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1.
Curr HIV/AIDS Rep ; 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38602558

ABSTRACT

PURPOSE OF REVIEW: Cannabis may have beneficial anti-inflammatory effects in people with HIV (PWH); however, given this population's high burden of persisting neurocognitive impairment (NCI), clinicians are concerned they may be particularly vulnerable to the deleterious effects of cannabis on cognition. Here, we present a systematic scoping review of clinical and preclinical studies evaluating the effects of cannabinoid exposure on cognition in HIV. RECENT FINDINGS: Results revealed little evidence to support a harmful impact of cannabis use on cognition in HIV, with few eligible preclinical data existing. Furthermore, the beneficial/harmful effects of cannabis use observed on cognition were function-dependent and confounded by several factors (e.g., age, frequency of use). Results are discussed alongside potential mechanisms of cannabis effects on cognition in HIV (e.g., anti-inflammatory), and considerations are outlined for screening PWH that may benefit from cannabis interventions. We further highlight the value of accelerating research discoveries in this area by utilizing translatable cross-species tasks to facilitate comparisons across human and animal work.

3.
Neuropharmacology ; 248: 109851, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38325772

ABSTRACT

Heightened risk-based decision-making is observed across several neuropsychiatric disorders including schizophrenia, bipolar disorder, and Parkinson's disease, yet no treatments exist that effectively normalize this aberrant behavior. Preclinical risk-based decision-making paradigms have identified the important modulatory roles of dopamine and sex in the performance of such tasks, though specific task parameters may alter such effects (e.g., punishment and reward values). Previous work has highlighted the role of dopamine 2-like receptors (D2R) during performance of the Risk Preference Task (RPT) in male rats, however sex was not considered as a factor in this study, nor were treatments identified that reduced risk preference. Here, we utilized the RPT to determine sex-dependent differences in baseline performance and impact of the D2R receptor agonist pramipexole (PPX), and antagonist sulpiride (SUL) on behavioral performance. Female rats exhibited heightened risk-preference during baseline testing. Consistent with human studies, PPX increased risk-preference across sex, though the effects of PPX were more pronounced in female animals. Importantly, SUL reduced risk-preference in these rats across sexes. Thus, under the task specifications of the RPT that does not include punishment, female rats were more risk-preferring and required higher PPX doses to promote risky choices compared to males. Furthermore, blockade of D2R receptors may reduce risk-preference of rats, though further studies are required.


Subject(s)
Dopamine , Sex Characteristics , Humans , Rats , Female , Male , Animals , Dopamine/pharmacology , Dopamine Agonists/pharmacology , Pramipexole/pharmacology , Receptors, Dopamine , Decision Making , Reward
4.
Mol Psychiatry ; 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38351173

ABSTRACT

Alternatives to traditional categorical diagnoses have been proposed to improve the validity and utility of psychiatric nosology. This paper continues the companion review of an alternative model, the psychosis superspectrum of the Hierarchical Taxonomy of Psychopathology (HiTOP). The superspectrum model aims to describe psychosis-related psychopathology according to data on distributions and associations among signs and symptoms. The superspectrum includes psychoticism and detachment spectra as well as narrow subdimensions within them. Auxiliary domains of cognitive deficit and functional impairment complete the psychopathology profile. The current paper reviews evidence on this model from neurobiology, treatment response, clinical utility, and measure development. Neurobiology research suggests that psychopathology included in the superspectrum shows similar patterns of neural alterations. Treatment response often mirrors the hierarchy of the superspectrum with some treatments being efficacious for psychoticism, others for detachment, and others for a specific subdimension. Compared to traditional diagnostic systems, the quantitative nosology shows an approximately 2-fold increase in reliability, explanatory power, and prognostic accuracy. Clinicians consistently report that the quantitative nosology has more utility than traditional diagnoses, but studies of patients with frank psychosis are currently lacking. Validated measures are available to implement the superspectrum model in practice. The dimensional conceptualization of psychosis-related psychopathology has implications for research, clinical practice, and public health programs. For example, it encourages use of the cohort study design (rather than case-control), transdiagnostic treatment strategies, and selective prevention based on subclinical symptoms. These approaches are already used in the field, and the superspectrum provides further impetus and guidance for their implementation. Existing knowledge on this model is substantial, but significant gaps remain. We identify outstanding questions and propose testable hypotheses to guide further research. Overall, we predict that the more informative, reliable, and valid characterization of psychopathology offered by the superspectrum model will facilitate progress in research and clinical care.

