Early life stressful events cause long-term neural changes that are associated with psychiatric disorders.

Early life manipulations focus on commonly the impact of remaining separate from the mother in a specific period of time. The maternal odor is required for pups to approach the mother for nursing. What happens when there is a mother that smell like a real mother but does not take care her own pups?

To investigate the fake mother effects on adult rat's behavioral changes, NMDR2B protein level changes in prefrontal cortex and hippocampus.

Wistar rats were used. Fake mother (n:13), early handling (n:12), maternal separation (n:14) and control (n:12) were the study groups. A fake mother is an object that smells like a real dam. When the real mother is separated from own pups fake mother stays with the pups for an hour. Manipulations were made during the postnatal first 14 days. Behavioral tests (social interaction test, elevated plus maze, novel object recognition test) were made between postnatal 62 and 78 days. NMDAR2B protein levels in prefrontal cortex and hippocampus were evaluated by using ELISA at postnatal 78 days.

In social interaction test, fake mother group exhibited less social behavior and more aggressive behavior than the other groups. Their long-term memory functions were the lowest. NMDAR2B protein levels in the hippocampus increased in rats that exposed to early stressful life events.

These results support that being raised by fake mother increases aggressive behavior and decrease social behavior in adulthood.

The authors have not supplied their declaration of competing interest.

Deficits in behavioral inhibition leading to impulsivity occur frequently in many otherwise different psychiatric diseases, mainly ADHD and borderline personality disorder (BPD). However, the research is complicated by using of different tests and their parameters. Further, the role of frontoparietal network in behavioral inhibition has been questioned recently.

The aims of our studies were:

– to present the influence of differences in inhibition tasks parameters;

– to describe neural correlates of behavioral inhibition in healthy people;

– to compare them with BPD and ADHD patients.

We implemented two different variants of Go/NoGo Task, one designed for behavioral research and the second for neuroimaging. Thirty healthy participants (37% of women, age range 15 to 33 years) underwent behavioral and fMRI measurement. Further, groups of patients with BPD, ADHD and their healthy controls underwent the Go/NoGo Task under both fMRI and EEG.

The results show differences in behavioral performance based on different task parameters. The fMRI results in healthy people show specific activation patterns within the frontoparietal network associated with inhibition trials (mainly inferior frontal gyrus, insula, cingulate gyrus, SMA, inferior parietal lobule). Further, we present differences between patients with BPD, ADHD and controls in BOLD signal and ERPs.

Go/NoGo Task design substantially influences the subjects’ behavioral performance. Our results with methodologically upgraded Go/NoGo Task design provide support for the inhibition frontoparietal brain network and its different activations in BPD and ADHD patients. The research was supported by Ministry of Health of the Czech Republic, grant nr. 15-30062A.

The authors have not supplied their declaration of competing interest.

Epilepsy is considered a complex neurological disorder with a great variety of clinical presentations that can resemble psychiatric disorders.

Disclose an unusual clinical case with psychiatric symptoms as the presentation of epilepsy.

Psychiatric assessments and retrospective review of the clinical file and literature research.

A 40-years-old Romanian woman presented to the psychiatry outpatient service with a history of persistent depressive mood and disturbed sleep for the past 3 years, complaining of a feeling that she described as “a snake squeezing around her body, starting in her left leg and spreading to the rest of her body up to the neck” associated with a sense of pins and needles, occurring during night time. She attended general practice, neurosurgery and psychiatry appointments. Her medical history included “gastritis” and lower left leg fracture and a pituitary microadenoma revealed in brain CT-scan. Blood work, including endocrine tests and brain-MRI were normal. Her symptoms initially led to diagnosis of: anxiety, somatization, Ekbom syndrome and depression. She was treated with antidepressives, antipsychotics and anxiolytics, without response. After careful reconstruction of the clinical history and further analyses of her complaints, the diagnosis of focal sensory jacksonian seizure was made. Levetiracetam introduction led to symptomatic remission.

Epilepsy includes a variety of neuropsychiatric symptoms. This case illustrates that epileptic patients may experience non-convulsive seizures that might be mistaken as primary psychiatric disorders. Neurologists and psychiatrists must be aware of this varied presentation while obtaining the medical history in order to investigate and manage this patient effectively.

The authors have not supplied their declaration of competing interest.

