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Auditory steady-state responses (ASSRs) are widely applied to test brain ability to follow external stimulation and this appeared to be a promising method in neuropsychiatric disorders. Nevertheless, there is no established conclusion on the way aging affects phase-locking measures of ASSRs in healthy subjects. We aimed to identify the effects of aging on phaselocking measures of 40 Hz ASSR. The effect of aging was tested in a sample of 46 healthy male subjects (20-58 years old) during eyes open condition. Stimuli were 500 ms trains, consisting of 20 identical clicks (1.5 ms burst of white noise) delivered binaurally. Time-frequency analysis of the data was performed and phase-locking index, evoked amplitude and total intensity measures were extracted and decomposed by non-negative multi-way factorization. As shown by curve-fitting analyses, phase-locking index and evoked amplitudes were diminishing with age in the linear manner. This was also proven by ANOVA testing when sample was divided into age groups. No effect of age on the total intensity was found. The complexity of the factors modulating the 40 Hz ASSR is not entirely solved; nevertheless, the current results suggest that the ability to synchronize to high frequency external stimulation diminishes with age. This should be taken into account, particularly when ASSRs are used in clinical practice, comparing patients and healthy subjects.

The Paliperidone ER Treatment in Acute Intervention (PERTAIN) study was designed to explore treatment response, tolerability, and safety of flexible doses of paliperidone ER in patients with schizophrenia admitted for an acute exacerbation. This paper addresses a secondary analysis of PERTAIN data designed to explore predictors for treatment response, flexible dosing, and concomitant benzodiazepine use. This prospective, multicenter, phase 3b, open-label, single-arm, 6-week study used flexible doses of paliperidone ER (3 to 12mg once daily) to treat patients hospitalized for an acute exacerbation of schizophrenia, reflecting more closely daily clinical practice. Predictive models were evaluated for paliperidone ER flexible dosing, treatment response, and concomitant treatment with benzodiazepines as distinct independent variables. For the analysis of explanatory variables, a stepwise logistic regression was used, taking into account patient age, gender, body mass index, diagnosis and duration of schizophrenia, number of prior hospitalizations, psychotic symptoms (PANSS), disease severity (CGI-S), and patient functioning (PSP) at baseline. Early response (defined as response within 2weeks of treatment initiation) was also used as a predictor. Clinical response (defined as ≥30% decrease in PANSS total score and ≥1 point decrease in CGI-S from baseline to endpoint) was predicted by early clinical response (p

We aimed to evaluate the effect of changing attentional demands towards stimulation in healthy subjects on P50 potential-related high-frequency beta and gamma oscillatory responses, P50 and N100 peak amplitudes and their gating measures. There are no data showing effect of attention on P50 potential-related beta and gamma oscillatory responses and previous results of attention effects on P50 and N100 amplitudes and gating measures are inconclusive. Nevertheless the variation in the level of attention may be a source of variance in the recordings as well as it may provide additional information about the pathology under study. Nine healthy volunteers participated in the study. A standard paired stimuli auditory P50 potential paradigm was applied. Four stimulation conditions were selected: focused attention (stimuli pair counting), unfocused attention (sitting with open eyes), easy distraction (reading a magazine article), and difficult distraction (searching for Landolt rings with appropriate gap orientation). Time-frequency responses to both S1 and S2 were evaluated in slow beta (13-16 Hz, 45-175 ms window); fast beta (20-30 Hz, 45-105 ms window) and gamma (32-46 Hz, 45-65 ms window) ranges. P50 and N100 peak amplitudes in response to both S1 and S2 and their ratio were evaluated. The phase-locked P50 potential-associated gamma activity was attenuated during distraction tasks as compared to focused attention and an unfocused attention condition. The amplitudes and gating measures of P50 and N100 waves and beta activity were not sensitive to the competing distraction task performance. The use of a distraction task is not favorable when phase-locked gamma range activity is a key interest in auditory potential studies.