5.
Cogn Affect Behav Neurosci ; 24(2): 269-278, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38168850

ABSTRACT

Translation of drug targets from preclinical studies to clinical trials has been aided by cross-species behavioral tasks, but evidence for brain-based engagement during task performance is still required. Cross-species progressive ratio breakpoint tasks (PRBTs) measure motivation-related behavior and are pharmacologically and clinically sensitive. We recently advanced elevated parietal alpha power as a cross-species electroencephalographic (EEG) biomarker of PRBT engagement. Given that amphetamine increases breakpoint in mice, we tested its effects on breakpoint and parietal alpha power in both humans and mice. Twenty-three healthy participants performed the PRBT with EEG after amphetamine or placebo in a double-blind design. C57BL/6J mice were trained on PRBT with EEG (n = 24) and were treated with amphetamine or vehicle. A second cohort of mice was trained on PRBT without EEG (n = 40) and was treated with amphetamine or vehicle. In humans, amphetamine increased breakpoint. In mice, during concomitant EEG, 1 mg/kg of amphetamine significantly decreased breakpoint. In cohort 2, however, 0.3 mg/kg of amphetamine increased breakpoint consistent with human findings. Increased alpha power was observed in both species as they reached breakpoint, replicating previous findings. Amphetamine did not affect alpha power in either species. Amphetamine increased effort in humans and mice. Consistent with previous reports, elevated parietal alpha power was observed in humans and mice as they performed the PRBT. Amphetamine did not affect this EEG biomarker of effort. Hence, these findings support the pharmacological predictive validity of the PRBT to measure effort in humans and mice and suggest that this EEG biomarker is not directly reflective of amphetamine-induced changes in effort.


Subject(s)
Amphetamine , Central Nervous System Stimulants , Electroencephalography , Mice, Inbred C57BL , Motivation , Amphetamine/pharmacology , Humans , Animals , Male , Electroencephalography/drug effects , Adult , Young Adult , Double-Blind Method , Motivation/drug effects , Motivation/physiology , Female , Central Nervous System Stimulants/pharmacology , Central Nervous System Stimulants/administration & dosage , Mice , Alpha Rhythm/drug effects , Alpha Rhythm/physiology
6.
Accid Anal Prev ; 198: 107397, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38271896

ABSTRACT

Novice drivers are at a greatly inflated risk of crashing. This led in the 20th century to numerous attempts to develop training programs that could reduce their crash risk. Yet, none proved effective. Novice drivers were largely considered careless, not clueless. This article is a case study in the United States of how a better understanding of the causes of novice driver crashes led to training countermeasures targeting teen driving behaviors with known associations with crashes. These effects on behaviors were large enough and long-lasting enough to convince insurance companies to develop training programs that they offered around the country to teen drivers. The success of the training programs at reducing the frequency of behaviors linked to crashes also led to several large-scale evaluations of the effect of the training programs on actual crashes. A reduction in crashes was observed. The cumulative effect has now led to state driver licensing agencies considering as a matter of policy both to include items testing the behaviors linked to crashes on licensing exams and to require training on safety critical behaviors. The effort has been ongoing for over a quarter century and is continuing. The case study highlights the critical elements that made it possible to move from a paradigm shift in the understanding of crash causes to the development and evaluation of crash countermeasures, to the implementation of those crash countermeasures, and to subsequent policy changes at the state and federal level. Key among these elements is the development of simple, scalable solutions.


Subject(s)
Accidents, Traffic , Automobile Driving , Adolescent , Humans , United States , Accidents, Traffic/prevention & control , Licensure , Policy , Causality
7.
Behav Sleep Med ; 22(2): 217-233, 2024 Mar 03.
Article in English | MEDLINE | ID: mdl-37401160

