Long-term increase in sensitivity to ketamine's behavioral effects in mice exposed to mild blast induced traumatic brain injury.

Neurobehavioral deficits emerge in nearly 50% of patients following a mild traumatic brain injury (TBI) and may persist for months. Ketamine is used frequently as an anesthetic/analgesic and for management of persistent psychiatric complications. Although ketamine may produce beneficial effects in patients with a history of TBI, differential sensitivity to its impairing effects could make the therapeutic use of ketamine in TBI patients unsafe. This series of studies examined male C57BL/6 J mice exposed to a mild single blast overpressure (mbTBI) for indications of altered sensitivity to ketamine at varying times after injury. Dystaxia (altered gait), diminished sensorimotor gating (reduced prepulse inhibition) and impaired working memory (step-down inhibitory avoidance) were examined in mbTBI and sham animals 15 min following intraperitoneal injections of saline or R,S-ketamine hydrochloride, from day 7-16 post injury and again from day 35-43 post injury. Behavioral performance in the forced swim test and sucrose preference test were evaluated on day 28 and day 74 post injury respectively, 24 h following drug administration. Dynamic gait stability was compromised in mbTBI mice on day 7 and 35 post injury and further exacerbated following ketamine administration. On day 14 and 42 post injury, prepulse inhibition was robustly decreased by mbTBI, which ketamine further reduced. Ketamine-associated memory impairment was apparent selectively in mbTBI animals 1 h, 24 h and day 28 post shock (tested on day 15/16/43 post injury). Ketamine selectively reduced immobility scores in the FST in mbTBI animals (day 28) and reversed mbTBI induced decreases in sucrose consumption (Day 74). These results demonstrate increased sensitivity to ketamine in mice when tested for extended periods after TBI. The results suggest that ketamine may be effective for treating neuropsychiatric complications that emerge after TBI but urge caution when used in clinical practice for enhanced sensitivity to its side effects in this patient population.

The Use of New Mobile and Gaming Technologies for the Assessment and Rehabilitation of People with Ataxia: a Systematic Review and Meta-analysis.

There are no currently available disease-modifying pharmacological treatments for most of the chronic hereditary ataxias; thus, effective rehabilitative strategies are crucial to help improve symptoms and therefore the quality of life. We propose to gather all available evidence on the use of video games, exergames, and apps for tablet and smartphone for the rehabilitation, diagnosis, and assessment of people with ataxias. Relevant literature published up to June 8, 2020, was retrieved searching the databases PubMed, ISI Web of Science, and the Cochrane Database. Data were extracted using a standardized form, and their methodological quality was assessed using RoB and QUADAS-2. Six studies of 434 retrieved articles met the predefined inclusion/exclusion criteria. Two of them were diagnostic, while 4 were experimental studies. Studies included participants ranging from 9 to 28 in trials and 70 to 248 in diagnostic studies. Although we found a small number of trials and of low methodological quality, all of them reported an improvement of motor outcomes and quality of life as measured by specific scales, including the SARA, BBS, DHI, and SF-36 scores. The main reason for such low quality in trials was that most of them were small and uncontrolled, thus non-randomized and unblinded. As video games, exergames, serious games, and apps were proven to be safe, feasible, and at least as effective as traditional rehabilitation, further and more high-quality studies should be carried out on the use of these promising technologies in people with different types of ataxia.

Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS): Pathophysiology and Clinical Implications.

The fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder seen in older premutation (55-200 CGG repeats) carriers of FMR1. The premutation has excessive levels of FMR1 mRNA that lead to toxicity and mitochondrial dysfunction. The clinical features usually begin in the 60 s with an action or intention tremor followed by cerebellar ataxia, although 20% have only ataxia. MRI features include brain atrophy and white matter disease, especially in the middle cerebellar peduncles, periventricular areas, and splenium of the corpus callosum. Neurocognitive problems include memory and executive function deficits, although 50% of males can develop dementia. Females can be less affected by FXTAS because of a second X chromosome that does not carry the premutation. Approximately 40% of males and 16% of female carriers develop FXTAS. Since the premutation can occur in less than 1 in 200 women and 1 in 400 men, the FXTAS diagnosis should be considered in patients that present with tremor, ataxia, parkinsonian symptoms, neuropathy, and psychiatric problems. If a family history of a fragile X mutation is known, then FMR1 DNA testing is essential in patients with these symptoms.