Introduction: This 52-week open-label extension (OLE) to a double-blind placebo-controlled recurrence prevention study examined the long-term safety and efficacy of flexibly-dosed paliperidone extended-release (ER) tablets in patients with schizophrenia.Methods: Patients entering the OLE either entered from the double-blind phase (placebo or paliperidone ER treatment) or entered directly from the run-in or stabilization phase (paliperidone ER) of the earlier study. During the OLE, patients were treated with flexibly-dosed paliperidone ER (3–15 mg/day; 9 mg starting dose). Safety and tolerability assessments included incidence of adverse events and extrapyramidal symptoms. Efficacy was also assessed.Results: The study population (n=235) was predominantly men (66%), 18–58 years of age. Twelve patients (5%) experienced an adverse event requiring treatment discontinuation. One or more serious treatment-emergent adverse events were reported in 13 patients (6%). There was one death. The mean Positive and Negative Syndrome Scale total score decreased from open-label baseline to endpoint for all groups, regardless of previous double-blind treatment (placebo or paliperidone ER).Conclusion: This year-long OLE provides information on the long-term safety and tolerability of paliperidone ER in patients with schizophrenia. The resulting safety and tolerability profile was similar to that seen in earlier short-term studies.

We evaluated the efficacy of paliperidone extended-release (ER), an investigational psychotropic agent, in delaying symptom recurrence in adult patients with schizophrenia and its safety and tolerability. In this randomized, double-blind, placebo-controlled, multicenter study, patients' symptoms were stabilized during an 8-week run-in and a 6-week stabilization phases using open-label, flexibly dosed paliperidone ER (3-15 mg once daily, starting dose = 9 mg). The primary efficacy variable was the time of first recurrence of schizophrenia symptoms, which included predefined changes in symptom scores, psychiatric hospitalization, self-injury, and suicidal or aggressive behavior during the double-blind phase (paliperidone ER or placebo treatment). Based on positive efficacy, the study was terminated at the preplanned interim analysis (43 recurrence events). The interim analysis (primary analysis) included 113 patients (mean age = 41 years; 51% men, 85% white). In the intent-to-treat group, 14 paliperidone ER-treated patients (25%) experienced a recurrence event versus 29 (53%) for placebo. Time-to-recurrence was significantly different, favoring the paliperidone ER group (P = 0.005, log-rank test): 25% quantile of time-to-recurrence was 83 days (paliperidone ER) versus 23 days (placebo). Final analyses (n = 205) were confirmatory. During initial open-label treatment with paliperidone ER, symptoms improved significantly. This improvement was maintained with continued treatment, as were functioning and quality-of-life measures. Treatment-emergent adverse events rates were similar: 35% for paliperidone ER and 40% for placebo. Paliperidone ER treatment versus placebo significantly delayed time-to-recurrence in patients with schizophrenia, maintained symptom stability and measures of functioning, and was generally well tolerated in this patient population.

Early effects of risperidone (2.5 +/- 1 mg/day) on auditory information processing were investigated in 9 neuroleptic naive patients with schizophrenia spectrum disorders and 9 healthy controls by using event-related potentials (ERPs). ERPs were elicited during active auditory "oddball" paradigm and were recorded before and after two weeks of treatment. Baseline P3 latencies were significantly delayed in patient group. Risperidone treatment did not change P3 amplitudes and latencies. However, P2 amplitudes were reduced in parallel with the clinical improvement measured by Positive and Negative Syndrome Scale (PANSS). Although risperidone did not change neural bases of active attention after two weeks of treatment, the reduction of P2 amplitude suggests that risperidone may affect auditory information processing in patients with schizophrenia spectrum disorders who never have been exposed to antipsychotic treatment.

ERPs could be helpful in the objectification of many psychological measures. In the last few decades one of the most commonly used ERPs has been the mismatch negativity (MMN) potential. It may be used to detect cognitive dysfunction in patients suffering from schizophrenia, dementia, depression, and can also be successfully applied in treatment monitoring. Nevertheless, changes of MMN parameters (prolongation of latency or reduction of amplitude) are not sufficiently specific to help to diagnose particular diseases. In this study we looked for more strict and specific MMN characteristics selective for schizophrenia. Fifteen healthy human subjects and twelve suffering from schizophrenia spectrum disorders were studied. Two new parameters were considered: the speed of ascending part of MMN slope (SAS) and the half area of the MMN wave. These two measures could differentiate the early stages of cognitive processing disturbances in schizophrenia spectrum disorders.