work showing major vascular maturation between P5 and P10 stages. Using omics to explore neural, glial, or brain vessel markers in neonate blood may be a promising perspective to identify pertinent prognostic tools.

Developmental neurotoxicity in the context of multiple sevoflurane exposures: Potential role of histone deacetylase 6

Animal studies have demonstrated that multiple exposures to sevoflurane during the postnatal period lead to impaired synaptogenesis and cognitive deficits in adulthood. However, the underlying mechanisms remain unclear. Histone deacetylase 6 (HDAC6), a unique isoform of class II histone deacetylases (HDACs), mediates diverse cellular processes such as cell survival, inflammation, intracellular trafficking and protein degradation. Varieties of literature suggest the importance of HDAC6 in memory formation and abnormal neurodegenerative diseases. The aim of this study was to investigate potential roles of HDAC6 in sevoflurane-induced developmental neurotoxicity. Postnatal day 7 (P7) rat pups were randomly assigned to control group and sevoflurane group (n = 6 for each group). They were exposed to 60% oxygen and 40% nitrogen with or without 3% sevoflurane for 2 h daily for three consecutive days (P7, P8 and P9). Immediately after the last exposure, both hippocampi were harvested for detection of HDAC6 expression and activity. Next, P7 rat pups were divided into control group, sevoflurane group, sevoflurane + Tubastatin A, and Tubastatin A groups (n = 6 for each group in molecular experiments; n = 16 for each group in behavioral testing). A dose of 25 mg/kg body weight of Tubastatin A (a selective HDAC6 inhibitor) were administrated intraperitoneally 30 min prior to each sevoflurane exposure. After treatments, expression levels of synaptophysin and postsynaptic density 95 protein (PSD95) were quantified using Western blot, and synaptic ultrastructure was evaluated by transmission electron microscopy. Additional pups were raised until P49 to measure cognitive performance using the Morris water maze test. Our results demonstrated that multiple sevoflurane exposures enhanced HDAC6 expression and activity in hippocampi of the developing brain. Tubastatin A ameliorated sevoflurane-induced decreases in synaptophysin and PSD95 expression during development, as well as synaptic ultrastructural damage and cognitive deficits in adulthood. In conclusion, HDAC6 is involved in the developmental neurotoxicity caused by multiple sevoflurane exposures and its inhibition may prevent related damage.

17β-Estradiol Treatment Attenuates Neurogenesis Damage and Improves Behavior Performance After Ketamine Exposure in Neonatal Rats.

Ketamine exposure disturbed normal neurogenesis in the developing brain and resulted in subsequent neurocognitive deficits. 17β-estradiol provides robust neuroprotection in a variety of brain injury models in animals of both sexes and attenuates neurodegeneration induced by anesthesia agents. In the present study, we aimed to investigate whether 17β-estradiol could attenuate neonatal ketamine exposure-disturbed neurogenesis and behavioral performance. We treated 7-day-old (Postnatal day 7, PND 7) Sprague-Dawley rats and neural stem cells (NSCs) with either normal saline, ketamine, or 17β-estradiol before/after ketamine exposure, respectively. At PND 14, the rats were decapitated to detect neurogenesis in the subventricular zone (SVZ) and subgranular zone (SGZ) of the hippocampus by immunofluorescence staining. The proliferation, neuronal differentiation, and apoptosis of NSCs were assessed by immunohistochemistry method and TUNEL assay, respectively. The protein levels of cleaved caspase-3 in vivo in addition to GSK-3β and p-GSK-3β in vitro were examined by western blotting. Spatial learning and memory abilities were assessed by Morris water maze (MWM) test at PND 42–47. Ketamine exposure decreased cell proliferation in the SVZ and SGZ, inhibited NSC proliferation and neuronal differentiation, promoted NSC apoptosis and led to adult cognitive deficits. Furthermore, ketamine increased cleaved caspase-3 in vivo and decreased the expression of p-GSK-3β in vitro. Treatment with 17β-estradiol could attenuate ketamine-induced changes both in vivo and in vitro. For the first time we showed that 17β-estradiol alleviated ketamine-induced neurogenesis inhibition and cognitive dysfunction in the developing rat brain. Moreover, the protection of 17β-estradiol was associated with GSK-3β.

Cognitive dysfunction is associated with abnormal responses in cerebral blood flow in patients with single ventricular physiology: Novel insights from transcranial Doppler ultrasound.