Isolated Insular Stroke: Clinical Presentation.

The symptoms related to insular ischemia have been the object of several studies in patients affected by stroke, although they are often accompanied by other ischemic alteration of adjacent brain structures supplied by the middle cerebral artery (MCA). The insula is vulnerable because of an ischemia due to thromboembolic vascular occlusion of the M1 MCA segment and the 2 main MCA branches (M2), mainly when they abruptly arise from the principal stem at a right angle. This topographical and anatomical peculiarity could enable an embolic formation, especially due to atrial fibrillation (AF), to occlude the transition pathway between M1 and M2, while the proximal origin of vascular supply protects the insula from ischemia due to hemodynamic factors. The aim of the study is to characterize the clinical aspects of acute ischemic strokes as a first event in the insular territory with specific attention to atypical manifestation. We have considered 233 patients with a first event stroke involving the insular territory and 13 cases of isolated insular stroke (IIS), from the stroke registry of the Policlinico "G.Martino", University of Messina, between the February 10, 2014 and the February 7, 2018. IIS patients showed CT/MRI lesions restricted to the insular region. Exclusion criteria were coexisting neurological diseases, structural brain lesions, extension to the subinsular area >50% of the total infarct volume. We identified 13 IIS patients (mean age 74 years), with an isolated symptom or a combination of typical and atypical aspects. Furthermore, we observed high frequency detection of cardiac disturbances. To our knowledge, just a few previous studies have described IIS; their incidence is still not well defined. IIS manifested with a combination of deficits including motor, somatosensory, speaking, coordination, autonomic and cognitive disturbances. After an ischemic stroke, AF manifestation could follow briefly the major event and its duration could be very short, as an autonomic dysfunction due to an insular infarction. This clinical condition requires a continuous cardiac monitoring for this dangerous occurrence.

The synergistic effect of poor motor coordination, gender and age on self-concept in children: A longitudinal analysis.

BACKGROUND: Self-concept is a critical psychosocial outcome in childhood that is shaped by many factors. Gender, motor coordination and age have been identified as three important contributors. AIM: The present study examined whether poor motor coordination (i.e., being classified as at risk for Developmental Coordination Disorder [rDCD]), gender and age have a synergistic effect on domains of self-concept and self-worth in children. METHODS: Data were derived from the Physical Health and Activity Study Team longitudinal open cohort project. Children enrolled in grade 4 (Mage = 9.88 ±â€¯0.35) at baseline (n = 1978) completed the Self-Perception Profile for Children 7 times over 4 years to evaluate their competence across multiple domains. The Bruininks-Oseretsky Test of Motor Proficiency - Short Form was completed once to evaluate children's motor coordination. Participants scoring ≤15th percentile were classified as rDCD. RESULTS: A significant 3-way interaction between rDCD, gender and age was observed for athletic ability, physical appearance and academic competence, but not social competence, behavioural conduct or global self-worth. Findings revealed developmental trajectories for self-perceptions of athletic ability, physical appearance, and academic competence were lowest among rDCD girls. Boys classified as rDCD also demonstrated lower athletic, academic and physical self-perceptions in comparison to typically developing children. CONCLUSIONS: Age intensifies disparities in self held athletic, physical and academic perceptions attributable to differences in gender and rDCD status, however, differences in these domains appear to be independent of children's overall views of themselves.

Screening of Some Novel 4, 5 Disubstituted 1, 2, 4-Triazole-3-thiones for Anticonvulsant Activity.

OBJECTIVE: In the present study, we synthesized fifteen 4, 5-disubstituted 1, 2, 4-triazol- 3-thione derivatives and evaluated for anticonvulsant activity with neurotoxicity determination. METHODS: The synthesized compounds were characterized using FTIR, 1H-NMR and MS. The molecular docking study was also performed to study the interactions of compounds with LYS329 residue of gamma amino butyric acid aminotransferase (GABA-AT) using Autodock 4.2 software. The anticonvulsant activity was assessed by maximal electroshock (MES) test and subcutaneous pentylenetetrazol (scPTZ) tests. The neurotoxicity was assessed by rotarod ataxia test. RESULTS: In MES test, compounds 5a, 8a and 9a were found active at 100 mg/kg and five compounds were found active at 300 mg/kg dose after 1 hr of administration. After 4 hr of drug administration, only two compounds 8a and 9a exhibited protection at 100 mg/kg. In scPTZ test, three compounds 2a, 6a and 8a were found active at 100 mg/kg and 7a was active at 300 mg/kg after 1 hr of test drug administration. Most of the compounds were found active in MES test with 8a and 9a being the most active among all. In docking study, 2a was found to be best compound based on the binding energy of -6.5 kcal/mol and estimated inhibition constant of 17.2 µM. CONCLUSION: Majority of synthesized compounds were found active in MES test, whereas only few were found to possess anti scPTZ activity. Among all compounds, only 14a caused motor coordination impairment in rotarod ataxia test at 300 mg/kg 1 hr duration.