Syphilis is a sexually transmitted disease caused by Treponema pallidum. Early invasion of the central nervous system might occur early in the course of the disease. Clinical manifestations may include acute meningeal syphilis, meningovascular syphilis, paretic neurosyphilis and tabetic neurosyphilis. Psychiatric symptoms are often the presenting symptoms of this illness and the correct diagnosis involves both a high degree of suspicion and adequate diagnostic tests.

The authors report a case of a patient, with no previous history of mental illness, initially admitted in a psychiatric unit with a clinical picture suggestive of a mixed bipolar disorder episode who has been diagnosed with neurosyphilis a year after.

Review of clinical records and complementary exams.

By the first admission, the patient presented with depressed and irritable mood, emotional lability, aggressiveness, grandiose and racing thoughts. Upon discharge, he was diagnosed with bipolar disorder and referred to ambulatory unit. The following year he starts presenting cognitive deficits and a progressive loss of autonomy in daily living activities, being referred to neurology evaluation. A year after the first admission, he is admitted in a neurology unit and diagnosed with neurosyphilis.

Current prevalence of symptomatic neurosyphilis in Western Europe is unknown. Atypical cases presenting with heterogeneous psychiatric and neurologic symptoms, with no previous history of mental illness, should raise a high index of clinical suspicion, since consequences for the patient's health might be severe if not properly diagnosed and treated.

The authors have not supplied their declaration of competing interest.

Some previous findings indicate participation disturbance of balance between excitatory (GABA) and inhibitory (Glu) neurotransmitters in pathogenesis of schizophrenia. The aim of this study was to evaluate GABA and GLX levels in the brain of medicated UHR subjects.

Twenty-one (18–25 years, mean = 19.4, SD = 3.5) right-handed medicated UHR men and 26 (18–25 years, mean = 19.8, SD = 2.2) mentally healthy volunteers participated in this study. The patients were included in the UHR group in accordance with criteria of prodromal states.

1H MRS (MEGA-PRESS pulse sequence [Mescher, NMR Biomed 1998;11:266]) was used for GABA and GLX detection. Volumes of interest in size of 30 × 30 × 30 mm were placed in the left and right frontal lobes in the areas of the anterior cingulate cortex (ACC) (Fig. 1).

The main effects on the GABA/Cr (t[45] = 4.17, P < 0.01) (Fig. 2A) and GABA/GLX (t[45] = 2.84, P < 0.01) (Fig. 2B), were found in the left ACC (t[45] = 4.17, P < 0.01), with the patients having lower GABA/Cr and GABA/GLX ratios as compared to the control group. Also significant negative correlation (r = −0.49, P = 0.04) between GABA/Cr in the right ACC and the current daily dosage of antipsychotic medication in CPZ-Eq was found (Fig. 3).

This study reveals for the first time a significant reduction of (GABA) (25%) and GABA/GLX ratio (20%) in left AC of UHR subjects. According to (de la Fuente-Sandoval, Int J Neuropsychopharmacol 2015;19[3]) and association of (GABA) with daily dosage of medication found, this reduction may be caused by the antipsichotic treatment.

The authors have not supplied their declaration of competing interest.

Diffusion tensor imaging (DTI) is used frequently to explore white matter tract morphology and connectivity in psychiatric disorders. Connectivity alterations were previously reported for bipolar disorder, unipolar depression and schizophrenia. However, there is limited data on how these disorders differ from one another in terms of connectivity.

In this study, we aimed to explore connectivity differences between these disorders.

We analyzed DTI data of 37 patients with schizophrenia, 41 patients with bipolar disorder and 46 patients with unipolar depression. Group analyses were performed for schizophrenia versus bipolar and bipolar versus unipolar contrasts with using age as a covariate.

Threshold corrected results showed that connectivity at internal capsule and corpus callosum were most distinctive between groups. For corpus callosum (splenium), unipolar group showed the highest connectivity and schizophrenia group showed the lowest connectivity (Fig. 1). For internal capsule, schizophrenia group had the highest connectivity and unipolar group had the lowest connectivity (Fig. 2). Bipolar group had intermediate values for both tracts.

These results indicate that connectivity analysis may be helpful for differentiating psychiatric disorders.

The authors have not supplied their declaration of competing interest.

The knowledge on brain mechanisms of psychopathology can be very useful for the diagnosis and treatment of patients.

Patients with major depressive disorder (MDD) show attention bias to the negative emotional stimuli. Automatic (unconscious) emotional processing in such patients may become a prospective biomarker for depression.

We aimed at studying the EEG-correlates of unconscious expectation of angry human faces in MDD patients compared to healthy controls.