Improvements in the management of complex congenital heart disease, including those with single ventricle physiology, have resulted in increased survival. As this population ages, the recognition of cognitive impairment is increasingly important. At present, little is known about the potential mechanisms of cognitive dysfunction. In this cross-sectional study, we aimed to characterize the nature of abnormalities in cerebral blood flow and the relationship to cognitive deficits in adults with single ventricular physiology. Ten adults with single ventricular physiology (age 18-40years) and 12 age- and gender-matched controls underwent transcranial Doppler ultrasound and accompanying cognitive assessment. Patients underwent neuropsychological testing that assessed differing cognitive domains, with subjective cognitive decline determined from a 24-question survey. Transcranial Doppler ultrasound was used to assess baseline cerebral blood flow as well as change in cerebral blood flow velocities from baseline and during cognitive testing. Age, ethnicity, individual, and parental education levels were considered in the multivariate analyses. On assessment of cognitive function, the patient group performed more poorly across each of the measured domains. The control group had a significantly greater increase in cerebral blood flow in response to cognitive stimuli compared to the patient cohort; these differences in response to cognitive stimuli were seen to a similar extent across each of the measured cognitive domains. Adults with Fontan physiology are underperforming in assessments of executive function with associated abnormalities in cerebral perfusion potentially contributing to cognitive deficits.

The Medial Septum Is Insulin Resistant in the AD Presymptomatic Phase: Rescue by Nerve Growth Factor-Driven IRS1 Activation

Basal forebrain cholinergic neurons (BFCN) are key modulators of learning and memory and are high energy-demanding neurons. Impaired neuronal metabolism and reduced insulin signaling, known as insulin resistance, has been reported in the early phase of Alzheimer’s disease (AD), which has been suggested to be “Type 3 Diabetes.” We hypothesized that BFCN may develop insulin resistance and their consequent failure represents one of the earliest event in AD. We found that a condition reminiscent of insulin resistance occurs in the medial septum of 3 months old 3×Tg-AD mice, reported to develop typical AD histopathology and cognitive deficits in adulthood. Further, we obtained insulin resistant BFCN by culturing them with high insulin concentrations. By means of these paradigms, we observed that nerve growth factor (NGF) reduces insulin resistance in vitro and in vivo. NGF activates the insulin receptor substrate 1 (IRS1) and rescues c-Fos expression and glucose metabolism. This effect involves binding of activated IRS1 to the NGF receptor TrkA, and is lost in presence of the specific IRS inhibitor NT157. Overall, our findings indicate that, in a well-established animal model of AD, the medial septum develops insulin resistance several months before it is detectable in the neocortex and hippocampus. Remarkably, NGF counteracts molecular alterations downstream of insulin-resistant receptor and its nasal administration restores insulin signaling in 3×Tg-AD mice by TrkA/IRS1 activation. The cross-talk between NGF and insulin pathways downstream the insulin receptor suggests novel potential therapeutic targets to slow cognitive decline in AD and diabetes-related brain insulin resistance.

Interleukin-6 and Depressive Mood Symptoms: Mediators of the Association Between Childhood Abuse and Cognitive Performance in Middle-Aged Adults.

Childhood abuse is a risk factor for the development of cognitive deficits in adulthood, a relation that is likely mediated by stress-sensitive psychological and physiological indicators. To evaluate whether the link between exposure to childhood abuse and cognitive function in middle adulthood is mediated by interleukin-6 (IL-6), metabolic risk, and depressive mood symptoms. Participants were 770 adults aged 40-65 recruited from the community, who completed the following: (i) a questionnaire assessing exposure to abuse prior to age 18, (ii) a phone interview assessing current depressive mood symptoms, and (iii) a home visit that included blood sampling for evaluation of IL-6 and assessment of metabolic risk indices. A follow-up telephone assessment evaluating cognitive function was completed by 555 of the participants. Structural equation modeling was used to test study hypotheses. Childhood abuse predicted higher levels of IL-6, depressive mood symptoms, and metabolic risk scores (p < .05). The relation between childhood abuse and poorer cognitive performance was mediated by IL-6 (p = .046) and depressive mood symptoms (p = .023), but not metabolic risk. IL-6 and depressive mood symptoms significantly mediated the relation between childhood abuse and adult cognitive function. Exposure to early abuse conveys enduring physiological and psychological effects, which may contribute to cognitive deficits that are evident by middle adulthood. Increased vulnerability for cognitive decline among adults with a history of early trauma and the mediating roles of IL-6 and depressive mood symptoms point to the potential value of interventions that address inflammation or depression, singly or together, to prevent cognitive decline in this at-risk population.

Perinatal hypoxia as a risk factor for psychopathology later in life: the role of dopamine and neurotrophins.