ABSTRACT

OBJECTIVES: Both sleep and cognition are partially modulated by the endocannabinoid (ECB) system. Cannabis has been reported to have effects on sleep and cognition. This review aims to summarize the recent literature on the ECB system, the role of cannabis and the ECB system on sleep regulation and cognition. Further, this review will identify existing gaps in knowledge and suggest potential targets for future research. METHODS: We performed this review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Reports were identified by searching PubMed/MEDLINE, Embase, CINAHL, Web of Science, and PsycINFO for articles published through September 2021 for studies with data available on aspects of cognition, cannabis, or the ECB system, and sleep or circadian rhythms (CRs). RESULTS: We identified 6 human and 6 animal studies to be eligible for inclusion in this review. Several human studies found that cannabis use is not associated with changes in sleep quality or cognitive function. However, individual cannabinoids appeared to have independent effects on cognition and sleep; THC alone decreased cognitive performance and increased daytime sleepiness, whereas CBD alone had no effect on sleep or cognition. Animal studies demonstrated that manipulation of the ECB system altered activity and cognitive function, some of which appeared to be dependent on the light/dark cycle. CONCLUSION: The sleep-wake cycle and CRs are both likely modulated by the ECB system, potentially resulting in effects on cognition, however this area is critically understudied.


Subject(s)
Cannabinoids , Cannabis , Animals , Humans , Endocannabinoids , Sleep , Cognition
9.
Arch Womens Ment Health ; 26(6): 863-868, 2023 12.
Article in English | MEDLINE | ID: mdl-37667089

ABSTRACT

We examined the role of menopausal status in daily mood and cognitive performance among women with bipolar disorder (BD) compared to healthy comparison women. We analyzed the association of menopausal status, bipolar diagnosis, and their interaction on daily mood assessed by mobile surveys and attentional performance measured multiple times over 2 weeks. Menopausal status was associated with more daily negative affect in women with BD, but not related to attentional performance.


Subject(s)
Bipolar Disorder , Humans , Female , Bipolar Disorder/psychology , Affect , Menopause/psychology , Cognition
10.
Genetics ; 225(2)2023 10 04.
Article in English | MEDLINE | ID: mdl-37595066

ABSTRACT

Behavioral persistency reflects internal brain states, which are the foundations of multiple brain functions. However, experimental paradigms enabling genetic analyses of behavioral persistency and its associated brain functions have been limited. Here, we report novel persistent behavioral responses caused by electric stimuli in the nematode Caenorhabditis elegans. When the animals on bacterial food are stimulated by alternating current, their movement speed suddenly increases 2- to 3-fold, persisting for more than 1 minute even after a 5-second stimulation. Genetic analyses reveal that voltage-gated channels in the neurons are required for the response, possibly as the sensors, and neuropeptide signaling regulates the duration of the persistent response. Additional behavioral analyses implicate that the animal's response to electric shock is scalable and has a negative valence. These properties, along with persistence, have been recently regarded as essential features of emotion, suggesting that C. elegans response to electric shock may reflect a form of emotion, akin to fear.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/genetics , Neurons , Movement , Signal Transduction/physiology
11.
Acta Anaesthesiol Scand ; 67(10): 1294-1305, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37403236

ABSTRACT

Traditional risk factors used for predicting poor postoperative recovery have focused on postoperative complications, adverse symptoms (nausea, pain), length of hospital stay, and patient quality of life. Despite these being traditional performance indicators of patient postoperative "status," they may not fully define the multidimensional nature of patient recovery. The definition of postoperative recovery is thus evolving to include patient-reported outcomes that are important to the patient. Previous reviews have focused on risk factors for the above traditional outcomes after major surgery. Yet, there remains a need for further study of risk factors predicting multidimensional patient-focused recovery, and investigation beyond the immediate postoperative period after patients are discharged from the hospital. This review aimed to appraise the current literature identifying risk factors for multidimensional patient recovery. METHODS: A systematic review without meta-analysis was performed to qualitatively summarize preoperative risk factors for multidimensional recovery 4-6 weeks after major surgery (PROSPERO, CRD42022321626). We reviewed three electronic databases between January 2012 and April 2022. The primary outcome was risk factors for multidimensional recovery at 4-6 weeks. A GRADE quality appraisal and a risk of bias assessment were completed. RESULTS: In total, 5150 studies were identified, after which 1506 duplicates were removed. After the primary and secondary screening, nine articles were included in the final review. Interrater agreements between the two assessors for the primary and secondary screening process were 86% (k = 0.47) and 94% (k = 0.70), respectively. Factors associated with poor recovery were found to include ASA grade, recovery tool baseline score, physical function, number of co-morbidities, previous surgery, and psychological well-being. Mixed results were reported for age, BMI, and preoperative pain. Due to the observational nature, heterogeneity, multiple definitions of recovery, and moderate risk of bias of the primary studies, the quality of evidence was rated from very low to low. CONCLUSION: Our review found that there were few studies assessing preoperative risk factors as predictors for poor postoperative multidimensional recovery. This confirms the need for higher quality studies assessing risk for poor recovery, ideally with a consistent and multi-dimensional definition of recovery.