128-channel EEG was recorded in MDD (23 females and 7 males) and in healthy volunteers (22 females and 8 males) while they categorized pictures as humans or animals. Half of the pictures were neutral and half were showing the faces of angry humans or animals. The pictures were preceded by cues (one for each category), which meaning was not explained to the participants. We performed the wavelet analysis on EEG recorded during the face expectation period: 1000–2000 ms from the cue onset.

We found the emotional modulation (EM) in EEG rhythms during the expectation of angry vs. neutral faces in both groups. Statistical comparison of the spectral power using 2 × 2 factorial design showed that the EM differences (P < 0.05) between the groups were in the left parietal locations in 9 Hz and in 16–18 Hz, in the right parietal locations in 27–28 Hz, and in the right frontal area in 30–31 Hz.

The unconscious expectation of angry vs. neutral faces resulted in EM differences between the MDD and healthy controls in the right frontal and bilateral parietal areas mostly in beta and gamma ranges.

The authors have not supplied their declaration of competing interest.

Depression occurs frequently in patients suffering from Parkinson's disease (PD). However, the neural basis of depression in PD remains unclear. Diffusion magnetic resonance imaging (DMRI) connectometry is based on the spin distribution function (SDF), which quantifies the density of diffusing water.

The aim of this study was to assess the microstructural changes in the brain connectivity of PD patients with and without depressive symptoms.

DMRI was used to assess microstructural abnormalities in the brains of 16 PD patients with depressive symptoms compared to 11 PD patients without depressive symptoms. Data used in the preparation of this paper were obtained from the Parkinson's progression markers initiative (PPMI) database (http://www.ppmi-info.org/data/). This dataset was acquired on a 3-Tesla scanner (Siemens), producing 64 DWI at b = 1000 s/mm2 and one b0 image. Diffusion MRI data were corrected for subject motion, eddy current distortions, and susceptibility artefacts due to magnetic field inhomogeneity. DMRI connectometry was conducted in a total of 27 patients using percentage measurement.

PD Patients with depressive symptoms showed decreased anisotropy (FDR < 0.05) in the fornix bilaterally, left inferior longitudinal fasciculus (ILF) and corticospinal tract bilaterally compared to PD patients without depressive symptoms.

Lesser WM integrity of the left ILF fibers, which connect visual face recognition areas to the amygdala and hippocampus, seems to be associated with depressive symptoms in PD patients. Our study supports the hypothesis that neurodegenerative processes in projections from the somatosensory, cingulate, and insular cortices may be related to depression in PD.

The authors have not supplied their declaration of competing interest.

Psychopathy is characterized by superficial charm, untruthfulness, lack of remorse, antisocial behavior, egocentricity as well as poverty in major affective reactions. This clinical profile has been empirically conceptualized and validated. Recent brain imaging studies suggest abnormal brain activity underlying psychopathic behavior. However, no reliable pattern of altered neural activity has been disclosed so far.

To identify consistent changes of brain activity in psychopaths and to investigate whether these could explain known psychopathology.

First, we used activation likelihood estimation to meta-analyze brain activation changes in psychopaths across 28 functional magnetic resonance imaging studies reporting 753 foci from 155 analyses (P < 0.05, corrected). Second, we functionally characterized the ensuing regions employing meta-data of a large-scale neuroimaging database (P < 0.05, corrected).

Psychopathy was consistently associated with decreased brain activity in the right amygdala, the dorsomedial prefrontal cortex (DMPFC), and bilaterally in the lateral prefrontal cortex (LPFC). Consistently increased activity was observed bilaterally in the fronto-insular cortex (FIC) (Fig. 1). Moreover, we found that the physiological functional role of the candidate regions related to social cognition (DMFPC), cognitive speech and semantic processing (left FIC/LPFC), emotional and cognitive reward processing (right amygdala/FIC) as well as somesthesis and executive functions (RLPFC).

Psychopathy is characterized by abnormal brain activity of bilateral prefrontal cortices and the right amygdala, which mediate psychological functions known to be impaired in psychopaths. Hence, aberrant neural activity can account for pertinent psychopathology in psychopathy.

The authors have not supplied their declaration of competing interest.

The authors have not supplied their declaration of competing interest.

Chronic exposure to alcohol causes neuroadaptive changes in the brain, which leads to the recurrence of the disease. Promising in this area is to find new safe and effective pharmacological agents acting on molecular targets of influence of alcohol in the CNS.

