The individual adjustment method of sleep spindle analysis: methodological improvements and roots in the fingerprint paradigm.

Evidence supports the robustness and stability of individual differences in non-rapid eye movement (NREM) sleep electroencephalogram (EEG) spectra with a special emphasis on the 9-16 Hz range corresponding to sleep spindle activity. These differences cast doubt on the universal validity of sleep spindle analysis methods based on strict amplitude and frequency criteria or a set of templates of natural spindles. We aim to improve sleep spindle analysis by the individual adjustments of frequency and amplitude criteria, the use of a minimum set of a priori knowledge, and by clear dissections of slow- and fast sleep spindles as well as to transcend the concept of visual inspection as being the ultimate test of the method's validity. We defined spindles as those segments of the NREM sleep EEG which contribute to the two peak regions within the 9-16 Hz EEG spectra. These segments behaved as slow- and fast sleep spindles in terms of topography and sleep cycle effects, while age correlated negatively with the occurrence of fast type events only. Automatic detections covered 92.9% of visual spindle detections (A&VD). More than half of the automatic detections (58.41%) were exclusively automatic detections (EADs). The spectra of EAD correlated significantly and positively with the spectra of A&VD as well as with the average (AVG) spectra. However, both EAD and A&VD had higher individual-specific spindle spectra than AVG had. Results suggest that the individual adjustment method (IAM) detects EEG segments possessing the individual-specific spindle spectra with higher sensitivity than visual scoring does.

Early experience with Suboxone maintenance therapy in Hungary.

BACKGROUND: Suboxone (Buprenorphine/naloxone) is a novel drug used in opiate substitution therapy. In Hungary, it was introduced in November 2007. Suboxone is a product for sublingual administration containing the partial mu-receptor agonist buprenorphine and antagonist naloxone in a 4:1 ratio. OBJECTIVE: Objectives of our study were to monitor and evaluate the effects of Suboxone treatment. METHOD: 6 outpatient centers participated in the study, 3 from Budapest and 3 from smaller cities in Hungary. At these centers, all patients entering Suboxone maintenance therapy between November 2007 and March 2008, altogether 80 persons (55 males, 35 females, mean age = 30.2 years, SD=5.48) were included in the study sample. During the 6-month period of treatment, data were collected 4 times; when entering treatment, 1 month, 3 months, and 6 months after entering treatment. Applied measures were the Addiction Severity Index, SCID-I, SCID-II, Hamilton Depression Scale, Hamilton Anxiety Scale, STAI-S State Anxiety Inventory, Beck Depression Inventory, Heroin Craving Questionnaire, WHO Well-being Inventory, Perceived Stress Scale, ADHD retrospective questionnaire, TCI short version, and Ways of Coping questionnaire. RESULTS: Nearly fourth of the altogether 80 heroin dependent patients (18 persons, 22.5%) dropped out of treatment during the first month (the majority, 12 persons [15%] during the first week) or chose methadone substitution instead. Following this period however, dropout rate decreased and the six-month treatment period was completed by 32 patients (40%). During the first month of treatment significant positive changes were experienced in all studied psychological and behavioral dimensions that proved to be stabile throughout the studied period. CONCLUSIONS: According to the early experience with Suboxone treatment, it is a well tolerable and successfully applicable drug in the substitution therapy of opiate addicts. A critical phase seems to be the first one or two weeks of treatment. Dropout rate is high during this early period, while after a successful conversion clients presumably remain in therapy for a long period. At the beginning of administration special emphasis must be put on informing patients, especially concerning withdrawal symptoms that might be present during the first week, which highly contributes to better retention in treatment.

The two-faceted nature of impulsivity in patients with borderline personality disorder and substance use disorder.

BACKGROUND: Impulsivity, which has been the subject of extensive debate in psychiatric research, is a clinically important concept, especially with respect to Borderline Personality Disorder (BPD) and Substance Use Disorders (SUD). The current study aims to examine the presence of two aspects of impulsivity (self-reported impulsivity and delay discounting) in patients with BPD, SUD (alcohol use=AUD or drug use=DUD) and the combination of both disorders (BPD+SUD). METHODS: Patients were recruited from eight different mental health treatment service facilities. A total of 345 participants were assessed and divided into six groups: (1) healthy controls (non-BPD, non-SUD), (2) patients with BPD (non-SUD), (3) DUD (non-BPD), (4) AUD (non-BPD), (5) BPD+AUD and (6) BPD+DUD. RESULTS: The behavioural measure of impulsivity is more conservative than the results of self-reported impulsivity. Furthermore, ANOVA indicated that BPD and SUD have significant effects on self-reported impulsivity, even when demographic variables, income, other psychiatric symptoms or depression are considered as covariates. On the other hand, the main effects of BPD and SUD are mediated by psychiatric symptoms and depression when delay discounting is considered as a dependent variable. CONCLUSIONS: When self-reported, impulsivity is over-estimated as compared to reports based on behavioural measures. These results provide support for the notion that impulsivity is not a unitary construct, and that it instead has different manifestations in BPD and SUD patients.

Prediction of general mental ability based on neural oscillation measures of sleep.

The usual assessment of general mental ability (or intelligence) is based on performance attained in reasoning and problem-solving tasks. Differences in general mental ability have been associated with event-related neural activity patterns of the wakeful working brain or physical, chemical and electrical brain features measured during wakeful resting conditions. Recent evidences suggest that specific sleep electroencephalogram oscillations are related to wakeful cognitive performances. Our aim is to reveal the relationship between non-rapid eye movement sleep-specific oscillations (the slow oscillation, delta activity, slow and fast sleep spindle density, the grouping of slow and fast sleep spindles) and general mental ability assessed by the Raven Progressive Matrices Test (RPMT). The grouping of fast sleep spindles by the cortical slow oscillation in the left frontopolar derivation (Fp1) as well as the density of fast sleep spindles over the right frontal area (Fp2, F4), correlated positively with general mental ability. Data from those selected electrodes that showed the high correlations with general mental ability explained almost 70% of interindividual variance in RPMT scores. Results suggest that individual differences in general mental ability are reflected in fast sleep spindle-related oscillatory activity measured over the frontal cortex.