Modafinil: a review of neurochemical actions and effects on cognition

Modafinil/armodafinil for excessive daytime sleepiness after traumatic brain injury: a systematic review and meta-analysis

OBJECTIVES

Previous studies investigated pharmacological options for reducing excessive daytime sleepiness (EDS) after traumatic brain injury (TBI), with mixed results. This meta-analysis aimed to assess the efficacy and safety of modafinil or armodafinil in post-TBI persons experiencing EDS.

METHODS

We systematically searched PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov and identified studies comparing modafinil/armodafinil versus placebo for treating EDS after TBI. We computed pooled risk ratios (RR) or mean differences (MD) for binary and continuous outcomes, respectively. EDS was assessed using the Epworth Sleepiness Scale (ESS).

RESULTS

We included data from 158 individuals (mean age 34.28 years; 62.64% male) from three randomized controlled trials. In those treated with modafinil (dose range: 100-400 mg) or armodafinil (dose range: 150-250 mg), the mean ESS score was decreased in comparison with placebo (MD -1.65; 95% CI -3.26 to -0.04; p = 0.04). The risk of insomnia was higher in the modafinil/armodafinil group compared with the placebo group (RR 3.73; 95% CI 1.11 to 12.54; p = 0.03). There was no significant difference between groups in the risk of other adverse events (e.g., nausea, headache, dizziness, and nasopharyngitis).

CONCLUSION

Modafinil/armodafinil effectively improved EDS after TBI, as compared with placebo, albeit with an increased risk of insomnia.

Modafinil alters the functional connectivity of distinct thalamic nuclei with the neocortex

Modafinil promotes wakefulness and enhances cognitive function through mechanisms and neural effects that are still partially unknown. Several studies have shown that the compound alters the functional cortical architecture. In contrast, its influence on subcortical regions and thalamocortical connections, which are crucial for modulating neocortical connectivity, remains unexplored. The acute modulation of thalamo-cortical connectivity was assessed in two groups of participants who received either a single 100 mg dose of modafinil (N = 25) or a placebo (N = 25). Magnetic Resonance Imaging (MRI) was used to parcel the thalamus into its constituent nuclei, which served as seeds for voxel-wise resting state functional connectivity analyses. Additionally, maps of nuclei-specific functional reorganization were compared to those of receptor/transporter expression to assess their spatial overlaps. Modafinil, but not placebo, altered the connectivity of three thalamic nuclei. Specifically, the medial pulvinar nuclei showed increased connectivity with cortical regions of the Sensorimotor and Salience/Ventral Attention (SVAN) Networks. These functional changes spatially overlapped with the distribution of the norepinephrine transporter (NET). Additionally, the anterior and inferior pulvinar complex exhibited enhanced connectivity with the insular and supramarginal regions of the SVAN and superior frontal area of the Default Mode Network (DMN). However, unlike the medial pulvinar, these effects were not spatially linked to the expression of any specific receptor or transporter. Finally, the ventro-lateral anterior complex exhibited increased connectivity with the posterior region of the DMN and the Fronto-Parietal Control Network, along with decreased connectivity to the premotor cortex. The topography of these functional modifications mainly overlaps with the distribution of glutamatergic and serotonergic receptors. In summary, our findings highlight modafinil's influence on thalamocortical circuits, emphasizing the role of higher-order pulvinar nuclei and ventro-lateral anterior complex.

Transition-metal free chemoselective C-H hydroxylation of bisarylmethanes enabled by a phosphite as a sacrificial reductant

A transition-metal free (hetero)benzylic C-H hydroxylation approach for the synthesis of di(hetero)arylmethanols has been developed. The reaction is promoted by a KOtBu/DMSO/P(OEt)3 system, with atmospheric air as the sole oxidant at room temperature. This methodology has been employed to synthesize useful active pharmaceutical ingredients (APIs), modafinil and adrafinil. By using DMSO-d6 as the deuterium reagent, the hydroxylation-deuteration of 3-benzylpyridines and diphenylmethanes proceeded well, with excellent deuterium ratios. Preliminary kinetic experiments and 1H NMR studies provided significant insight into the reaction mechanism.

Repurposing of modafinil as an anti-inflammatory drug: a systematic review of experimental studies

Previous studies suggested the anti-inflammatory properties of modafinil. This study aimed to review the current literature to provide a comprehensive insight into the anti-inflammatory uses of modafinil in experimental studies. We conducted a systematic search using Medline (via PubMed), Web of Science, Scopus, and Embase databases from their commencement until 10 October 2022. All original articles focusing on modafinil anti-inflammatory effects were included. Our initial search yielded 1398 articles. Fourteen publications were included in our systematic review. Recent studies attempted to provide evidence for repurposing modafinil for several diseases, including autoimmune encephalomyelitis, nonalcoholic liver disease, gastric mucosal injury, neuropathic pain, atherosclerosis, intestinal ischemia, pulmonary hypertension, pancreatitis, ischemic stroke, testicular torsion, and lithium-pilocarpine-induced status epilepticus. Current evidence supports that modafinil can modulate inflammation, suppress the immune response, and improve disease severity partly by inhibiting NF-κB, NOS, Kca3.1, Kca2.3, and COX-2. By reviewing recent findings from experimental studies, we discussed the beneficial effects of modafinil on several inflammatory diseases, with a particular focus on the underlying mechanisms.

Modafinil Ameliorated Fibromyalgia Syndrome in Rats by Modulating Mast Cells and Microglia Activation Through Dopamine/Substance P/MRGPRX/Histamine and PI3K/p-Akt/NF-κB Signaling Pathways

Fibromyalgia syndrome (FMS) is characterized by prolonged, widespread musculoskeletal pain accompanied by various physical and psychological disturbances. Modafinil, a wake-promoting drug, manages pain symptoms in several diseases by inhibiting dopamine reuptake and exhibiting anti-inflammatory and immunomodulatory effects, including the impairment of cytokine production, microglia, and mast cell activation. Central inflammation may involve microglial activation, which is correlated with mast cell activation. Restoring dopamine levels and modulating the communication between mast cells and microglia may represent a promising approach to managing pain symptoms in FMS. Thus, this study intended to explore the interplay between brain mast cells and microglia as an underlying mechanism in the pathophysiology of FMS and how this interaction is controlled by modafinil, with a focus on dopamine/SP/MRGPRX2/histamine and PI3K/p-Akt/NF-κB signaling pathways. Rats were arbitrarily distributed between 4 groups. Group 1 served as normal control. Reserpine (1 mg/kg/day; s.c) was injected into the remaining groups for three consecutive days. In groups 3 and 4, modafinil (100 mg/kg/day; p.o) was administered either alone or in conjunction with haloperidol (1 mg/kg/day; ip), respectively, for the following 21 days. Modafinil ameliorated reserpine-induced thermal/mechanical allodynia (1.3-fold, 2.3-fold) and hyperalgesia (0.5-fold), attenuated depression (0.5-fold), and enhanced motor coordination (1.2-fold). It mitigated the histopathological alterations and increased dopamine levels in the thalamus of rats by 88.5%. Modafinil displayed anti-inflammatory effects via inhibiting mast cells and microglia activation, manifested by reductions in SP/MRGPRX2/IL-17/histamine (52%, 58%, 56.7%, and 63.7%) and PI3K/p-Akt/t-Akt/NF-κB/TNF-α/IL-6 (31.7%, 55.5%, 41%, 47.6%, and 76.9%), respectively. Ultimately, modafinil alleviated FMS behavioral, histopathological, and biochemical abnormalities and suppressed mast cell-microglial neuroinflammation in the thalamus of rats exposed to reserpine. This study highlights the potential of repurposing modafinil to improve FMS symptoms.

Modulation of Cerebellar-Cortical Connectivity Induced by Modafinil and Its Relationship With Receptor and Transporter Expression

BACKGROUND

Modafinil is primarily used to treat narcolepsy but is also used as an off-label cognitive enhancer. Functional magnetic resonance imaging studies indicate that modafinil modulates the connectivity of neocortical networks primarily involved in attention and executive functions. However, much less is known about the drug's effects on subcortical structures. Following preliminary findings, we evaluated modafinil's activity on the connectivity of distinct cerebellar regions with the neocortex. We assessed the spatial relationship of these effects with the expression of neurotransmitter receptors/transporters.

METHODS

Patterns of resting-state functional magnetic resonance imaging connectivity were estimated in 50 participants from scans acquired pre- and postadministration of a single (100 mg) dose of modafinil (n = 25) or placebo (n = 25). Using specific cerebellar regions as seeds for voxelwise analyses, we examined modafinil's modulation of cerebellar-neocortical connectivity. Next, we conducted a quantitative evaluation of the spatial overlap between the modulation of cerebellar-neocortical connectivity and the expression of neurotransmitter receptors/transporters obtained by publicly available databases.