Neuropsychiatric manifestations in celiac disease.

Celiac disease (CD) is a systemic, chronic immune-mediated disorder elicited by gluten and related prolamines in genetically susceptible subjects. Main manifestations of CD involve the digestive tract; however, a growing body of evidence supports the theory that symptoms may occur in every part of the body. It is known that some patients with CD can be asymptomatic, and additionally, the incidence of "nonclassical" CD with extraintestinal presentation is apparently increasing. We aimed to perform a thorough review of existing evidence for neurological manifestations of CD, providing an up-to-date description of prevalence and examining the pathogenetic mechanisms possibly involved. Neurological presentations are rare in children but as many as 36% of adult patients present with neurological findings. With severe malnutrition after progression of CD, different vitamin deficiencies may develop. Such problems can in turn overlap with previous neurological abnormalities including ataxia, epilepsy, neuropathy, dementia, and cognitive disorders. Here, the most prevalent clinical manifestations in adults and children have been discussed in further detail. Further research is needed to achieve a complete understanding of the nervous system involvement in CD, but clinicians should always remember that neurological and psychiatric symptoms might be part of the CD spectrum of manifestations.

Cerebellar Hypermetabolism in Alcohol Use Disorder: Compensatory Mechanism or Maladaptive Plasticity?

BACKGROUND: Despite severe structural brain abnormalities within the frontocerebellar circuit (FCC), cerebellar metabolism studied with 18 F-2-fluoro-deoxy-glucose-positron emission tomography (FDG-PET) is relatively preserved in patients with alcohol use disorder (AUD). The compensatory role of the cerebellum has been explored mainly through fMRI examination of AUD patients with the preserved level of performance. The present study aims at examining cerebellar metabolism and its relationship with regional brain metabolism and neuropsychological functioning in AUD patients. METHODS: Thirty-two recently detoxified AUD patients and 23 controls underwent an FDG-PET examination at rest. Participants also performed a neuropsychological battery assessing executive functions, verbal memory, and ataxia. RESULTS: Compared to controls, AUD patients had higher glucose uptake in the cerebellar lobule VIII, in association with hypometabolism, notably in several nodes of the FCC. Cerebellar hypermetabolism correlated negatively with regional hypometabolism in the premotor and frontal cortices. This pattern of regional hypermetabolism and hypometabolism related to ataxia and working memory deficits. CONCLUSIONS: These specific brain-behavior relationships do not fulfill the criteria for brain compensatory processes. Cerebellar hypermetabolism may rather reflect the involvement of different pathological mechanisms, leading to a maladaptive plasticity phenomenon within the FCC in AUD patients who are early in abstinence. Further studies are required to examine the contributions of structural and functional connectivity alterations in the cerebellar hypermetabolism and the changes in these pathological mechanisms with abstinence or relapse.

Central Nervous System Correlates of "Objective" Neuropathy in Alcohol Use Disorder.

BACKGROUND: Among the neurological consequences of alcoholism is peripheral neuropathy. Relative to human immunodeficiency virus (HIV) or diabetes-related neuropathies, neuropathy associated with alcohol use disorders (AUD) is understudied. In both the diabetes and HIV literature, emerging evidence supports a central nervous system (CNS) component to peripheral neuropathy. METHODS: In seeking a central substrate for AUD-related neuropathy, the current study was conducted in 154 individuals with AUD (43 women, age 21 to 74 years) and 99 healthy controls (41 women, age 21 to 77 years) and explored subjective symptoms (self-report) and objective signs (perception of vibration, deep tendon ankle reflex, position sense, 2-point discrimination) of neuropathy separately. In addition to regional brain volumes, risk factors for AUD-related neuropathy, including age, sex, total lifetime ethanol consumed, nutritional indices (i.e., thiamine, folate), and measures of liver integrity (i.e., γ-glutamyltransferase), were evaluated. RESULTS: The AUD group described more subjective symptoms of neuropathy and was more frequently impaired on bilateral perception of vibration. From 5 correlates, the number of AUD-related seizures was most significantly associated with subjective symptoms of neuropathy. There were 15 correlates of impaired perception of vibration among the AUD participants: Of these, age and volume of frontal precentral cortex were the most robust predictors. CONCLUSIONS: This study supports CNS involvement in objective signs of neuropathy in AUD.