12.
Transl Psychiatry ; 13(1): 167, 2023 05 12.
Article in English | MEDLINE | ID: mdl-37173343

ABSTRACT

Impulsivity is a multidimensional heritable phenotype that broadly refers to the tendency to act prematurely and is associated with multiple forms of psychopathology, including substance use disorders. We performed genome-wide association studies (GWAS) of eight impulsive personality traits from the Barratt Impulsiveness Scale and the short UPPS-P Impulsive Personality Scale (N = 123,509-133,517 23andMe research participants of European ancestry), and a measure of Drug Experimentation (N = 130,684). Because these GWAS implicated the gene CADM2, we next performed single-SNP phenome-wide studies (PheWAS) of several of the implicated variants in CADM2 in a multi-ancestral 23andMe cohort (N = 3,229,317, European; N = 579,623, Latin American; N = 199,663, African American). Finally, we produced Cadm2 mutant mice and used them to perform a Mouse-PheWAS ("MouseWAS") by testing them with a battery of relevant behavioral tasks. In humans, impulsive personality traits showed modest chip-heritability (~6-11%), and moderate genetic correlations (rg = 0.20-0.50) with other personality traits, and various psychiatric and medical traits. We identified significant associations proximal to genes such as TCF4 and PTPRF, and also identified nominal associations proximal to DRD2 and CRHR1. PheWAS for CADM2 variants identified associations with 378 traits in European participants, and 47 traits in Latin American participants, replicating associations with risky behaviors, cognition and BMI, and revealing novel associations including allergies, anxiety, irritable bowel syndrome, and migraine. Our MouseWAS recapitulated some of the associations found in humans, including impulsivity, cognition, and BMI. Our results further delineate the role of CADM2 in impulsivity and numerous other psychiatric and somatic traits across ancestries and species.


Subject(s)
Genome-Wide Association Study , Substance-Related Disorders , Humans , Animals , Mice , Phenotype , Impulsive Behavior , Personality/genetics , Polymorphism, Single Nucleotide , Cell Adhesion Molecules/genetics
13.
Neuropharmacology ; 236: 109599, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37217074

ABSTRACT

Although it is well established that alcohol consumption during pregnancy can lead to lifelong difficulties in offspring, Fetal Alcohol Spectrum Disorders (FASD) remain a common neurodevelopmental syndrome. Translational behavioral tools that target similar brain circuits across species can facilitate understanding of these cognitive consequences. Touchscreen behavioral tasks for rodents enable easy integration of dura recordings of electroencephalographic (EEG) activity in awake behaving animals, with clear translational generalizability. Recently, we showed that Prenatal Alcohol Exposure (PAE) impairs cognitive control on the touchscreen 5-Choice Continuous Performance Task (5C-CPT) which requires animals to touch on target trials (hit) and withhold responding on non-target trials (correct rejection). Here, we extended these findings to determine whether dura EEG recordings would detect task-relevant differences in medial prefrontal cortex (mPFC) and posterior parietal cortex (PPC) corresponding with behavioral alterations in PAE animals. Replicating previous findings, PAE mice made more false alarm responses versus controls and had a significantly lower sensitivity index. All mice, regardless of sex or treatment, demonstrated increased frontal theta-band power during correct trials that followed an error (similar to post-error monitoring commonly seen in human participants). All mice showed a significant decrease in parietal beta-band power when performing a correct rejection versus a hit. PAE mice of both sexes showed a significantly larger decrease in parietal beta-band power when successfully rejecting non-target stimuli. These findings suggest that moderate exposure to alcohol during development can have long lasting effects on cognitive control, and task-relevant neural signals may provide a biomarker of impaired function across species.