RESULTS

Modafinil increased the connectivity of crus I and vermis IX with prefrontal regions. Crus I connectivity changes were associated with the expression of dopaminergic D2 receptors. The vermis I-II showed enhanced coupling with the dorsal anterior cingulate cortex and matched the expression of histaminergic H3 receptors. The vermis VII-VIII displayed increased connectivity with the visual cortex, an activity associated with dopaminergic and histaminergic neurotransmission.

CONCLUSIONS

Our study reveals modafinil's modulatory effects on cerebellar-neocortical connectivity. The modulation mainly involves crus I and the vermis and spatially overlaps the distribution of dopaminergic and histaminergic receptors.

The Issue of "Smart Drugs" on the Example of Modafinil: Toxicological Analysis of Evidences and Biological Samples

Cognitive enhancement through stimulants such as modafinil is becoming increasingly popular, with many individuals using prescription stimulants for non-medical purposes to improve alertness, attention, and mood. The misuse of such substances has raised concerns, particularly in forensic toxicology. The UHPLC-QqQ-MS/MS method was developed to quantify modafinil in evidentiary samples and biological materials. Additionally, the authors noted the presence of sodium adducts during the analysis of samples with high concentrations of modafinil. The method was validated for accuracy, precision, and linearity, with a concentration range of 0.1-10.0 µg/mL for the evidences and 1.0-100.0 ng/mL for blood. The method successfully detected modafinil as the sole substance in all evidences, with concentrations ranging from 90.7 to 120.8 mg, corresponding to 45.5% to 80.5% of the labeled dose. The method was applied to real post-mortem human cases, where, among others, the concentration of modafinil in blood was 110 ng/mL, whereas, in another case, the concentration of modafinil in the putrefaction fluid exceeded 1000 ng/mL. The developed UHPLC-QqQ-MS/MS method is effective for the quantification of modafinil in evidentiary samples and biological materials, offering a reliable tool for forensic toxicology applications. This method can be used to evaluate modafinil use in both legal and illicit contexts, including cases of overdose or misuse.

Diagnosing and treating hypersomnolence in depression

Hypersomnolence, a broad presentation encompassing excessive daytime sleepiness, hypersomnia and sleep inertia, affects around 25 % of patients with a major depressive disorder. Yet, hypersomnolence is often overlook in clinical settings - which can prevent remission of the mood disorder in addition to significantly interfering with quality of life. Clinical guidelines are lacking to support clinicians in the diagnosis and treatment of hypersomnolence in depression. Pharmacological treatment with selective serotonin reuptake inhibitors is insufficient and noradrenaline and dopamine reuptake inhibitors or similar molecules are generally indicated. Low-sodium oxybate was recently approved for Idiopathic Hypersomnia, but studies are needed to assess its efficacy in patients with comorbid depression. In parallel, cognitive behavioral therapy for hypersomnia is being developed as adjunct non-pharmacological treatment. Light therapy might also be beneficial in these populations. This narrative review aims at proposing a diagnostic approach reconciliating psychiatry and sleep medicine nosologies, as well as offering a multimodal treatment algorithm for hypersomnolence in depression.

The beneficial effects of modafinil administration on repeat mild traumatic brain injury (RmTBI) pathology in adolescent male rats are not dependent upon the orexinergic system

The sleep-wake cycle plays an influential role in the development and progression of repeat mild traumatic brain injury (RmTBI)-related pathology. Therefore, we first aimed to manipulate the sleep-wake cycle post-RmTBI using modafinil, a wake-promoting substance used for the treatment of narcolepsy. We hypothesized that modafinil would exacerbate RmTBI-induced deficits. Chronic behavioural analyses were completed along with a 27-plex serum cytokine array, metabolomic and proteomic analyses of cerebrospinal fluid (CSF), as well as immunohistochemical staining in structures important for sleep/wake cycles, to examine orexin, melanin-concentrating hormone, tyrosine hydroxylase, and choline acetyltransferase, in the lateral hypothalamus, locus coeruleus, and basal forebrain, respectively. Contrary to expectation, modafinil administration attenuated behavioural deficits, metabolomic changes, and neuropathological modifications. Therefore, the second aim was to determine if the beneficial effects of modafinil treatment were driven by the orexinergic system. The same experimental protocol was used; however, RmTBI rats received chronic orexin-A administration instead of modafinil. Orexin-A administration produced drastically different outcomes, exacerbating anxiety-related and motor deficits, while also significantly disrupting their metabolomic and neuropathological profiles. These results suggest that the beneficial effects of modafinil administration post-RmTBI, work independently of its wake-promoting properties, as activation of the orexinergic wake-promoting system with orexin-A was detrimental. Overall, these findings highlight the complexity of sleep-wake changes in the injured brain and showcase the potential of the arousal and sleep systems in its treatment.

Dopamine mediates a directionally opposite correlation between empathy and the reinforcing effects of amphetamine and gambling in people with gambling disorder vs. healthy controls

Understanding the relationship between empathy, subjective effects of addictive reinforcers and dopamine function in people with gambling disorder (PGD) vs. healthy controls (HCs) may inform GD treatment. The current investigation addressed this issue via retrospective analysis of data from three studies using amphetamine and a slot machine (SLOTS) as reinforcers in PGD and HCs. The Empathy scale of Eysenck's Impulsiveness Questionnaire assessed trait Empathy. The Gamblers Beliefs Questionnaire assessed cognitive distortions. The Eysenck Lie scale assessed socially desirable responding. PET scans quantified dopamine receptor expression and amphetamine-induced dopamine release in Study 1. Pre-treatment with the D2-receptor (D2R)-preferring antagonist, haloperidol or D1R-D2R antagonist, fluphenazine before SLOTS tested the role of D2 autoreceptors and post-synaptic D2R in Study 2. Pre-treatment with the multi-system indirect dopamine agonist, modafinil before SLOTS assessed the reliability of correlations in PGD. Striatal D2R expression predicted greater Empathy and lower amphetamine 'Liking' in HCs, and predicted greater symptom severity in PGD. Empathy predicted lower 'Exciting' effects of SLOTS under placebo in HCs; no correlation emerged under either antagonist. Relative to placebo, haloperidol decreased, whereas fluphenazine increased, the positive correlation between Empathy and Exciting effects of SLOTS in PGD. Modafinil markedly reduced the positive correlation between Empathy and Exciting effects of SLOTS seen under placebo in PGD. Empathy predicted greater cognitive distortions in PGD in all studies. Lie scale variance influenced several primary effects. Prior research linking the insula with Empathy, reactivity to interoceptive signals for risky rewards (uncertainty), and cognitive distortions, provides a parsimonious account for these results.

Caffeine and modafinil modulate the effects of sleep deprivation on thalamic resting-state functional connectivity: A double-blind pilot study

BACKGROUND

Studies have found that the use of clinically approved caffeine and modafinil can alleviate cognitive impairment due to sleep deprivation (SD) to some extent. However, the neural mechanisms by which these two cognitive enhancers work to counteract the effects of SD on cognitive impairment remain unclear.

METHODS

A double-blind within-subjects experiment using resting-state functional magnetic resonance imaging (rs-fMRI) was designed. Participants underwent three 36-h SD trials, each of which involved taking 200 mg of caffeine, modafinil, or placebo at the 28th and 32 nd h of SD. Sixteen subregions of the thalamus were selected as the regions of interest and changes in functional connectivity (FC) between the thalamus and the other brain regions were explored after the participants took caffeine or modafinil.

RESULTS

The subjective sleepiness of the participants increased with the duration of SD. compared with placebo, modafinil and caffeine had insignificant effects on wakefulness or sleepiness. However, in terms of neural FC, we found varying degrees of attenuation or enhancement of the FC between the thalamus and other regions. Taking caffeine during SD weakened the FC between the right rostral temporal thalamus (rTtha) subregion and the left lingual gyrus compared with placebo. Caffeine enhanced the FC between three subregions of the thalamus, namely the left sensory thalamus, the left rTtha, and the right lateral pre-frontal thalamus, and the right inferior temporal, left orbitofrontal, and right superior occipital gyris. Modafinil weakened the FC between the right posterior parietal thalamus and left middle temporal gyrus, and enhanced the FC between the left medial pre-frontal thalamus, left rTtha, and right occipital thalamus and left middle frontal gyrus.

CONCLUSIONS

After 36 h of total SD, modafinil and caffeine administration enhanced or attenuated the time-domain correlations between various subregions of the thalamus and brain regions of the frontal and temporal lobes in healthy adults, compared with placebo. These results provide valuable evidence for further unraveling the neuropharmacological mechanisms of caffeine and modafinil, as well as important insights for exploring effective pharmacological intervention strategies against SD.

