Search results for "stages"
showing 10 items of 217 documents
Physical activity, healthy behaviors and its motivational correlates: exploring the spillover effect through stages of change
2022
On the basis of the spillover or transfer effect and the transtheoretical model of change, this study assessed the association between amount of physical activity, healthy and unhealthy weight control behaviors, and motivational types, as well as their variability across stages of change. A total of 1219 randomly selected Mexican adults from 18 to 65 years old, representative of the city of Monterrey (México), participated in the study. Correlation analyses, differences by gender, and multivariate analyses of variance, controlling for age, were performed. We found that in the maintenance stage, there is higher frequency of physical activity more healthy weight control behaviors, as well as …
Plasticity of brain wave network interactions and evolution across physiologic states
2015
Neural plasticity transcends a range of spatio-temporal scales and serves as the basis of various brain activities and physiologic functions. At the microscopic level, it enables the emergence of brain waves with complex temporal dynamics. At the macroscopic level, presence and dominance of specific brain waves is associated with important brain functions. The role of neural plasticity at different levels in generating distinct brain rhythms and how brain rhythms communicate with each other across brain areas to generate physiologic states and functions remains not understood. Here we perform an empirical exploration of neural plasticity at the level of brain wave network interactions repre…
Subchronic Effects of Olanzapine on Sleep EEG in Schizophrenic Patients with Predominantly Negative Symptoms
2004
Background It is well known that sleep disturbance is an integral symptom of schizophrenia. In recent studies, a deficit of delta sleep has been observed in schizophrenic patients. Antipsychotic drugs with serotonin (5-HT2) receptor-antagonistic properties are considered to have delta sleep promoting effects. We have investigated the effects of subchronic olanzapine treatment on sleep EEG in schizophrenic patients. Methods The effects of administration of olanzapine (15 to 20 mg) on sleep were studied for four weeks in 10 male, drug-free patients suffering from schizophrenia with predominantly negative symptoms. Conventional sleep EEG parameters were investigated at baseline and after treat…
Diet and Neurodevelopmental Score in a Sample of One-Year-Old Children-A Cross-Sectional Study
2019
Environmental factors in the first years of life are crucial for a child&rsquo
Implementation Fidelity of a Program Designed to Promote Personal and Social Responsibility Through Physical Education
2011
The purpose of this qualitative comparative case study was to examine the implementation fidelity of a program designed to deliver the Teaching Personal and Social Responsibility (TPSR) model (Hellison, 2003) through physical education and its relationship with short-term outcomes for elementary school students. The research questions were: (a) was the program implemented with fidelity, and (b) did better fidelity yield better student outcomes. Thus, we conducted a study on the implementation process used by two teachers who delivered the same program in two physical education classes in two different elementary schools in Spain. Data sources included observations and interviews with teache…
Nonlinear EEG dynamics during sleep in depression and schizophrenia.
1994
The article deals with the question, whether nonlinear analysis of the sleep EEG may give clues to understanding of disturbed information processing in psychiatric diseases. We point out how the nonlinear approach to EEG dynamics is motivated and review recent investigations concerning nonlinear dynamical properties of physiological systems. We present calculations of the correlation dimension D2 and the principal Lyapunov-exponent lambda 1 for sleep EEG data from 9 depressive and 11 schizophrenic inpatients compared to healthy controls. Combining the findings for D2 and lambda 1 our results point to altered nonlinear brain dynamics mainly during slow wave sleep in depression and during REM…
Estimation of the dimensionality of sleep-EEG data in schizophrenics
1993
Deterministic chaos could be regarded as a healthy flexibility of the human brain necessary for correct neuronal operations. Several investigations have demonstrated that in healthy subjects the dimensionality of REM sleep is much higher than that of slow wave sleep (SWS). We investigated the sleep-EEG of schizophrenic patients with methods from nonlinear system theory in order to estimate the dynamic properties of CNS. We hypothesized that schizophrenics would reveal alterations of their dynamic EEG features indicating impaired information processing. In 11 schizophrenic patients, the EEG's dimensionality during sleep stages II and REM was reduced. We suggest that such lower dimensional ch…
An analysis of the brain's transfer properties in schizophrenia: Amplitude frequency characteristics and evoked potentials during sleep
1998
Background: Classical analysis of spontaneous sleep electroencephalogram (EEG) in schizophrenia commonly reveals alterations of sleep continuity, number of awakenings, slow-wave sleep (SWS), and REM sleep compared to healthy controls; however, conventional analysis cannot help understand dynamic differences of the sleep EEG during different sleep stages. Methods: We measured late components of auditory evoked potentials (AEPs) and visual evoked potentials (VEPs) during different sleep stages of 11 schizophrenic inpatients and in a sex- and age-matched control group from scalp positions FZ, CZ, and PZ. According to linear system theory, we then computed the amplitude-frequency characteristic…
Analysis of sleep EEG microstructure in subchronic paroxetine treatment of healthy subjects
1997
Paroxetine is a selective and potent serotonin reuptake inhibitor and its efficacy for the treatment of depression has been proven. Under acute and subchronical treatment regimens, disturbances of the regular sleep pattern are a reported side effect of the drug. The present study was therefore performed to investigate the impact of subchronic treatment with the selective serotonin reuptake inhibitor paroxetine on the microstructure of the sleep EEG. The study especially addressed the question of subchronic effects of paroxetine medication (30 mg/day) in eight healthy male volunteers in a double blind, placebo-controlled crossover design. Conventional sleep EEG parameters and a spectral powe…
Excitability and susceptibility of the brain's electrical activity during sleep: an analysis of late components of AEPs and VEPs.
1991
We investigated ten healthy male subjects and measured late components of AEPs and VEPs during sleep. According to Rechtschaffen and Kales (1968) we performed an off-line scoring procedure of sleep-EEG and averaged the AEPs and VEPs of five different periods, corresponding to sleep stages I, II, III, IV and REM. From the averaged evoked potentials we computed the amplitude-frequency-characteristic (AFC) of the brain (Basar, 1980) during different sleep stages. These AFCs characterize transfer properties of an oscillating system. A comparison of different AFCs has shown that the excitability of the brain depicts a clear alpha resonance during stage I, a pronounced delta resonance during stag…