Environmental enrichment restores the reduced expression of cerebellar synaptophysin and the motor coordination impairment in rats prenatally treated with betamethasone.

Preterm babies treated with synthetic glucocorticoids in utero exhibit behavioural alterations and disturbances in brain maturation during postnatal life. Accordingly, it has been shown in preclinical studies that SGC exposure at a clinical dose alters the presynaptic and postsynaptic structures and results in synaptic impairments. However, the precise mechanism by which SGC exposure impairs synaptic protein expression and its implications are not fully elucidated. Therefore, the purpose of this study was to investigate the effect of prenatal exposure to a clinical dose of betamethasone on the pre- and postsynaptic proteins expression in the developing rat cerebellum and prefrontal cortex, whose synchronized synaptic activity is crucial for motor control and learning. Consequently, the first objective of the present study was to determine whether prenatal betamethasone -equivalent to the clinically used dose- alters cerebellar vermal and cortical expression of synaptophysin, synaptotagmin I, post-synaptic density protein 95 and gephyrin - four important pre- and post-synaptic proteins, respectively- at a relevant adolescent stage. In addition, our second objective was to assess whether prenatal betamethasone administration induced coordination impairment using a rotarod test. On the other hand, it has been shown that the environmental enrichment is capable of improving synaptic transmission and recovering various behavioural impairments. Nevertheless, there is not enough information about the effect of this non-pharmacological preclinical approach on the regulation of this cerebellar and cortical synaptic proteins. Therefore, the third objective of this study was to examine whether environmental enrichment exposure could recover the possible molecular and behavioural impairments in the offspring at the same developmental stage. The principal data showed that adolescent rats prenatally treated with betamethasone exhibited underexpression of synaptophysin in the vermal cerebellum, but not change in levels of synaptotagmin I, post-synaptic density protein 95 and gephyrin. Analysis of the same pre- and post-synaptic proteins no showed differences in the frontal cortex of the same rats. These results were accompanied by an increase in the number of falls in the rotarod test, when the speed of rotation was fixed and when it was in acceleration, which means motor coordination impairments. Importantly, we found that environmental enrichment restores the betamethasone-induced reduction in the cerebellar synaptophysin together with a recover in the motor coordination impairments in prenatally betamethasone-exposed adolescent rats.

An mHealth App for Users with Dexterity Impairments: Accessibility Study.

BACKGROUND: A mobile health (mHealth) system called iMHere (interactive mobile health and rehabilitation) was developed to support individuals with chronic conditions and disability in their self-management regimens. The initial design of iMHere, however, lacked sufficient accessibility for users with a myriad of dexterity impairments. The accessibility of self-management apps is essential in ensuring usability. OBJECTIVE: This study aims to increase the usability of the iMHere system for users with dexterity impairments by increasing the app's accessibility. METHODS: We targeted the accessibility redesign by focusing on the physical presentation and the navigability of the iMHere apps. Six participants presenting with dexterity impairments were included in the usability study of the original and redesigned apps. RESULTS: We observed a lower number of touches needed to complete tasks (P=.09) and time to complete individual tasks (P=.06) with the redesigned app than with the original app; a significantly lower time for users to complete all tasks (P=.006); and a significantly lower error rate (P=.01) with the redesigned app than with the original app. In fact, no errors occurred with use of the redesigned app. Participant-reported overall average usability of the redesigned app (P=.007) and usability of individual modules (P<.001) were significantly higher than that of the original app due mostly to better ease of use and learnability, interface quality, and reliability. CONCLUSIONS: Improved usability was achieved using a redesigned app. This study offers insight into the importance of personalization in enhancing the accessibility and also identifies strategies for improving usability in app development.

An alcohol withdrawal test battery measuring multiple behavioral symptoms in mice.