A randomized placebo controlled trial demonstrates the effect of dl-methylephedrine on brain functions is weaker than that of pseudoephedrine

Intellectual drug doping in athletics by using stimulants that affect central nervous system functions has been diversified. Stimulants are regulated by the World Anti-Doping Agency according to their levels of urinary concentration. Positron emission tomography could evaluate how stimulants affect central nervous system functions. We aimed to evaluate the effect of stimulants on brain function by examining the difference in brain dopamine transporter occupancy by PET after administration of dl-methylephedrine or pseudoephedrine at the clinical maximum daily dose. Four PET scans without and with drug administration (placebo, dl-methylephedrine 150 mg and pseudoephedrine 240 mg) were performed. The concentrations of dl-methylephedrine and pseudoephedrine in plasma and urine were measured. DAT occupancies in the striatum with placebo, dl-methylephedrine and pseudoephedrine were calculated by PET images. The urinary concentration of dl-methylephedrine (12.7 µg/mL) exceeded the prohibited concentration (10 µg/mL), but the DAT occupancy with dl-methylephedrine (6.1%) did not differ (p = 0.92) from that with placebo (6.2%). By contrast, although the urinary concentration of pseudoephedrine (144.8 µg/mL) was below the prohibited concentration (150 μg/mL), DAT occupancy with pseudoephedrine was 18.4%, which was higher than that with placebo (p = 0.009). At the maximum clinical dose, dl-methylephedrine was shown to have weaker effects on brain function than pseudoephedrine.

Insomnia-related rodent models in drug discovery

Despite the widespread prevalence and important medical impact of insomnia, effective agents with few side effects are lacking in clinics. This is most likely due to relatively poor understanding of the etiology and pathophysiology of insomnia, and the lack of appropriate animal models for screening new compounds. As the main homeostatic, circadian, and neurochemical modulations of sleep remain essentially similar between humans and rodents, rodent models are often used to elucidate the mechanisms of insomnia and to develop novel therapeutic targets. In this article, we focus on several rodent models of insomnia induced by stress, diseases, drugs, disruption of the circadian clock, and other means such as genetic manipulation of specific neuronal activity, respectively, which could be used to screen for novel hypnotics. Moreover, important advantages and constraints of some animal models are discussed. Finally, this review highlights that the rodent models of insomnia may play a crucial role in novel drug development to optimize the management of insomnia.

Contributions of network structure, chemoarchitecture and diagnostic categories to transitions between cognitive topographies

The mechanisms linking the brain's network structure to cognitively relevant activation patterns remain largely unknown. Here, by leveraging principles of network control, we show how the architecture of the human connectome shapes transitions between 123 experimentally defined cognitive activation maps (cognitive topographies) from the NeuroSynth meta-analytic database. Specifically, we systematically integrated large-scale multimodal neuroimaging data from functional magnetic resonance imaging, diffusion tractography, cortical morphometry and positron emission tomography to simulate how anatomically guided transitions between cognitive states can be reshaped by neurotransmitter engagement or by changes in cortical thickness. Our model incorporates neurotransmitter-receptor density maps (18 receptors and transporters) and maps of cortical thickness pertaining to a wide range of mental health, neurodegenerative, psychiatric and neurodevelopmental diagnostic categories (17,000 patients and 22,000 controls). The results provide a comprehensive look-up table charting how brain network organization and chemoarchitecture interact to manifest different cognitive topographies, and establish a principled foundation for the systematic identification of ways to promote selective transitions between cognitive topographies.

Pharmacological Treatments for Methamphetamine Use Disorder: Current Status and Future Targets

The illicit use of the psychostimulant methamphetamine (METH) is a major concern, with overdose deaths increasing substantially since the mid-2010s. One challenge to treating METH use disorder (MUD), as with other psychostimulant use disorders, is that there are no available pharmacotherapies that can reduce cravings and help individuals achieve abstinence. The purpose of the current review is to discuss the molecular targets that have been tested in assays measuring the physiological, the cognitive, and the reinforcing effects of METH in both animals and humans. Several drugs show promise as potential pharmacotherapies for MUD when tested in animals, but fail to produce long-term changes in METH use in dependent individuals (eg, modafinil, antipsychotic medications, baclofen). However, these drugs, plus medications like atomoxetine and varenicline, may be better served as treatments to ameliorate the psychotomimetic effects of METH or to reverse METH-induced cognitive deficits. Preclinical studies show that vesicular monoamine transporter 2 inhibitors, metabotropic glutamate receptor ligands, and trace amine-associated receptor agonists are efficacious in attenuating the reinforcing effects of METH; however, clinical studies are needed to determine if these drugs effectively treat MUD. In addition to screening these compounds in individuals with MUD, potential future directions include increased emphasis on sex differences in preclinical studies and utilization of pharmacogenetic approaches to determine if genetic variances are predictive of treatment outcomes. These future directions can help lead to better interventions for treating MUD.

Chronic administration of caffeine, modafinil, AVL-3288 and CX516 induces time-dependent complex effects on cognition and mood in an animal model of sleep deprivation

OBJECTIVE

Caffeine and modafinil are used to reverse effects of sleep deprivation. Nicotinic alpha-7 receptor and AMPA receptor positive allosteric modulators (PAM) are also potential substances in this context. Our objective is to evaluate the effects of caffeine, modafinil, AVL-3288 (nicotinic alpha-7 PAM) and CX516 (AMPA receptor PAM) on cognition and mood in a model of sleep deprivation.

METHOD

Modified multiple platform model is used to sleep-deprive mice for 24 days, for 8 h/day. Vehicle, Modafinil (40 mg/kg), Caffeine (5 mg/kg), CX516 (10 mg/kg), and AVL3288 (1 mg/kg) were administered intraperitoneally daily. A cognitive test battery was applied every six days for four times. The battery that included elevated plus maze, novel object recognition, and sucrose preference tests was administered on consecutive days.

RESULTS

Sleep deprivation decreased novel object recognition skill, but no significant difference was found in anxiety and depressive mood. Caffeine administration decreased anxiety-like behavior in short term, but this effect disappeared in chronic administration. Caffeine administration increased memory performance in chronic period. AVL group showed better memory performance in short term, but this effect disappeared in the rest of experiment. Although, in the modafinil group, no significant change in mood and memory was observed, anhedonia was observed in the chronic period in vehicle, caffeine and modafinil groups, but not in AVL-3288 and CX-516 groups.

CONCLUSION

Caffeine has anxiolytic effect in acute administration. The improvement of memory in chronic period may be associated with the neuroprotective effects of caffeine. AVL-3288 had a short-term positive effect on memory, but tolerance to these effects developed over time. Furthermore, no anhedonia was observed in AVL-3288 and CX516 groups in contrast to vehicle, caffeine and modafinil groups. This indicates that AVL-3288 and CX516 may show protective effect against depression.

Effects of modafinil on nocturnal sleep patterns in patients with narcolepsy: A cohort study

BACKGROUND

Patients with narcolepsy often experience disturbed nighttime sleep. Modafinil is commonly prescribed for hypersomnolence, but its impacts on nocturnal sleep remain unclear. This study uses actigraphy to examine the effect of modafinil on both hypersomnolence and nocturnal sleep patterns in patients with narcolepsy.

METHODS

Prior to treatment, 87 patients with narcolepsy wore an actigraphy for 7-14 days to assess their nighttime sleep. After evaluation, they received a daily dose of 200-400 mg of modafinil in the morning and wore an actigraphy again six months after initiating treatment. Questionnaires, including the Epworth-Sleepiness-Scale (ESS), the Visual-Analogue-for-Hypersomnolence (VAS), and the Short-Form-36-Health-Survey (SF-36), were used to evaluate hypersomnolence and quality of life both before and after treatment. Paired t-tests and independent samples t-tests were used for pre- and post-treatment comparisons and subgroup analysis. We used the Pearson's correlation test to measure the correlations between the sleep parameters of the actigraphy and data of the questionnaires.

RESULTS

Improvements in hypersomnolence were noted following modafinil treatment, and we observed no significant deterioration in nocturnal sleep parameters by the actigraphy. The total number of awakenings by actigraphy significantly decreased (p = 0.005), especially in females (p = 0.008), while sleep onset latency significantly increased in children/adolescents (p = 0.014). Correlations were found between the sleep parameters of the actigraphy and ESS, VAS, and SF-36 scores.

CONCLUSION

Modafinil treatment may not worsen nighttime sleep in patients with narcolepsy. However, it should be administered with care in children and adolescents.