Subject(s)
Fetal Alcohol Spectrum Disorders , Prenatal Exposure Delayed Effects , Male , Humans , Female , Mice , Animals , Pregnancy , Rodentia , Prenatal Exposure Delayed Effects/psychology , Ethanol/toxicity , Cognition , Electroencephalography , Neuropsychological Tests
14.
Neurosci Biobehav Rev ; 148: 105119, 2023 05.
Article in English | MEDLINE | ID: mdl-36889561

ABSTRACT

The past 30 years of IBNS has included research attempting to treat the cognitive and behavioral deficits observed in people with psychiatric conditions. Early work utilized drugs identified from tests thought to be cognition-relevant, however the high failure rate crossing the translational-species barrier led to focus on developing valid cross-species translational tests. The face, predictive, and neurobiological validities used to assess animal models of psychiatry can be used to validate these tests. Clinical sensitivity is another important aspect however, for if the clinical population targeted for treatment does not exhibit task deficits, then why develop treatments? This review covers some work validating cross-species translational tests and suggests future directions. Also covered is the contribution IBNS made to fostering such research and my role in IBNS, making it more available to all including fostering mentor/mentee programs plus spearheading diversity and inclusivity initiatives. All science needs support and IBNS has supported research recreating the behavioral abnormalities that define psychiatric conditions with the aim to improve the lives of people with such conditions.


Subject(s)
Mental Disorders , Animals , Mental Disorders/therapy , Cognition , Disease Models, Animal , Neurobiology
15.
Neuropsychopharmacology ; 48(6): 852-856, 2023 05.
Article in English | MEDLINE | ID: mdl-36928352

ABSTRACT

Research regarding the mental health of the Lesbian, Gay, Bisexual, Transgender, Queer, Intersex, Asexual, 2 Spirit (LGBTQIA2S+) community has been historically biased by individual and structural homophobia, biphobia, and transphobia, resulting in research that does not represent the best quality science. Furthermore, much of this research does not serve the best interests or priorities of LGBTQIA2S + communities, despite significant mental health disparities and great need for quality mental health research and treatments in these populations. Here, we will highlight how bias has resulted in missed opportunities for advancing understanding of mental health within LGBTQIA2S + communities. We cite up-to-date research on mental health disparities facing the LGBTQIA2S + community and targeted treatment strategies, as well as guidance from health care professionals. Importantly, research is discussed from both preclinical and clinical perspectives, providing common language and research priorities from a translational perspective. Given the rising tide of anti-transgender sentiment among certain political factions, we further emphasize and discuss the impact of historical and present day ciscentrism and structural transphobia in transgender mental health research, from both clinical and translational perspectives, with suggestions for future directions to improve the quality of this field. Finally, we address current best practices for treatment of mental health issues in this community. This approach provides an opportunity to dispel myths regarding the LGBTQIA2S + community as well as inform the scientific community of best practices to work with this community in an equitable manner. Thus, our approach ties preclinical and clinical research within the LGBTQIA2S + community.


Subject(s)
Sexual and Gender Minorities , Transgender Persons , Transsexualism , Female , Humans , Transgender Persons/psychology , Sexual Behavior , Gender Identity
16.
AIDS Behav ; 27(8): 2617-2628, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36738342

ABSTRACT

Deficits in social cognition are seen in both people living with HIV (PWH) and people with a history of methamphetamine (METH) dependence. Dually affected individuals may experience additive negative effects on social cognition due to these conditions. We evaluated social cognition in 4 diagnostic groups (HIV-/METH-, HIV-/METH+, HIV+/METH-, HIV+/METH+). First, we used traditional social-emotional functioning assessments, the Difficulties in Emotion Regulation Scale and the Faux Pas Task, to determine any significant effects of METH dependence and HIV on social cognition. Next, we quantified social cognition using the Human Behavioral Pattern Monitor by evaluating social behavior represented by interaction with novel objects. METH dependence significantly affected social-emotional functions and HIV significantly affected on object interactions, however no significant additive effects were observed using these methods. The nuanced relationship between HIV and METH dependence suggests that other factors (i.e., adaptive life skills) likely mediate social cognition-related behaviors.