Experiments were performed on male rats Wistar and male mice (CBAxC57Bl/6)F1.U. Experimental animals were formed alcohol dependence, based on long-term use of alcohol solution. Animals in a state of alcohol dependence were injected original anticonvulsant meta-chloro-benzhydryl-urea. We evaluated parameters orienting-exploratory behavior and emotional reactivity of the animals in the test “open field”, the cellular and humoral immune response. Properties of benzodiazepine receptors of the brain examined radioreceptor method using selective ligands [3H]flunitrazepam and [3H]Ro5-4864.

Chronic exposure to ethanol resulted in a significant change in the parameters of the experimental animal behavior and emotional reactivity in the test “open field”, observed suppression of immune response (∼40%), and increase in the number of receptors on 54.8–59.4% associated with reduced receptor affinity. Administration of meta-chloro-benzhydryl-urea led to the abandonment of the use of ethanol, recorded a correction of the above immunological and behavioral disorders due to alcohol intoxication. Properties of benzodiazepine receptors in the brain of experimental animals receiving the drug at a dose of 100 mg/kg for 14 days, indicators affinity and receptor density were close to the values in the control group.

Anticonvulsant has a modulating effect on the functional activity of the nervous and immune systems, reduces compulsive craving for alcohol.

The authors have not supplied their declaration of competing interest.

The authors have not supplied their declaration of competing interest.

The aim of the study was to analyze the microstructural and metabolic features of the corpus callosum in recently onset schizophrenia.

13 young (17–28 years old) male patients with recently onset schizophrenia (F20, ICD-10) and 15 sex and age matched mentally healthy subjects were examined.

3 T Philips Achieva scanner with 8-channel SENSE coil was used. DTI was conducted with EPI SENSE (TR = 9431 ms; TE = 70 ms). The values of diffusion coefficient (ADC), fractional anisotropy (FA), radial (RD) and parallel (PD) diffusivity were calculated using workstation Philips EBWS 2.6.3.4. Spectroscopic voxel (2 × 1 × 1 cm) was placed consequently in the corpus callosum genu and splenium. PRESS (TR/TE = 1500/40) was used.

In patients, increased ADC (P = 0.02) and RD (P = 0.008), decreased FA (P = 0.008) and NAA (P = 0.03) were found in the corpus callosum genu, No intergroup differences by PD, Cho, Cr, Glx were found in this area. Also, no statistically significant intergroup differences were observed for the DTI and MRS characteristics of the corpus callosum splenium.

It has been shown that RD increase is associated with demyelination process. So, an increase of RD in the present study could reflect demyelination in CC genu. Cells membranes abnormalities should lead to an increase of Cho which was not found. NAA reduction could be caused by reduction of axonal integrity. The latter process is considered to precede demyelination and not to be accompanied by PD rise. Thus, the present study revealed axonal integrity reduction and low demyelination in the genu of the corpus callosum in the early stages of schizophrenia.

The authors have not supplied their declaration of competing interest.

This study used proton magnetic resonance spectroscopy (1H MRS) to evaluate neurochemistry of the frontal cortex in adolescents with symptoms of sleep and depression.

19 non-medicated adolescent boys (mean age 16.0 y; n = 9 clinical cases with depression/sleep symptoms and n = 10 healthy controls) underwent 1H MRS at 3 T. MR spectra were acquired from the anterior cingulate cortex (ACC), the dorsolateral prefrontal cortex, and frontal white matter. Concentrations of N-acetyl aspartate, total creatine, choline-containing compounds, total glutamine plus glutamate, and myo-inositol (mI) were compared between the two subgroups and correlated with sleep and clinical measures in the total sample. Sleep was assessed with self-report questionnaires and ambulatory polysomnography recordings.

Concentrations of mI were lower in both frontal cortical regions among the depressed adolescents as compared to healthy controls. No statistically significant differences in other metabolite concentrations were observed between the subgroups. Frontal cortex mI concentrations correlated negatively with depression severity, subjective daytime sleepiness, insomnia symptoms, and the level of anxiety, and positively with total sleep time and overall psychosocial functioning. The correlations between mI in the ACC and total sleep time as well as daytime sleepiness remained statistically significant when depression severity was controlled in the analyses.

Lower frontal cortex mI may indicate a disturbed second messenger system. Frontal cortical mI may thus be linked to the pathophysiology of depression and concomitant sleep symptoms among maturing adolescents. Short sleep and daytime sleepiness may be associated with frontal cortex mI independently from depression.

The authors have not supplied their declaration of competing interest.