Application of novel metal organic framework-deep eutectic solvent/molecularly imprinted polymer multiple monolithic fiber for solid phase microextraction of amphetamines and modafinil in unauthorized medicinal supplements with GC-MS

The goal of this research is the development of multiple monolithic fiber-solid phase microextraction (MMF-SPME) using a new integrated fiber for the determination of amphetamine derivatives and modafinil from unauthorized medicinal supplements. For this purpose, a monolithic fiber of metal organic framework MIL-Al (53)-deep eutectic solvent (DES)/molecularly imprinted polymers (MOF-DES/MIP) was synthesized. To find optimum microextraction conditions gas chromatography-mass spectrometer (GC-MS) was used and the influences of effective variables were investigated using one factor at a time method. After that, the significant variables were optimized using a Box-Behnken design (BBD) combined with a desirability function (DF). Under optimized conditions (desorption solvent=1500 µL of 1-octanol, pH=3.5, extraction time=35 min, [NaCl]=0% w/v and stirring rate=600 rpm), calibration graphs of analytes were linear in a concentration range of 0.1-400 μg L-1 with correlation coefficients > 0.9966. Limits of detection and quantification were in the ranges of 0.023-0.033 μg L-1 and 0.088-0.113 μg L-1, respectively. This procedure was successfully employed in determining target analytes in spiked and unspiked unauthorized medicinal supplement samples with recoveries ranging from 95.14 to 104.63%.

Modafinil Therapy and Mental Status Following Aneurysmal Subarachnoid Hemorrhage: Comprehensive Stroke Center Analysis

BACKGROUND

Disorders of consciousness impair early recovery after aneurysmal subarachnoid hemorrhage (aSAH). Modafinil, a wakefulness-promoting agent, is efficacious for treating fatigue in stroke survivors, but data pertaining to its use in the acute setting are scarce. This study sought to assess the effects of modafinil use on mental status after aSAH.

METHODS

Modafinil timing and dosage, neurological examination, intubation status, and physical and occupational therapy participation were documented. Repeated-measures paired tests were used for a before-after analysis of modafinil recipients. Propensity score matching (1:1 nearest neighbor) for modafinil and no-modafinil cohorts was used to compare outcomes.

RESULTS

Modafinil (100-200 mg/day) was administered to 21% (88/422) of aSAH patients for a median (IQR) duration of 10.5 (4-16) days and initiated 14 (7-17) days after aSAH. Improvement in mentation (alertness, orientation, or Glasgow Coma Scale score) was documented in 87.5% (77/88) of modafinil recipients within 72 hours and 86.4% (76/88) at discharge. Of 37 intubated patients, 10 (27%) were extubated within 72 hours after modafinil initiation. Physical and occupational therapy teams noted increased alertness or participation in 47 of 56 modafinil patients (83.9%). After propensity score matching for baseline covariates, the modafinil cohort had a greater mean (SD) change in Glasgow Coma Scale score than the no-modafinil cohort at discharge (2.2 [4.0] vs. -0.2 [6.32], P = 0.003).

CONCLUSIONS

A temporal relationship with improvement in mental status was noted for most patients administered modafinil after aSAH. These findings, a favorable adverse-effect profile, and implications for goals-of-care decisions favor a low threshold for modafinil initiation in aSAH patients in the acute-care setting.

Using caffeine as a chemical means to induce flow states

Flow is an intrinsically rewarding state characterised by positive affect and total task absorption. Because cognitive and physical performance are optimal in flow, chemical means to facilitate this state are appealing. Caffeine, a non-selective adenosine receptor antagonist, has been emphasized as a potential flow-inducer. Thus, we review the psychological and biological effects of caffeine that, conceptually, enhance flow. Caffeine may facilitate flow through various effects, including: i) upregulation of dopamine D1/D2 receptor affinity in reward-associated brain areas, leading to greater energetic arousal and 'wanting'; ii) protection of dopaminergic neurons; iii) increases in norepinephrine release and alertness, which offset sleep-deprivation and hypoarousal; iv) heightening of parasympathetic high frequency heart rate variability, resulting in improved cortical stress appraisal, v) modification of striatal endocannabinoid-CB1 receptor-signalling, leading to enhanced stress tolerance; and vi) changes in brain network activity in favour of executive function and flow. We also discuss the application of caffeine to treat attention deficit hyperactivity disorder and caveats. We hope to inspire studies assessing the use of caffeine to induce flow.

Hemerocallis citrina Baroni ameliorates chronic sleep deprivation-induced cognitive deficits and depressive-like behaviours in mice

Sleep deprivation (SD) is common during spaceflight. SD is known to cause cognitive deficits and depression, requiring treatment and prevention. Hemerocallis citrina Baroni (Liliaceae) is a perennial herb with antidepressant, antioxidant, antitumor, anti-inflammatory, and neuroprotective effects.The aim of our study was to investigate the effects of H. citrina extract (HCE) on SD-induced cognitive decline and depression-like behavior and possible neuroinflammation-related mechanisms. HCE (2 g/kg/day, i.g.) or vortioxetine (10 mg/kg/day, i.g.) were given to mice by oral gavage for a total of 28 days during the SD process. HCE treatment was found to ameliorate SD-induced impairment of short- and long-term spatial and nonspatial memory, measured using Y-maze, object recognition, and Morris water maze tests, as well as mitigating SD-induced depression-like behaviors, measured by tail suspension and forced swimming tests. HCE also reduced the levels of inflammatory cytokines (IL-1β, IL-18, and IL-6) in the serum and hippocampus. Furthermore, HCE suppressed SD-induced microglial activation in the prefrontal cortex (PFC) and the CA1 and dentate gyrus (DG) regions of the hippocampus. HCE also inhibited the expression of phosphorylated NF-κB and activation of the NLRP3 inflammasome. In summary, our findings indicated that HCE attenuated SD-induced cognitive impairment and depression-like behavior and that this effect may be mediated by the inhibition of inflammatory progression and microglial activation in the hippocampus, as well as the down-regulation of NF-κB and NLRP3 signaling. The findings of these studies showingTthese results indicate that HCE exerts neuroprotective effects and are consistent with the findings of previous studies, suggesting that HCE is beneficial for the prevention and treatment of cognitive decline and depression in SD.

Apathy and Motivation: Biological Basis and Drug Treatment

Apathy is a disabling syndrome associated with poor functional outcomes that is common across a broad range of neurological and psychiatric conditions. Currently, there are no established therapies specifically for the condition, and safe and effective treatments are urgently needed. Advances in the understanding of motivation and goal-directed behavior in humans and animals have shed light on the cognitive and neurobiological mechanisms contributing to apathy, providing an important foundation for the development of new treatments. Here, we review the cognitive components, neural circuitry, and pharmacology of apathy and motivation, highlighting converging evidence of shared transdiagnostic mechanisms. Though no pharmacological treatments have yet been licensed, we summarize trials of existing and novel compounds to date, identifying several promising candidates for clinical use and avenues of future drug development.

Selenium alleviates modafinil-induced neurobehavioral toxicity in rat via PI3K/Akt/mTOR/GSK3B signaling pathway and suppression of oxidative stress and apoptosis: in vivo and in silico study

Nonmedical use of modafinil (MOD) led to increased rates of overdose toxicity, road accidents, addiction, withdrawal, suicide, and mental illnesses. The current study aims to determine the probable MOD brain toxicity and elucidate the possible role of selenium (Se) in ameliorating the neurotoxicity in rat models. Fifty-four male Albino rats were randomly assigned into nine groups. The groups were G1 (control negative), G2 (Se0.1), G3 (Se0.2), G4 (MOD300), G5 (MOD600), G6 (Se0.1 + MOD300), G7 (Se0.2 + MOD300), G8 (Se0.1 + MOD600), and G9 (Se0.2 + MOD600). After finishing the experiment, blood and brain tissue were harvested for biochemical and histological investigation. Neurobehavior parameters were assessed. Tissue neurotransmitter levels and oxidative stress markers were assessed. Gene expression of PI3K/Akt/mTOR-GSK3B, orexin, and orexin receptor2 was measured by qRT-PCR. Histological and immunohistochemistry assessments, as well as molecular docking, were carried out. MOD-induced neurobehavioral toxicity exhibited by behavioral and cognitive function impairments, which are associated with decreased antioxidant activities, increased MDA levels, and decreases in neurotransmitter levels. Brain levels of mRNA expression of PI3K, Akt, and mTOR were decreased, while GS3K, orexin, and orexin receptors were significantly elevated. These disturbances were confirmed by histopathological brain changes with increased silver and Bax immunostaining and decreased crystal violet levels. MOD induced neurotoxic effects in a dose-dependent manner. Compared with the MOD groups, SE coadministration significantly attenuates MOD-induced toxic changes. Docking study shows the protective role of Se as an apoptosis inhibitor and inflammation inhibitor. In conclusion, Se could be used as a biologically effective antioxidant compound to protect from MOD neurobehavioral toxicity in Wistar rats by reversing behavioral alterations, inflammation, apoptosis, and oxidative injury.

Armodafinil as a Potential Pharmacological Treatment for Attention Deficit Hyperactivity Disorder in Adults: A Review

INTRODUCTION

Armodafinil is a psychostimulant that promotes alertness, and it has been shown to improve attention, memory, and fatigue in healthy adults and adults with neurodevelopmental conditions that share symptoms with Attention Deficit Hyperactivity Disorder (ADHD). It is generally well tolerated and safe, and most of the adverse events reported are considered not serious. However, the available evidence on the efficacy of armodafinil for the treatment of ADHD in adults is scarce.