Brain development is influenced by various prenatal, intrapartum, and postnatal events which may interact with genotype to affect the neural and psychophysiological systems related to emotions, specific cognitive functions (e.g., attention, memory), and language abilities and thereby heighten the risk for psychopathology later in life. Fetal hypoxia (intrapartum oxygen deprivation), hypoxia-related obstetric complications, and hypoxia during the early neonatal period are major environmental risk factors shown to be associated with an increased risk for later psychopathology. Experimental models of perinatal hypoxia/ischemia (PHI) showed that fetal hypoxia-a consequence common to many birth complications in humans-results in selective long-term disturbances of the dopaminergic systems that persist in adulthood. On the other hand, neurotrophic signaling is critical for pre- and postnatal brain development due to its impact on the process of neuronal development and its reaction to perinatal stress. The aim of this review is (a) to summarize epidemiological data confirming an association of PHI with an increased risk of a range of psychiatric disorders from childhood through adolescence to adulthood, (b) to present immunohistochemical findings on human autopsy material indicating vulnerability of the dopaminergic neurons of the human neonate to PHI that could predispose infant survivors of PHI to dopamine-related neurological and/or cognitive deficits in adulthood, and

Neurovascular Function and Cognition in Adult Patients With Complex Congenital Heart Disease

Background: Improvements in the management of complex congenital heart disease (CHD), including single ventricle physiology, have resulted in increased survival. As this population ages, the recognition of cognitive impairment is increasingly becoming important. At present, little is known about the nature, mechanism and rate of decline in cognitive function. This cross-sectional study characterised the nature of cognitive deficits in adults with Fontan circulation.

The THINC-Integrated Tool (THINC-it) Screening Assessment for Cognitive Dysfunction: Validation in Patients With Major Depressive Disorder.

To validate the THINC-integrated tool (THINC-it)-a freely available, patient-administered, computerized screening tool integrating subjective and objective measures of cognitive function in adults with major depressive disorder (MDD). Subjects aged 18 to 65 years (n = 100) with recurrent MDD experiencing a major depressive episode of at least moderate severity were evaluated and compared to age-, sex-, and education-matched healthy controls (n = 100). Between January and June 2016, subjects completed the THINC-it, which includes variants of the Choice Reaction Time Identification Task (IDN), One-Back Test, Digit Symbol Substitution Test, Trail Making Test-Part B, and the Perceived Deficits Questionnaire for Depression-5-item (PDQ-5-D). The THINC-it required approximately 10 to 15 minutes for administration and was capable of detecting cognitive deficits in adults with MDD. A total of 44.4% of adults with MDD exhibited cognitive performance at ≥ 1.0 SD below that of healthy controls on standardized mean scores of the THINC-it. Concurrent validity of the overall tool, based on a calculated composite score, was acceptable (r = 0.539, P < .001). Concurrent validity of the component tests ranged from -0.083 (IDN) to 0.929 (PDQ-5-D). Qualitative survey results indicated that there was a high level of satisfaction and perceived value in administering the THINC-it regarding its impact on the appropriateness and quality of care being received. The THINC-it is a valid and sensitive tool for detecting cognitive dysfunction in adults with MDD that is free, easy to use, and rapidly administered. The THINC-it should be incorporated into the assessment and measurement of all patients with MDD, particularly among those with enduring functional impairment. ClinicalTrials.gov identifier: NCT02508493.

Is Obstructive Sleep Apnoea Related to Neuropsychological Function in Healthy Older Adults? A Systematic Review and Meta-Analysis.

Previous systematic reviews and meta-analyses have identified cognitive deficits in adults with obstructive sleep apnoea (OSA). However, quantitative analysis of the association between OSA and neuropsychological performance has not been conducted specifically in older adults, for whom there is a greater risk of cognitive decline. We searched Medline, Embase and PsycINFO through August 2016 for studies describing associations between OSA and neuropsychological outcomes in people aged>50 years. Meta-analyses were performed on these studies for overall cognition and within cognitive domains. Subgroup analyses were performed taking into account risk of bias and moderating differences in study design. 13 studies met eligibility criteria for analysis. A small negative association was found between OSA and all neuropsychological outcomes combined, g=0.18(95% CI 0.04-0.32), and in memory and processing speed domains. Small case-control studies from sleep clinic populations observed the greatest associations, while larger cohort studies from community samples illustrated no association. Analysis accounting for publication bias resulted in a null overall association, g=0.02 (95%CI -0.12 to 0.16). Associations between OSA and cognition in later life are highly variable and the findings differ based on the type and setting of study. It appears some older adults may be at risk of cognitive impairments attributable to OSA; however, the risk of bias renders the evidence inconclusive. High quality research is warranted in clinically diagnosed OSA patients as well as those already experiencing neuropsychological impairment and who may be regarded at higher risk of further cognitive decline.