RESUMEN: Los déficits en la cognición social se observan tanto en las personas que viven con el VIH (PWH) como en las personas con antecedentes de dependencia de la metanfetamina (METH). Las personas con ambas condiciones pueden experimentar efectos negativos aditivos en la cognición social. Evaluamos la cognición social en 4 grupos de diagnóstico (VIH−/METH−, VIH−/METH+, VIH+/METH−, VIH+/METH+). En primer lugar, utilizamos evaluaciones tradicionales del funcionamiento socioemocional, la Escala de Dificultades en la Regulación Emocional y la Prueba de Faux Pas, para determinar efecto significativo debido a la dependencia de METH y el VIH en la cognición social. Entonces, cuantificamos la cognición social utilizando el Monitor de Patrones de comportamiento humano mediante la evaluación del comportamiento social representado por la interacción con objetos novedosos. La dependencia de METH afectó significativamente las funciones socioemocionales y el VIH afectó significativamente las interacciones con los objetos, sin embargo, no se observaron efectos aditivos significativos al usar estos métodos. La relación compleja entre el VIH y la dependencia de METH sugiere que otros factores (i.e., habilidades adaptativas) probablemente regulan los comportamientos relacionados con la cognición social.


Subject(s)
Amphetamine-Related Disorders , Central Nervous System Stimulants , Cognition Disorders , HIV Infections , Methamphetamine , Humans , HIV Infections/psychology , Amphetamine-Related Disorders/complications , Amphetamine-Related Disorders/psychology , Methamphetamine/adverse effects , Cognition , Cognition Disorders/psychology , Central Nervous System Stimulants/pharmacology
17.
Psychopharmacology (Berl) ; 240(11): 2303-2315, 2023 Nov.
Article in English | MEDLINE | ID: mdl-36806900

ABSTRACT

RATIONALE: Seasonal birth patterns consistently implicate winter gestation as a risk factor for several psychiatric conditions. We recently demonstrated that short-active (SA; 19:5 light:dark)-i.e., "winter-like"-photoperiod exposure across gestation and early life (E0-P28) induces psychiatrically relevant behavioral abnormalities in adult mice, including reduced immobility in the forced swim test (FST) and effortful amotivation. It is unknown, however, whether these effects were driven primarily by prenatal or postnatal mechanisms, and whether perinatal SA photoperiod would similarly reduce effort expenditure in a task relevant to everyday decision-making. OBJECTIVES AND METHODS: We first tested male and female mice exposed to either gestational (E0-P0) or postnatal (E0-P28) SA photoperiod in the FST to determine whether the previously observed alteration was driven primarily by prenatal versus postnatal photoperiod. We then assessed whether SA gestational photoperiod reduces effortful choice behavior in the cross-species effort-based decision-making task (EBDMT) and whether any such deficit could be remediated by d-amphetamine (0.1 and 0.3 mg/kg, i.p.). RESULTS: Mice exposed to prenatal, but not postnatal, SA photoperiod exhibited reduced FST immobility relative to controls and also demonstrated condition-dependently reduced preference for high-effort/high-reward versus low-effort/low-reward contingencies in the EBDMT. This effortful choice deficit was normalized by 0.1 mg/kg amphetamine. CONCLUSIONS: These data: (1) suggest a greater contribution of gestational versus postnatal light conditions to the behavioral effects of perinatal SA photoperiod; and (2) implicate altered dopamine signaling in the behavioral phenotype of the SA-born mouse and possibly in the etiology of winter gestation-associated cases of psychiatric disease.

18.
Neuropsychopharmacology ; 48(9): 1377-1385, 2023 08.
Article in English | MEDLINE | ID: mdl-36509858

ABSTRACT

The ability to appropriately update the value of a given action is a critical component of flexible decision making. Several psychiatric disorders, including schizophrenia, are associated with impairments in flexible decision making that can be evaluated using the probabilistic reversal learning (PRL) task. The PRL task has been reverse-translated for use in rodents. Disrupting glutamate neurotransmission during early postnatal neurodevelopment in rodents has induced behavioral, cognitive, and neuropathophysiological abnormalities relevant to schizophrenia. Here, we tested the hypothesis that using the NMDA receptor antagonist phencyclidine (PCP) to disrupt postnatal glutamatergic transmission in rats would lead to impaired decision making in the PRL. Consistent with this hypothesis, compared to controls the postnatal PCP-treated rats completed fewer reversals and exhibited disruptions in reward and punishment sensitivity (i.e., win-stay and lose-shift responding, respectively). Moreover, computational analysis of behavior revealed that postnatal PCP-treatment resulted in a pronounced impairment in the learning rate throughout PRL testing. Finally, a deep neural network (DNN) trained on the rodent behavior could accurately predict the treatment group of subjects. These data demonstrate that disrupting early postnatal glutamatergic neurotransmission impairs flexible decision making and provides evidence that DNNs can be trained on behavioral datasets to accurately predict the treatment group of new subjects, highlighting the potential for DNNs to aid in the diagnosis of schizophrenia.