Depression is a common psychiatric disorder affecting many people globally, and the worst outcome is suicide. But its neurobiology is hardly understood.

To use DTI to characterize abnormalities of white matter (WM) integrity in major depressive disorder patients with suicide attempts or suicidal ideation.

Present study aimed to give a more complete profile for the association of cerebral WM abnormalities with suicidal behavior in major depressive disorder patients by quantifying the suicidal ideation and behavior severity.

Thirteen depressive patients with suicide attempts (SA), 14 depressive patients with suicidal ideation but no suicide attempts (SI), 13 depressive patients without suicidal ideation or suicide attempts (NSD) and 40 healthy controls (HC) received MRI scans on a 3 T magnet. Whole brain voxel-based analysis of FA based on DTI was performed among the four groups using a threshold of P < 0.05 with FWE correction. FA values were extracted by Marsbar software to quantify the changes.

The four groups had significant differences of FA in the in the left splenium of corpus callosum (peak Z = 5.36 at −14, −36, 22). Quantify comparison revealed that SA had significant decreased FA value than SI, NSD, and HC. There was no significant difference among the other three groups, although there was a trend that SI and NSD had lower FA values than HC in this region.

Depression and suicide are associated with microstructure abnormalities of the white matter and patients with suicide attempts may have severe cerebral alteration.

The authors have not supplied their declaration of competing interest.

Epilepsy is a frequent co-morbidity in patients with intellectual disabilities, some of whom require specialist services. The National institute for health and care excellence (NICE) has recommended that there should be equity of access to high quality of care regardless of the existence of a diagnosis of intellectual disability.

To observe current practice with regards to NICE guidelines for epilepsy care in patients with intellectual disability.

To identify the level of compliance with NICE guidelines and provide evidence which may inform care planning processes.

A retrospective review of the electronic and paper-based records of a total sample of intellectually disabled patients who accessed a specialist neuropsychiatry service for the management of epilepsy during a six-month period was carried out.

The records of 21 patients whose ages ranged from 20 to 58 years were audited. The waiting period ranged from 4 weeks to 46 weeks. There was evidence of Carer involvement in the management of 100% of the patients and seizure improvement since referral was documented in 66%. Non- medication treatment was offered in 67% of cases. Evidence of special considerations in view of patient's intellectual disability was recorded in 24%, best interest considerations in 24% and capacity assessment in 19%.

There is a significant improvement in the symptoms of 66% of patients in this audit. However there is room for improvement and a more specific plan for patients with intellectual disabilities should facilitate this.

The author has not supplied his/her declaration of competing interest.

Earlier considered a disorder affecting only children, today worldwide adult ADHD prevalence is estimated at 2.5%. The core symptoms; inattention, hyperactivity and impulsivity, often persevere impacting many fields of life.

To estimate the prevalence of ADHD symptoms in the general Finnish adult population.

We started with a population based and randomly drawn sample of 3000 adults, aged 18–44 years. When contacted, participants were provided three alternative ways to participate (online, letter, telephone interview). Using the adult ADHD rating scale (ASRS) screener all participants (n = 748) were categorized into groups: possibly symptomatic (≥4 points), controls (≤2 points) and undefined (3 points). Fifty-seven possibly symptomatic consented to further evaluation by a telephone interview, together with two age- and gender matched controls each.

Using the results from the ASRS screener, we calculated a 10.96% prevalence. Analysis of the complete ASRS resulted in a 5.08% and the recommended two-step evaluation in a 3.34% prevalence, out of whom two thirds considered being moderately or severely impaired by the symptoms.

This study suggests that a large number of adults in the general population are negatively affected by ADHD symptoms, almost all unrecognized by health care professionals. As ADHD is a burden for the patient, his family and the society, adult ADHD deserves greater attention in the future.

The authors have not supplied their declaration of competing interest.

European data on health-related quality of life (HRQoL) in adults with attention deficit/hyperactivity disorder (ADHD) in the general population is sparse.

To report HRQoL in UK adults with ADHD.

UK residents aged 18–55 years with a diagnosis of adult ADHD completed an online, cross-sectional survey including questions on disease history, the EuroQol Five Dimensions questionnaire with five-levels (EQ-5D-5L) and the Work productivity and activity impairment questionnaire: general health (WPAI:GH). ADHD symptom severity was assessed by telephone using ADHD rating scale version IV with adult prompts (ADHD-RS-IV).