Despite acceptance that risk for alcohol-use disorder (AUD) has a large genetic component, the identification of genes underlying various components of risk for AUD has been hampered in humans, in part by the heterogeneity of expression of the phenotype. One aspect of AUD is physical dependence. Alcohol withdrawal is a serious consequence of alcohol dependence with multiple symptoms, many of which are seen in multiple species, and can be experienced over a wide-ranging time course. In the present three studies, we developed a battery of withdrawal tests in mice, examining behavioral symptoms from multiple domains that could be measured over time. To permit eventual use of the battery in different strains of mice, we used male and female mice of a genetically heterogeneous stock developed from intercrossing eight inbred strains. Withdrawal symptoms were assessed using commonly used tests after administration of ethanol in vapor for 72 continuous hours. We found significant effects of ethanol withdrawal versus air-breathing controls on nearly all symptoms, spanning 4 days following ethanol vapor inhalation. Withdrawal produced hypothermia, greater neurohyperexcitability (seizures and tremor), anxiety-like behaviors using an apparatus (such as reduced transitions between light and dark compartments), anhedonia (reduced sucrose preference), Straub tail, backward walking, and reductions in activity; however, there were no changes in thermal pain sensitivity, hyper-reactivity to handling, or anxiety-like emergence behaviors in other apparatus. Using these data, we constructed a refined battery of withdrawal tests. Individual differences in severity of withdrawal among different tests were weakly correlated at best. This battery should be useful for identifying genetic influences on particular withdrawal behaviors, which should reflect the influences of different constellations of genes.

Open-Label Allopregnanolone Treatment of Men with Fragile X-Associated Tremor/Ataxia Syndrome.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting approximately 45% of male and 16% of female carriers of the FMR1 premutation over the age of 50 years. Currently, no effective treatment is available. We performed an open-label intervention study to assess whether allopregnanolone, a neurosteroid promoting regeneration and repair, can improve clinical symptoms, brain activity, and magnetic resonance imaging (MRI) measurements in patients with FXTAS. Six patients underwent weekly intravenous infusions of allopregnanolone (2-6 mg over 30 min) for 12 weeks. All patients completed baseline and follow-up studies, though MRI scans were not collected from 1 patient because of MRI contraindications. The MRI scans from previous visits, along with scans from 8 age-matched male controls, were also included to establish patients' baseline condition as a reference. Functional outcomes included quantitative measurements of tremor and ataxia and neuropsychological evaluations. Brain activity consisted of event-related potential N400 word repetition effect during a semantic memory processing task. Structural MRI outcomes comprised volumes of the hippocampus, amygdala, and fluid-attenuated inversion recovery hyperintensities, and microstructural integrity of the corpus callosum. The results of the study showed that allopregnanolone infusions were well tolerated in all subjects. Before treatment, the patients disclosed impairment in executive function, verbal fluency and learning, and progressive deterioration of all MRI measurements. After treatment, the patients demonstrated improvement in executive functioning, episodic memory and learning, and increased N400 repetition effect amplitude. Although MRI changes were not significant as a group, both improved and deteriorated MRI measurements occurred in individual patients in contrast to uniform deterioration before the treatment. Significant correlations between baseline MRI measurements and changes in neuropsychological test scores indicated the effects of allopregnanolone on improving executive function, learning, and memory for patients with relatively preserved hippocampus and corpus callosum, while reducing psychological symptoms for patients with small hippocampi and amygdalae. The findings show the promise of allopregnanolone in improving cognitive functioning in patients with FXTAS and in partially alleviating some aspects of neurodegeneration. Further studies are needed to verify the efficacy of allopregnanolone for treating FXTAS.

Rhythmic Interlimb Coordination Impairments and the Risk for Developing Mobility Limitations.