Subject(s)
Phencyclidine , Schizophrenia , Animals , Rats , Phencyclidine/pharmacology , Schizophrenia/chemically induced , Reversal Learning , Synaptic Transmission , Reward
19.
Pharmacol Biochem Behav ; 222: 173499, 2023 01.
Article in English | MEDLINE | ID: mdl-36462584

ABSTRACT

Although antiretroviral therapy (ART) has increased the quality of life and lifespan in people living with HIV (PWH), millions continue to suffer from the neurobehavioral effects of the virus. Additionally, the abuse of illicit drugs (methamphetamine in particular) is significantly higher in PWH compared to the general population, which may further impact their neurological functions. The HIV regulatory protein, Tat, has been implicated in the neurobehavioral impacts of HIV and is purported to inhibit dopamine transporter (DAT) function in a way similar to methamphetamine. Thus, we hypothesized that a combination of Tat expression and methamphetamine would exert synergistic deleterious effects on behavior and DAT expression. We examined the impact of chronic methamphetamine exposure on exploration in transgenic mice expressing human Tat (iTat) vs. their wildtype littermates using the behavioral pattern monitor (BPM). During baseline, mice exhibited sex-dependent differences in BPM behavior, which persisted through methamphetamine exposure, and Tat activation with doxycycline. We observed a main effect of methamphetamine, wherein exposure, irrespective of genotype, increased locomotor activity and decreased specific exploration. After doxycycline treatment, mice continued to exhibit drug-dependent alterations in locomotion, with no effect of Tat, or methamphetamine interactions. DAT levels were higher in wildtype, saline-exposed males compared to all other groups. These data support stimulant-induced changes of locomotor activity and exploration, and suggest that viral Tat and methamphetamine do not synergistically interact to alter these behaviors in mice. These findings are important for future studies attempting to disentangle the effect of substances that impact DAT on HAND-relevant behaviors using such transgenic animals.


Subject(s)
HIV Infections , Methamphetamine , Male , Mice , Humans , Animals , Mice, Transgenic , Methamphetamine/pharmacology , tat Gene Products, Human Immunodeficiency Virus/genetics , tat Gene Products, Human Immunodeficiency Virus/metabolism , tat Gene Products, Human Immunodeficiency Virus/pharmacology , Quality of Life , Doxycycline/pharmacology , Locomotion
20.
Cereb Cortex ; 33(10): 5783-5796, 2023 05 09.
Article in English | MEDLINE | ID: mdl-36472411

ABSTRACT

The balance between exploration and exploitation is essential for decision-making. The present study investigated the role of ventromedial orbitofrontal cortex (vmOFC) glutamate neurons in mediating value-based decision-making by first using optogenetics to manipulate vmOFC glutamate activity in rats during a probabilistic reversal learning (PRL) task. Rats that received vmOFC activation during informative feedback completed fewer reversals and exhibited reduced reward sensitivity relative to rats. Analysis with a Q-learning computational model revealed that increased vmOFC activity did not affect the learning rate but instead promoted maladaptive exploration. By contrast, vmOFC inhibition increased the number of completed reversals and increased exploitative behavior. In a separate group of animals, calcium activity of vmOFC glutamate neurons was recorded using fiber photometry. Complementing our results above, we found that suppression of vmOFC activity during the latter part of rewarded trials was associated with improved PRL performance, greater win-stay responding and selecting the correct choice on the next trial. These data demonstrate that excessive vmOFC activity during reward feedback disrupted value-based decision-making by increasing the maladaptive exploration of lower-valued options. Our findings support the premise that pharmacological interventions that normalize aberrant vmOFC glutamate activity during reward feedback processing may attenuate deficits in value-based decision-making.


Subject(s)
Prefrontal Cortex , Reward , Rats , Animals , Prefrontal Cortex/physiology , Reversal Learning/physiology , Glutamates , Decision Making/physiology
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