OBJECTIVE

The present review aims to perform a systematized search of the available evidence on the possible therapeutic benefit of armodafinil treatment in adult patients with ADHD.

METHODS

A literature review using PubMed was conducted to compile and summarize the available clinical and scientific evidence on the possible use of armodafinil as a pharmacological treatment in adult patients with ADHD.

RESULTS

From the 86 articles reviewed, the available evidence showed that both acute and chronic treatment with armodafinil can improve wakefulness, memory, impulse control, and executive functions in adults with sleep disorders and other conditions. In addition, evidence of improvement in cognitive functions and mood alterations in other neuropsychiatric conditions was shown.

CONCLUSION

Armodafinil could be useful for the treatment of ADHD in adults, according to the review of the literature from both pre-clinical and clinical studies.

Manipulation of phasic arousal by auditory cues is associated with subsequent changes in visual orienting to faces in infancy

This eye-tracking study investigated the effect of sound-induced arousal on social orienting under different auditory cue conditions in 5-month-old (n = 25; n = 13 males) and 10-month-old infants (n = 21; n = 14 males) participating in a spontaneous visual search task. Results showed: (1) larger pupil dilation discriminating between high and low volume (b = 0.02, p = 0.007), but not between social and non-social sounds (b = 0.004, p = 0.64); (2) faster visual orienting (b =  - 0.09, p < 0.001) and better social orienting at older age (b = 0.94, p < 0.001); (3) a fast habituation effect on social orienting after high-volume sounds (χ2(2) = 7.39, p = 0.025); (4) a quadratic association between baseline pupil size and target selection (b =  - 1.0, SE = 0.5, χ2(1) = 4.04, p = 0.045); (5) a positive linear association between pupil dilation and social orienting (b = 0.09, p = 0.039). Findings support adaptive gain theories of arousal, extending the link between phasic pupil dilation and task performance to spontaneous social orienting in infancy.

Pitolisant-supported bridging during drug holidays to deal with tolerance to modafinil in patients with narcolepsy

STUDY OBJECTIVES

Modafinil is a common treatment for excessive daytime sleepiness (EDS) in narcolepsy. The long-term use of modafinil can lead to tolerance with the loss of efficacy and the continuous increase of its dose. Pharmacological strategies to deal with the tolerance to modafinil are lacking. We investigated the efficacy and safety of pitolisant-supported bridging during drug holidays in patients with tolerance to modafinil.

METHODS

Narcolepsy patients on monotherapy with modafinil who developed symptoms of tolerance were eligible. The following alternating therapy regimen was established: Monday to Friday patients continued on modafinil whereas Saturday and Sunday they switched to pitolisant to "bridge" the EDS symptoms. Patients were assessed at baseline and after three months with the Epworth Sleepiness Scale (ESS) and the Ullanlinna Narcolepsy Scale (UNS). Health-related quality of life (HrQol) was evaluated by EuroQol5D. Adverse events were documented in the patients' diaries.

RESULTS

41 patients aged 30.9 ± 5.6 years were included. After three months of the alternating therapy regimen, the symptoms of tolerance decreased and the modafinil dose could be reduced by 41% (p < 0.01) resulting in better safety. The EDS improved on ESS (baseline: 18.2 ± 4.2, follow-up: 12.6 ± 4.0, p < 0.0001) and UNS (baseline: 25.8 ± 7.9, follow-up: 18.9 ± 5.9, p < 0.0001). The HrQol increased significantly.

CONCLUSION

Patients with tolerance to modafinil could benefit from pitolisant-supported bridging during drug holidays. This alternating pharmacological strategy proved to be safe and helped to reduce EDS and to decrease the modafinil dose. Further randomized controlled studies are required to evaluate the different strategies to deal with the tolerance to modafinil.

CLINICAL TRIAL REGISTRATION NUMBER

Clinical Trials.gov Identifier NCT05321355.

Pharmacokinetics of Novel Dopamine Transporter Inhibitor CE-123 and Modafinil with a Focus on Central Nervous System Distribution

S-CE-123, a novel dopamine transporter inhibitor, has emerged as a potential candidate for cognitive enhancement. The objective of this study was to compare the tissue distribution profiles, with a specific focus on central nervous system distribution and metabolism, of S-CE-123 and R-modafinil. To address this objective, a precise liquid chromatography-high resolution mass spectrometry method was developed and partially validated. Neuropharmacokinetic parameters were assessed using the Combinatory Mapping Approach. Our findings reveal distinct differences between the two compounds. Notably, S-CE-123 demonstrates a significantly superior extent of transport across the blood-brain barrier (BBB), with an unbound brain-to-plasma concentration ratio (Kp,uu,brain) of 0.5, compared to R-modafinil's Kp,uu,brain of 0.1. A similar pattern was observed for the transport across the blood-spinal cord barrier. Concerning the drug transport across cellular membranes, we observed that S-CE-123 primarily localizes in the brain interstitial space, whereas R-modafinil distributes more evenly across both sides of the plasma membrane of the brain's parenchymal cells (Kp,uu,cell). Furthermore, our study highlights the substantial differences in hepatic metabolic stability, with S-CE-123 having a 9.3-fold faster metabolism compared to R-modafinil. In summary, the combination of improved BBB transport and higher affinity of S-CE-123 to dopamine transporters in comparison to R-modafinil makes S-CE-123 a promising candidate for further testing for the treatment of cognitive decline.

Modafinil, an atypical CNS stimulant?

Modafinil is a central nervous system stimulant approved for the treatment of narcolepsy and sleep disorders. Due to its wide range of biochemical actions, modafinil has been explored for other potential therapeutic uses. Indeed, it has shown promise as a therapy for cognitive disfunction resulting from neurologic disorders like ADHD, and as a smart drug in non-medical settings. The mechanism(s) of actions underlying the therapeutic efficacy of this agent remains largely elusive. Modafinil is known to inhibit the dopamine transporter, thus decreasing dopamine reuptake following neuronal release, an effect shared by addictive psychostimulants. However, modafinil is unique in that only a few cases of dependence on this drug have been reported, as compared to other psychostimulants. Moreover, modafinil has been tested, with some success, as a potential therapeutic agent to combat psychostimulant and other substance use disorders. Modafinil has additional, but less understood, actions on other neurotransmitter systems (GABA, glutamate, serotonin, norepinephrine, etc.). These interactions, together with its ability to activate selected brain regions, are likely one of the keys to understand its unique pharmacology and therapeutic activity as a CNS stimulant. In this chapter, we outline the pharmacokinetics and pharmacodynamics of modafinil that suggest it has an "atypical" CNS stimulant profile. We also highlight the current approved and off label uses of modafinil, including its beneficial effects as a treatment for sleep disorders, cognitive functions, and substance use disorders.

Open-label placebo treatment does not enhance cognitive abilities in healthy volunteers

The use of so-called 'smart drugs' such as modafinil to improve cognitive performance has recently attracted considerable attention. However, their side effects have limited user enthusiasm. Open-label placebo (OLP) treatment, i.e., inert treatments that are openly disclosed to individuals as having no active pharmacological ingredient, has been shown to improve various medical symptoms and conditions, including those related to cognitive performance. OLP treatment could therefore be an exciting alternative to pharmacological cognitive enhancers. Here, we used a randomized-controlled design to investigate the effect of a 21-day OLP treatment on several sub-domains of cognitive performance in N = 78 healthy volunteers. Subjective and objective measures of cognitive performance as well as different measures of well-being were obtained before and after the treatment period. Using a combination of classic Frequentist and Bayesian analysis approaches showed no additional benefit from OLP treatment in any of the subjective or objective measures of cognitive performance. Our study thus highlights possible limitations of OLP treatment in boosting cognitive performance in healthy volunteers. These findings are discussed in the light of expectancy-value considerations that may determine OLP efficacy.

A novel mesna-based electrochemical sensor embellished with silver nanoparticles for ultrasensitive analysis of modafinil

Modafinil (MOD) is a CNS stimulant used for the treatment of narcolepsy, shift work sleep disorder, excessive daytime sleepiness, and post-COVID 19 neurological symptoms. In the literature, there is no report of square wave voltammetric (SWV) methods being used for the determination of MOD. This study describes, for the first time, the construction and evaluation of the analytical performance of a novel sensor for ultrasensitive SWV detection of MOD. The sensor was constructed by integration of silver nanoparticles (AgNPs) on Mesna (MSN) layers over a pencil graphite electrode (PGE) surface. The interface and morphological characteristics of the fabricated AgNPs@MSN/PGE sensor were investigated via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). This sensor was found to enhance the electro-oxidation of MOD. The combination of AgNPs@MSN/PGE with SWV enabled the determination of MOD in its bulk form and in pharmaceutical and biological matrices at the nanomolar scale (LOD = 28.59 nM) with excellent recoveries. This study represents the first report describing an electrochemical procedure for MOD detection in human plasma. The established SWV method was also validated, and the results were consistent with ICH criteria. Finally, the presented SWV procedure provides a facile, sensitive, rapid, and cost-effective approach compared to other existing methods.