The survey was completed by 233 participants (65.2% women; 77.3% white British), mean age 32.6 years (standard deviation [SD] 9.5), mean ADHD-RS-IV total score 43.46 (SD 7.88). Their mean EQ-5D-5L utility score of 0.74 (SD 0.21) was lower than the UK population norm of 0.86 (SD 0.23).[1] WPAI:GH scores indicated that health problems resulted in impairments of 32.04% in work productivity and 45.79% in regular daily activities. Regression analyses adjusting for gender, age and comorbidities demonstrated associations between EQ-5D-5L utility scores and gender (men had lower scores, P < 0.001), work impairment due to health problems (increasing impairment was associated with lower scores, P = 0.005) and age (for each additional year of age, scores decreased by 0.007, P = 0.010).

These results highlight the impact on health utility, work productivity and regular daily activities, and add to the description of the disease burden of adult ADHD in the UK.

This study was funded by Shire Development LLC.

Kings College London research support account for Asherson received honoraria for consultancy to Shire, Eli-Lilly and Novartis educational/research awards from Shire, Lilly, Novartis, Vifor Pharma, GW Pharma and QbTech speaker at sponsored events for Shire, Lilly and Novartis.

A significant number of people are not detained in hospital following assessment under the Mental Health Act 1983 (MHA) for possible detention. However, since amendments in 2007, some studies show an increase in total patient detentions. There is currently a lack of published research describing both outcomes and their affecting variables.

To determine rates, outcomes and affecting variables of MHA assessments in Norfolk, 2001–2011.

This observational study involved data collection from all 11,509 referrals for detention assessment under the MHA. Data was collected by Norfolk Social Services from 2001–2011 including age, gender and marital status.

Following assessment, 6903 (60.0%) were admitted; of those, 1157 (16.8%) were voluntary and 5746 (83.2%) were detained; 4606 (40%) were not admitted. Admission rates for males (50.4%) and females (49.5%) were similar. Detention rates increased with age: 37.6% of < 18s; 47.1% of 18–64s and 61.4% of 65+. A greater proportion of married (57.5%) and widowed patients (58.2%) were detained, compared with patients who were single (48%). Accommodation status showed 52% of those living with other were detained versus 43.9% of those with no fixed abode.

The finding that a higher proportion of married than single people, and of those living with others versus living alone, were detained following assessment is unexpected but significant and needs further investigation.

The authors have not supplied their declaration of competing interest.

It is widely reported that persons with major depressive disorder (MDD) show impaired performance on cognitive functioning, including frontotemporally mediated cognitive functions. The presence of cognitive dysfunction among patients with dissociative symptoms in trauma-related disorders may contribute to poorer treatment outcomes. Patients with major depressive disorder (MDD) frequently report dissociative symptoms. Here we investigate association of dissociative symptoms and neurocognitive dysfunction in patients with depression. We predicted that higher levels of dissociative symptoms among persons with MDD would be associated with lower scores on objective measures of frontotemporally mediated neurocognitive functions.

Patients who met DSM-V diagnostic criteria for a primary diagnosis of recurrent MDD were recruited. The Hamilton Rating Scale for Depression (HAM-D) was administered to assess the severity of depressive symptoms. To assess dissociative symptoms participants completed the Multiscale Dissociation Inventory (MDI). Two groups of patients were selected and matched. One group consisted of 13 patients having MDD and dissociative symptoms and second group consisted of 12 patients having MDD only. To measure frontotemporally mediated cognitive functioning following tests were administered: Color Trails Test; Wisconsin Card Sorting Test; Conners’ Continuous Performance Test (CPT). To examine group differences on clinical and neuropsychological scores, two-tailed independent samples t-tests was performed.

Group comparisons of performance on neuropsychological tests showed that participants with depression and dissociative symptoms performed worse on Color Trails Test Part 2 completion time, a measure of mental flexibility and processing speed. MDI depersonalization scores were correlated with measures of processing speed, mental flexibility and sustained attention. Specifically, Color Trails Test Part 2 scores were negatively correlated with depersonalization symptoms, where lower scores indicate slower completion time. Depersonalization symptoms on the MDI were also related to the CPT Hit Reaction Time Interstimulus Interval Change (a measure of vigilance), such that higher levels of depersonalization were related to better performance in a less active environment.

Our results suggest that dissociation is related to specific subtle impairments in neurocognitive functioning. Dissociative symptoms should ideally be assessed before treatment, as they may influence MDD treatment response. The findings point towards the need to further examine the impact of dissociation on functioning in patients with depression.

The authors have not supplied their declaration of competing interest.