BACKGROUND: The identification of novel rehabilitative impairments that are risk factors for mobility limitations may improve their prevention and treatment among older adults. We tested the hypothesis that impaired rhythmic interlimb ankle and shoulder coordination are risk factors for subsequent mobility limitations among older adults. METHODS: We conducted a 1-year prospective cohort study of community-dwelling older adults (N = 99) aged 67 years and older who did not have mobility limitations (Short Physical Performance Battery score > 9) at baseline. Participants performed antiphase coordination of the right and left ankles or shoulders while paced by an auditory metronome. Using multivariable logistic regression, we determined odds ratios (ORs) for mobility limitations at 1-year follow-up as a function of coordination variability and asymmetry. RESULTS: After adjusting for age, sex, body mass index, Mini-Mental State Examination score, number of chronic conditions, and baseline Short Physical Performance Battery score, ORs were significant for developing mobility limitations based on a 1 SD difference in the variability of ankle (OR = 1.88; 95% confidence interval [CI]: 1.16-3.05) and shoulder (OR = 1.96; 95% CI: 1.17-3.29) coordination. ORs were significant for asymmetry of shoulder (OR = 2.11; 95% CI: 1.25-3.57), but not ankle (OR = 0.95; 95% CI: 0.59-1.55) coordination. Similar results were found in unadjusted analyses. CONCLUSIONS: The results support our hypothesis that impaired interlimb ankle and shoulder coordination are risk factors for the development of mobility limitations. Future work is needed to further examine the peripheral and central mechanisms underlying this relationship and to test whether enhancing coordination alters mobility limitations.

SPG7 and Impaired Emotional Communication.

The goal of this report is to describe the genetic mutations of a patient with cerebellar degeneration who had ataxia and impaired emotional communication that led to damage of family relationships. We extracted genomic DNA from peripheral blood lymphocytes and performed whole exome sequencing (WES) in this patient and his unaffected parents and siblings. Found mutations were confirmed by Sanger sequencing in each individual. We found compound heterozygous mutations in the paraplegin (SPG7) gene. One mutated allele has been previously described as a disease-causing missense mutation for spastic paraplegia type 7 (SPG7) (c.1529C > T, p.Ala510Val). The second mutated allele involved a single nucleotide deletion which results in a frameshift in the coding sequence (c.2271delG, p.Met757fs*65). The second allele is similar to, but unique from, other described, SPG7-linked truncation mutations. The abnormal emotional communication in this patient broadens the phenotypic boundary of SPG7.

Hashimoto's encephalopathy mimicking Creutzfeldt-Jakob disease.

Hashimoto's encephalopathy is a rare, imprecisely defined autoimmune neurologic syndrome associated with Hashimoto's thyroiditis that normally responds to corticosteroids. Here, we describe the case of a 55-year-old woman who presented with subacute cognitive decline and ataxia. Neoplastic, paraneoplastic, infectious, and metabolic etiologies were ruled out. Anti-TPO antibody level was markedly elevated at 966U/mL. After one month of 60mg/day of oral prednisone, she felt back to baseline and her Montreal Cognitive Assessment dramatically improved. Physicians should strongly consider this uncommon diagnosis in patients with rapid cognitive decline and no other clear etiology.

Clinically significant psychiatric symptoms among male carriers of the fragile X premutation, with and without FXTAS, and the mediating influence of executive functioning.

OBJECTIVES: To clarify the neuropsychiatric phenotype of fragile X-associated tremor/ataxia syndrome (FXTAS), and assess the extent to which it is mediated by the dysexecutive syndrome that is a major feature of the disorder. METHODS: We examined the prevalence of clinically meaningful psychiatric symptoms among male carriers of the fragile X premutation, with and without FXTAS, in comparison with men with a normal allele. Measures included the Neuropsychiatric Inventory (NPI), Symptom Checklist-90-R (SCL-90-R), and the Behavioral Dyscontrol Scale, a measure of executive functioning. Between-group differences were evaluated using logistic regression, followed by a mediation analysis with ordinary least squares regression to assess the contribution of dysexecutive syndrome to the observed psychiatric domains. RESULTS: Men with FXTAS showed higher rates of clinically significant symptoms overall and in specific domains: somatization, obsessive compulsive, depression, anxiety, psychoticism, agitation/aggression, apathy/indifference, irritability, and nighttime behavior problems. Post hoc analyses suggested that findings of psychoticism among men with FXTAS may be associated with participants' accurate acknowledgment of cognitive and physical dysfunction, rather than reflecting psychosis. Asymptomatic carriers showed no evidence of clinically significant psychiatric symptoms, but when all carriers were compared with men having a normal FMR1 allele, executive function deficits were found to mediate scores in several domains on both NPI and SCL-90-R. CONCLUSIONS: Building on prior research, the results provide evidence that the psychiatric phenotype for men includes clinically meaningful depression, hostility, and irritability, in association with behavioral and attentional disinhibition. It is likely that these problems reflect the effects of impaired executive functioning.