Consciousness Recovery in Traumatic Brain Injury: A Systematic Review Comparing Modafinil and Amantadine

OBJECTIVES

Acute traumatic brain injury is one of the most common causes of death and disability. Reduction in the level of consciousness is a significant complication that can impact morbidity. Glasgow Coma Scale (GCS) is the most widely used method of assessing the level of consciousness. Neurostimulants such as amantadine and modafinil are common pharmacologic agents that increase GCS in patients with brain trauma. This study aimed to compare the effectiveness of these 2 drugs.

METHODS

This systematic review obtained articles from Google Scholar, PubMed, Scopus, Embase, and MEDLINE databases. Extensive searches were conducted separately by 4 individuals in 3 stages. Ultimately, 16 clinical trials, cohort studies, case reports, and case series articles were obtained after reading the title, abstract, and full text and considering the exclusion criteria. The data of the final article were entered into the analysis table. This study was registered with PROSPERO (registration number CRD42022334409) and conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Amantadine seems to be associated with a higher overall response rate. In contrast, modafinil is associated with the most remarkable change in GCS score during treatment. However, the number of clinical trials with high quality and sample size has not been satisfactory to compare the effectiveness of these 2 drugs and their potential side effects.

CONCLUSIONS

The authors recommend additional double-blind clinical trials are needed to be conducted with a larger sample size, comparing amantadine with modafinil to delineate the efficacy and adverse effects, both short and long term.

Neurochemical Effects of Methylphenidate and Modafinil in Ameliorating Stress-Induced Cognitive Deficits

PURPOSE

Chronic stressful situations result in altered monoaminergic activity of neurotransmitters, resulting in various conditions characterized by deficits in learning, memory and attention. Stimulant effects can be visualized in terms of increased cognitive abilities through enhancement of dopamine (DA) release.

METHOD

This study examined cognitive responses and brain DA and 5-hydroxytryptamine (5HT) levels after prolonged methylphenidate (MPH) and modafinil administration, to demonstrate their effect on stress-induced cognitive deficits in rats. Effects on cognition were evaluated by passive avoidance and water maze tests. Furthermore brain levels of DA, homovanillic acid (HVA), dihydroxyphenylacetic acid (DOPAC), 5HT and 5-hydroxyindoleacetic acid (5HIAA) were analyzed by high-performance liquid chromatography coupled with electrochemical detection.

RESULTS

We found that both MPH and modafinil improved cognition in both restrained and unrestrained rats, as examined through water maze and passive avoidance tests. Furthermore, these substance were associated with increased brain DA and 5-HT levels. Notabily, we observed decrease in DOPAC and HVA levels, while 5-HIAA levels exhibited a slight increase.

CONCLUSIONS

The prevention of stress-induced cognitive deficits by MPH and modafinil could be elucidated through the interaction between 5HT and DA in regulating cognitive function.

Modafinil's effects on cognition and sleep quality in affectively-stable patients with bipolar disorder: a pilot study

Introduction

Despite advances in the treatment of bipolar disorder (BD), most patients do not achieve complete inter-episode recovery and functional disability is common. During periods of relative remission, many patients continue to experience neurocognitive dysfunction, reduced daytime activity levels, and sleep disturbances. This 8-week, randomized, placebo-controlled pilot study evaluated the feasibility, safety and preliminary efficacy of the wake-promoting drug, modafinil (Provigil®), on neurocognitive functioning, daytime sleepiness, and sleep quality in affectively-stable BD patients.

Methods

Twelve individuals with affectively-stable BD were recruited and randomized to a flexible dose of modafinil (100 to 200 mg/day) or placebo, adjunctive to a therapeutic dose of a mood stabilizer. Weekly in-person visits tracked sleep quality and daytime sleepiness as well as side effects and mood symptoms. Neurocognitive functioning was assessed at baseline, week 4, and week 8.

Results

No serious adverse events were reported. Newly emergent side effects in the modafinil group included heart palpitations, itching, fatigue, and decreased energy. Two patients discontinued modafinil owing to side effects and one of these patients withdrew from the study. One patient discontinued placebo and was withdrawn from the study. Preliminary evaluations of clinical efficacy showed a marginally significant interaction between treatment group and time in two cognitive domains (speed of processing and verbal learning), indicating greater improvement in the modafinil group versus placebo. Additionally, there was a marginally significant effect of treatment group on daytime sleepiness, suggesting lower daytime sleepiness in the modafinil group versus placebo. Counterintuitively, we found a significant treatment group by time interaction effect on sleep quality, suggesting greater improvement in sleep quality in the placebo group versus the modafinil group.

Discussion

Results suggest that modafinil is a relatively safe medication for affectively-stable BD patients when given with adjunctive mood stabilizers. Results are suggestive of cognitive benefit and improved daytime sleepiness, but worse sleep quality in those patients prescribed modafinil. A fully powered clinical trial is warranted with specific attention to the characteristics of patients who are most likely to benefit from treatment with modafinil and other methodological lessons learned from this pilot.

Clinical trial registration

ClinicalTrials.gov, identifier NCT01965925.

Solriamfetol enhances wakefulness and improves cognition and anxiety in a murine model of OSA

BACKGROUND

Obstructive sleep apnea (OSA) is a chronic condition characterized by intermittent hypoxia (IH). Excessive daytime sleepiness (EDS) is a common consequence of OSA and is associated with cognitive deficits and anxiety. Modafinil (MOD) and Solriamfetol (SOL) are potent wake-promoting agents clinically used to improve wakefulness in OSA patients with EDS.

METHODS

Male C57Bl/6J mice were exposed to either IH or room air (RA) controls during the light phase for 16 weeks. Both groups were then randomly assigned to receive once-daily intraperitoneal injections of SOL (200 mg/kg), MOD (200 mg/kg) or vehicle (VEH) for 9 days while continuing IH exposures. Sleep/wake activity was assessed during the dark (active) phase. Novel object recognition (NOR), elevated-plus maze test (EPMT), and forced swim test (FST) were performed before and after drug treatment.

RESULTS

IH exposure increased dark phase sleep percentage and reduced wake bouts lengths and induced cognitive deficits and anxiogenic effects. Both SOL and MOD treatments decreased sleep propensity under IH conditions, but only SOL promoted improvements in NOR performance (explicit memory) and reduced anxiety-like behaviors.

CONCLUSION

Chronic IH, a hallmark feature of OSA, induces EDS in young adult mice that is ameliorated by both SOL and MOD. SOL, but not MOD, significantly improves IH-induced cognitive deficits and promotes anxiolytic effects. Thus, SOL could potentially benefit OSA patients beyond EDS management.

Modafinil Improves Autism-like Behavior in Rats by Reducing Neuroinflammation

To evaluate the ameliorating effect of Modafinil on neuroinflammation, behavioral, and histopathological alterations in rats induced by propionic acid (PPA). Thirty male Wistar rats were used in the study, divided into 3 groups of ten subjects. One group served as a control, the subjects in the other two were given 250 mg/kg/day of PPA by intraperitoneal injection over the course of 5 days to induce autism. The experimental design was as follows: Group 1: Normal control (orally-fed control, n = 10); Group 2 (PPA + saline, n = 10): PPA and 1 ml/kg/day % 0.9 NaCl saline via oral gavage; Group 3 (PPA + Modafinil, n = 10) PPA and 30 mg/kg/day Modafinil (Modiodal tablets 100 mg, Cephalon) via oral gavage. All of the groups were investigated for behavioral, biochemical, and histological abnormality. Autism-like behaviors were reduced significantly in the rats treated with PPA. TNF-α, Nerve Growth Factor (NGF), IL-17, IL-2, and NF-KB levels as well as MDA levels and lactate were significantly higher in those treated with PPA compared to the control group. Using immunohistochemical methods, the number of neurons and GFAP immunoreactivity was significantly altered in PPA-treated rats compared to the control. Using Magnetic Resonance Spectroscopy (MRS), we found that lactate levels were significantly higher in the PPA-treated rats, while creatinine levels were significantly decreased. In the rats administered with Modafinil, behavior, neuroinflammation, and histopathological changes brought about by PPA were significantly reversed. Our results demonstrate the potential role of Modafinil in ameliorating PPA-induced neuroinflammation in rats.