Effects of Intermittent Alcohol Exposure on Emotion and Cognition: A Potential Role for the Endogenous Cannabinoid System and Neuroinflammation.

Intermittent alcohol exposure is a common pattern of adolescent alcohol use that can lead to binge drinking episodes. Alcohol use is known to modulate the endocannabinoid system (ECS), which is involved in neuronal communication, neuroplasticity, neuroinflammation and behavior. Adolescent male Wistar rats were exposed to 4-week intermittent alcohol intoxication (3 g/kg injections for 4 days/week) or saline (N = 12 per group). After alcohol deprivation, adult rats were assessed for emotionality and cognition and the gene expression of the ECS and other factors related to behavior and neuroinflammation was examined in the brain. Alcohol-exposed rats exhibited anxiogenic-like responses and impaired recognition memory but no motor alterations. There were brain region-dependent changes in the mRNA levels of the ECS and molecular signals compared with control rats. Thus, overall, alcohol-exposed rats expressed higher mRNA levels of endocannabinoid synthetic enzymes (N-acyl-phosphatidylethanolamine phospholipase D and diacylglycerol lipases) in the medial-prefrontal cortex (mPFC) but lower mRNA levels in the amygdala. Furthermore, we observed lower mRNA levels of receptors CB1 CB2 and peroxisome proliferator-activated receptor-α in the striatum. Regarding neuropeptide signaling, alcohol-exposed rats displayed lower mRNA levels of the neuropeptide Y signaling, particularly NPY receptor-2, in the amygdala and hippocampus and higher mRNA levels of corticotropin-releasing factor in the hippocampus. Additionally, we observed changes of several neuroinflammation-related factors. Whereas, the mRNA levels of toll-like receptor-4, tumor necrosis factor-α, cyclooxygenase-2 and glial fibrillary acidic protein were significantly increased in the mPFC, the mRNA levels of cyclooxygenase-2 and glial fibrillary acidic protein were decreased in the striatum and hippocampus. However, nuclear factor-κβ mRNA levels were lower in the mPFC and striatum and allograft inflammatory factor-1 levels were differentially expressed in the amygdala and hippocampus. In conclusion, rats exposed to adolescent intermittent alcohol displayed anxiety-like behavior and cognitive deficits in adulthood and these alterations were accompanied by brain region-dependent changes in the gene expression of the ECS and other signals associated with neuroinflammation and behavior. An intermittent adolescent alcohol exposure has behavioral and molecular consequences in the adult brain, which might be linked to higher vulnerability to addictive behaviors and psychopathologies.

Effects of adolescent methamphetamine and nicotine exposure on behavioral performance and MAP-2 immunoreactivity in the nucleus accumbens of adolescent mice

The neurotoxic effects of methamphetamine (MA) exposure in the developing and adult brain can lead to behavioral alterations and cognitive deficits in adults. Previous increases in the rates of adolescent MA use necessitate that we understand the behavioral and cognitive effects of MA exposure during adolescence on the adolescent brain. Adolescents using MA exhibit high rates of nicotine (NIC) use, but the effects of concurrent MA and NIC in the adolescent brain have not been examined, and it is unknown if NIC mediates any of the effects of MA in the adolescent. In this study, the long-term effects of a neurotoxic dose of MA with or without NIC exposure during early adolescence (postnatal day 30–31) were examined later in adolescence (postnatal day 41–50) in male C57BL/6J mice. Effects on behavioral performance in the open field, Porsolt forced swim test, and conditioned place preference test, and cognitive performance in the novel object recognition test and Morris water maze were assessed. Additionally, the effects of MA and/or NIC on levels of microtubule associated-2 (MAP-2) protein in the nucleus accumbens and plasma corticosterone were examined. MA and NIC exposure during early adolescence separately decreased anxiety-like behavior in the open field test, which was not seen following co-administration of MA/NIC. There was no significant effect of early adolescent MA and/or NIC exposure on the intensity of MAP-2 immunoreactivity in the nucleus accumbens or on plasma corticosterone levels. These results show that early adolescent MA and NIC exposure separately decrease anxiety-like behavior in the open field, and that concurrent MA and NIC exposure does not induce the same behavioral change as either drug alone.