Report of a Work Group on Sluggish Cognitive Tempo: Key Research Directions and a Consensus Change in Terminology to Cognitive Disengagement Syndrome

OBJECTIVE

The aim of this work was 2-fold: (1) to evaluate current knowledge and identify key directions in the study of sluggish cognitive tempo (SCT); and (2) to arrive at a consensus change in terminology for the construct that reflects the current science and may be more acceptable to researchers, clinicians, caregivers, and patients.

METHOD

An international Work Group was convened that, in early 2021, compiled an online archive of all research studies on SCT and summarized the current state of knowledge, noted methodological issues, and highlighted future directions, and met virtually on 10 occasions in 2021 to discuss these topics and terminology.

RESULTS

Major progress has been made over the last decade in advancing our understanding of SCT across the following domains of inquiry: construct measurement and stability; genetic, environmental, pathophysiologic, and neuropsychological correlates; comorbid conditions; functional impairments; and psychosocial and medication interventions. Findings across these domains are summarized, and potential avenues to pursue in the next generation of SCT-related research are proposed. Following repeated discussions on terminology, the Work Group selected "cognitive disengagement syndrome" (CDS) to replace "SCT" as the name for this construct. This term was deemed to best satisfy considerations that should apply when selecting terms for a condition or syndrome, as it does not overlap with established terms for other constructs, is not offensive, and reflects the current state of the science.

CONCLUSION

It is evident that CDS (SCT) has reached the threshold of recognition as a distinct syndrome. Much work remains to further clarify its nature (eg, transdiagnostic factor, separate disorder, diagnostic specifier), etiologies, demographic factors, relations to other psychopathologies, and linkages to specific domains of functional impairment. Investigators are needed with interests and expertise spanning basic, clinical, and translational research to advance our understanding and to improve the lives of individuals with this unique syndrome.

Solriamfetol improves chronic sleep fragmentation-induced increases in sleep propensity and ameliorates explicit memory in male mice

Obstructive sleep apnea (OSA) is a highly prevalent condition characterized by episodes of partial or complete breath cessation during sleep that induces sleep fragmentation (SF). One of the frequent manifestations of OSA is the presence of excessive daytime sleepiness (EDS) associated with cognitive deficits. Solriamfetol (SOL) and modafinil (MOD) are wake-promoting agents commonly prescribed to improve wakefulness in OSA patients with EDS. This study aimed to assess the effects of SOL and MOD in a murine model of OSA characterized by periodic SF. Male C57Bl/6J mice were exposed to either control sleep (SC) or SF (mimicking OSA) during the light period (06:00 h to 18:00 h) for 4 weeks, which consistently induces sustained excessive sleepiness during the dark phase. Both groups were then randomly assigned to receive once-daily intraperitoneal injections of SOL (200 mg/kg), MOD (200 mg/kg), or vehicle for 1 week while continuing exposures to SF or SC. Sleep/wake activity and sleep propensity were assessed during the dark phase. Novel Object Recognition test, Elevated-Plus Maze Test, and Forced Swim Test were performed before and after treatment. SOL or MOD decreased sleep propensity in SF, but only SOL induced improvements in explicit memory, while MOD exhibited increased anxiety behaviors. Chronic SF, a major hallmark of OSA, induces EDS in young adult mice that is mitigated by both SOL and MOD. SOL, but not MOD, significantly improves SF-induced cognitive deficits. Increased anxiety behaviors are apparent in MOD-treated mice. Further studies aiming to elucidate the beneficial cognitive effects of SOL are warranted.

G protein-coupled receptors in neurodegenerative diseases and psychiatric disorders

Neuropsychiatric disorders are multifactorial disorders with diverse aetiological factors. Identifying treatment targets is challenging because the diseases are resulting from heterogeneous biological, genetic, and environmental factors. Nevertheless, the increasing understanding of G protein-coupled receptor (GPCR) opens a new possibility in drug discovery. Harnessing our knowledge of molecular mechanisms and structural information of GPCRs will be advantageous for developing effective drugs. This review provides an overview of the role of GPCRs in various neurodegenerative and psychiatric diseases. Besides, we highlight the emerging opportunities of novel GPCR targets and address recent progress in GPCR drug development.

Pharmacologic Management of Cognitive Disengagement Syndrome (CDS) and Implications for Attention-Deficit/Hyperactivity Disorder (ADHD) Treatment: Emerging Treatments and Recommendations for Future Research

Although the study of cognitive disengagement syndrome (CDS; previously called sluggish cognitive tempo) first emerged in the 1980s, very little is known about treating CDS or its impact on evidence-based interventions for attention-deficit/hyperactivity disorder (ADHD) with which it frequently co-occurs. The objective of this leading article was to investigate the existing evidence on medication treatment and CDS, including studies that have examined CDS response to medication and CDS as a moderator of ADHD treatment response. A total of seven studies were identified. At present, the limited existing literature suggests that psychostimulants such as methylphenidate and lisdexamfetamine, as well as atomoxetine, may improve CDS symptoms, although replication and research on related medications is needed. However, there are indications that CDS symptoms may predict a reduced response to methylphenidate in children with ADHD. Although untested, research on the neurobiological, neuropsychological, and behavioral correlates of CDS point to a possible benefit of other ADHD medications (e.g., guanfacine), medications that treat narcolepsy (e.g., modafinil), and medications traditionally used to treat depression and anxiety (e.g., viloxazine, bupropion, fluvoxamine), some of which have also recently been used in ADHD management. The article concludes with recommendations for future research on pharmacologic treatment and CDS.

An update on potential pharmacotherapies for cognitive impairment in bipolar disorder

INTRODUCTION

Cognitive impairment is a core feature of bipolar disorder (BD) that impedes recovery by preventing the return to optimal socio-occupational functioning and reducing quality of life. Presently, there are no efficacious treatments for cognitive impairment in BD, but many pharmacological interventions are being considered as they have the potential to target the underlying pathophysiology of the disorder.

AREAS COVERED

This review summarizes the available evidence for pharmacological interventions for cognitive impairment in bipolar disorder. We searched PubMed, MedLine, and PsycInfo from inception to December 1^st, 2022. Traditional treatments, such as lithium, anticonvulsants (lamotrigine), antipsychotics (aripiprazole, asenapine, cariprazine, lurasidone, and olanzapine), antidepressants (vortioxetine, fluoxetine, and tianeptine) and psychostimulants (modafinil), and emerging interventions, such as acetylcholinesterase inhibitors (galantamine and donepezil), dopamine agonists (pramipexole), erythropoietin, glucocorticoid receptor antagonists (mifepristone), immune modulators (infliximab, minocycline and doxycycline), ketamine, metabolic agents (insulin, metformin, and liraglutide), probiotic supplements, and Withania somnifera are discussed.

EXPERT OPINION

The investigation of interventions for cognitive impairment in BD is a relatively under-researched area. In the past, methodological pitfalls in BD cognition trials have also been a critical limiting factor. Expanding on the existing literature and identifying novel pharmacological and non-pharmacological treatments for cognitive impairment in BD should be a priority.

Transitions between cognitive topographies: contributions of network structure, neuromodulation, and disease

Patterns of neural activity underlie human cognition. Transitions between these patterns are orchestrated by the brain's network architecture. What are the mechanisms linking network structure to cognitively relevant activation patterns? Here we implement principles of network control to investigate how the architecture of the human connectome shapes transitions between 123 experimentally defined cognitive activation maps (cognitive topographies) from the NeuroSynth meta-analytic engine. We also systematically incorporate neurotransmitter receptor density maps (18 receptors and transporters) and disease-related cortical abnormality maps (11 neurodegenerative, psychiatric and neurodevelopmental diseases; N = 17 000 patients, N = 22 000 controls). Integrating large-scale multimodal neuroimaging data from functional MRI, diffusion tractography, cortical morphometry, and positron emission tomography, we simulate how anatomically-guided transitions between cognitive states can be reshaped by pharmacological or pathological perturbation. Our results provide a comprehensive look-up table charting how brain network organisation and chemoarchitecture interact to manifest different cognitive topographies. This computational framework establishes a principled foundation for systematically identifying novel ways to promote selective transitions between desired cognitive topographies.

Cognitive impairment after cancer treatment: mechanisms, clinical characterization, and management

Cognitive impairment is a debilitating side effect experienced by patients with cancer treated with systemically administered anticancer therapies. With around 19.3 million new cases of cancer worldwide in 2020 and the five year survival rate growing from 50% in 1970 to 67% in 2013, an urgent need exists to understand enduring side effects with severe implications for quality of life. Whereas cognitive impairment associated with chemotherapy is recognized in patients with breast cancer, researchers have started to identify cognitive impairment associated with other treatments such as immune, endocrine, and targeted therapies only recently. The underlying mechanisms are diverse and therapy specific, so further evaluation is needed to develop effective therapeutic interventions. Drug and non-drug management strategies are emerging that target mechanistic pathways or the cognitive deficits themselves, but they need to be rigorously evaluated. Clinically, consistent use of objective diagnostic tools is necessary for accurate diagnosis and clinical characterization of cognitive impairment in patients treated with anticancer therapies. This should be supplemented with clinical guidelines that could be implemented in daily practice. This review summarizes the recent advances in the mechanisms, clinical characterization, and novel management strategies of cognitive impairment associated with treatment of non-central nervous system cancers.

Low-Affinity/High-Selectivity Dopamine Transport Inhibition Sufficient to Rescue Cognitive Functions in the Aging Rat

The worldwide increase in cognitive decline, both in aging and with psychiatric disorders, warrants a search for pharmacological treatment. Although dopaminergic treatment approaches represent a major step forward, current dopamine transporter (DAT) inhibitors are not sufficiently specific as they also target other transporters and receptors, thus showing unwanted side effects. Herein, we describe an enantiomerically pure, highly specific DAT inhibitor, S-CE-123, synthetized in our laboratory. Following binding studies to DAT, NET and SERT, GPCR and kinome screening, pharmacokinetics and a basic neurotoxic screen, S-CE-123 was tested for its potential to enhance and/or rescue cognitive functions in young and in aged rats in the non-invasive reward-motivated paradigm of a hole-board test for spatial learning. In addition, an open field study with young rats was carried out. We demonstrated that S-CE-123 is a low-affinity but highly selective dopamine reuptake inhibitor with good bioavailability. S-CE-123 did not induce hyperlocomotion or anxiogenic or stereotypic behaviour in young rats. Our compound improved the performance of aged but not young rats in a reward-motivated task. The well-described impairment of the dopaminergic system in aging may underlie the age-specific effect. We propose S-CE-123 as a possible candidate for developing a tentative therapeutic strategy for age-related cognitive decline and cognitive dysfunction in psychiatric disorders.

Comparison of Solriamfetol and Modafinil on Arousal and Anxiety-Related Behaviors in Narcoleptic Mice

Wake-promoting agents are used for the management of excessive daytime sleepiness caused by narcolepsy. Clinical and preclinical data suggests that solriamfetol, a novel dopamine and norepinephrine reuptake inhibitor, is a promising therapeutic option for excessive daytime sleepiness. We provide the first head-to-head comparison of in vivo efficacy between modafinil and solriamfetol in narcoleptic mice. Both compounds induced potent wake-promoting effects in littermate wild-type and orexin-tTA; TetO-DTA mice when dosed at active and resting phases. However, neither modafinil nor solriamfetol alleviated cataplexy. Remarkably, modafinil significantly induced locomotor activity but solriamfetol had small effects. Awake electroencephalogram profiles revealed that modafinil augmented theta oscillation in a dose-dependent manner, but, on the contrary, the response to solriamfetol was blunted, reflecting the differences in their neurochemical properties and anxiogenic effects. Drug-induced anxiety-related behaviors were evaluated at equipotent wake-promoting doses in WT and DTA mice using the elevated plus maze and forced swim tests. Importantly, 100 mg/kg of modafinil significantly produced anxiety-related behaviors in WT mice, whereas 150 mg/kg of solriamfetol did not have anxiogenic effects. On the other hand, DTA mice exhibited trait anxiety and altered drug responses. Our results suggest that solriamfetol potently promotes wakefulness without psychomotor effects and without inducing anxiety-related behaviors.

Strategies for Treatment of Disease-Associated Dementia Beyond Alzheimer's Disease: An Update

Memory, cognition, dementia, and neurodegeneration are complexly interlinked processes with various mechanistic pathways, leading to a range of clinical outcomes. They are strongly associated with pathological conditions like Alzheimer's disease, Parkinson's disease, schizophrenia, and stroke and are a growing concern for their timely diagnosis and management. Several cognitionenhancing interventions for management include non-pharmacological interventions like diet, exercise, and physical activity, while pharmacological interventions include medicinal agents, herbal agents, and nutritional supplements. This review critically analyzed and discussed the currently available agents under different drug development phases designed to target the molecular targets, including cholinergic receptor, glutamatergic system, GABAergic targets, glycine site, serotonergic targets, histamine receptors, etc. Understanding memory formation and pathways involved therein aids in opening the new gateways to treating cognitive disorders. However, clinical studies suggest that there is still a dearth of knowledge about the pathological mechanism involved in neurological conditions, making the dropouts of agents from the initial phases of the clinical trial. Hence, a better understanding of the disease biology, mode of drug action, and interlinked mechanistic pathways at a molecular level is required.

Effects of Modafinil (Provigil) on Memory and Learning in Experimental and Clinical Studies: From Molecular Mechanisms to Behaviour Molecular Mechanisms and Behavioural Effects

Modafinil (MOD, 2-diphenyl-methyl-sulphinil-2-acetamide) is a stimulant-like medicine used to treat narcolepsy. Off-label uses include improving cognitive ability in the course of other diseases. This review aims to discuss findings demonstrating the memory and learningenhancing activity of MOD in experimental and clinical studies. We included behavioral evaluations alongside the effects of MOD at the cellular and molecular level. MOD in different animal disease models exerted beneficial effects on induced memory and learning impairment, which in some cases were accompanied by modulation of neurotransmitter pathways or neuroplastic capabilities, reducing oxidative stress, or expression of synaptic proteins. Individuals treated with MOD showed improved memory and learning skills in different conditions. These effects were associated with regulating brain activity in some participants, confirmed by functional magnetic resonance imaging. Presented herein, data support the use of MOD in treating memory and learning deficits in various disease conditions.

Excessive rest time during active phase is reliably detected in a mouse model of myotonic dystrophy type 1 using home cage monitoring

Myotonic dystrophy type 1 (DM1) is a dominantly inherited neuromuscular disease caused by the abnormal expansion of CTG-repeats in the 3'-untranslated region of the Dystrophia Myotonica Protein Kinase (DMPK) gene, characterized by multisystemic symptoms including muscle weakness, myotonia, cardio-respiratory problems, hypersomnia, cognitive dysfunction and behavioral abnormalities. Sleep-related disturbances are among the most reported symptoms that negatively affect the quality of life of patients and that are present in early and adult-onset forms of the disease. DMSXL mice carry a mutated human DMPK transgene containing >1,000 CTGrepeats, modeling an early onset, severe form of DM1. They exhibit a pathologic neuromuscular phenotype and also synaptic dysfunction resulting in neurological and behavioral deficits similar to those observed in patients. Additionally, they are underweight with a very high mortality within the first month after birth presenting several welfare issues. To specifically explore sleep/rest-related behaviors of this frail DM1 mouse model we used an automated home cage-based system that allows 24/7 monitoring of their activity non-invasively. We tested male and female DMSXL mice and their wild-type (WT) littermates in Digital Ventilated Cages (DVCR) assessing activity and rest parameters on day and night for 5 weeks. We demonstrated that DMSXL mice show reduced activity and regularity disruption index (RDI), higher percentage of zero activity per each hour and longer periods of rest during the active phase compared to WT. This novel rest-related phenotype in DMSXL mice, assessed unobtrusively, could be valuable to further explore mechanisms and potential therapeutic interventions to alleviate the very common symptom of excessive daytime sleepiness in DM1 patients.

How hypocretin agonists may improve the quality of wake in narcolepsy

Excessive daytime sleepiness (EDS) is a complex symptom characterized by a strong urge to sleep during daytime accompanied by problems such as attention deficits, anxiety, and lower cognitive performance. The efficacy of treatments for EDS is determined by their ability to decrease sleepiness, and less attention has been given to the effects these compounds have on the quality of the wake itself. Hypocretin (HCRT; orexin) signalling is implicated in narcolepsy, and hypocretin receptor 2 (HCRTR2) agonists are in clinical trials for treating EDS in narcolepsy. Here, we review preclinical research to determine how HCRTR2 agonists may affect attention and anxiety compared with other EDS treatment strategies. We conclude that such compounds may improve not only the quantity but also the quality of wake, and we hope that they will create opportunities for more nuanced treatment strategies in narcolepsy.

A narrative review of treatment interventions to improve cognitive performance in schizophrenia, with an emphasis on at-risk and early course stages

Cognitive dysfunction is a core feature of schizophrenia (SCZ), which unfavorably affects SCZ patients' daily functioning and overall clinical outcome. An increasing body of evidence has shown that cognitive deficits are present not only at the beginning of the illness but also several years before the onset of psychosis. Nonetheless, the majority of treatment interventions targeting cognitive dysfunction in SCZ, using both pharmacological and nonpharmacological approaches, have focused on chronic patients rather than individuals at high risk or in the early stages of the disease. In this article, we provide a narrative review of cognitive interventions in SCZ patients, with a particular focus on pre-emptive interventions in at-risk/early course individuals when available. Furthermore, we discuss current challenges for these pre-emptive treatment interventions and provide some suggestions on how future work may ameliorate cognitive dysfunction in these individuals.