Biomedical subjects

G Buela-Casal

Publications and source records attributed to G Buela-Casal.

9 recordsLinked to original sources

PubMed2003

The role of activation in the effect of total sleep deprivation on depressed mood.

The present investigation analyzes if the effect of Total Sleep Deprivation (TSD) on depressive mood in normal subjects is related to participants' activation levels. Reaction time (RT), subjective sleepiness, and depressive mood were assessed among 48 normal subjects who were subjected to 60 h of TSD. Subjects were divided into groups based on his/her depressive mood changes following TSD: subjects with worse response (n = 11), subjects with better response (n = 12), and intermediate group (n = 25). We sought to determine if RT and subjective sleepiness were related systematically to depressive mood changes following TSD. TSD produces a general reduction in activation (i.e., a monotonic increase in RT and subjective sleepiness) modulated by circadian oscillations. Baseline activation (RT) was confirmed partially as a predictor of participants' response to TSD. Subjects with high levels of activation (lower RTs at the baseline) experienced a better response (greater reductions in depressive mood) following TSD. There was no relationship between pre-treatment subjective sleepiness levels and the TSD effect on depressive mood. The results partially support the role of the activation level as a differential moderator of TSD effects on depressive mood in normal subjects.

Adolescent↗

PubMed2002

Electrodermal activity during total sleep deprivation and its relationship with other activation and performance measures.

The present study analyses the variations of the skin resistance level (SRL) during 48 h of total sleep deprivation (TSD) and its relationship to body temperature, self-informed sleepiness in the Stanford Sleepiness Scale (SSS), and reaction time (RT). All of the variables were evaluated every 2 h except for the SSS, which was evaluated every hour. A total of 30 healthy subjects (15 men and 15 women) from 18 to 24 years old participated in the experiment. Analyses of variance (ANOVAs) with TSD days and time-of-day as factors showed a substantial increase of SRL, SSS, and RT, and a decrease in body temperature marked by strong circadian oscillations. The interaction between day by time-of-day was only significant for RT. Furthermore, Pearson's correlations showed that the increase of SRL is associated to the decrease in temperature (mean r=-0.511), the increase of SSS (mean r=0.509), and the deterioration of RT (mean r=0.425). The results support previous TSD reports and demonstrate the sensitivity of SRL to TSD. The non-invasive character of SRL, its simplicity, and its relationships with other activation parameters, widely validated by previous literature, convert SRL into an interesting and useful measure in this field.

Adolescent↗

PubMed2001

Sleep pattern and daytime differences in the electromyographic activity and peripheral temperature.

For a long time, it has been said that most individuals sleep an average of 8 h. However, there are subjects that usually sleep less than 6 h (the ones placed under the label of short sleep pattern, SSP) and subjects that sleep more than 8 h (those classified by the long sleep pattern, LSP). Starting from this division, several studies have been carried out in order to establish possible differences in terms of psychological and physiological variables. This study is aimed at assessing the differences that might occur in electromyographic activity and temperature in long, medium and short sleep pattern subjects at two moments in the day. From a 300-subject sample, 17 long sleep pattern, nine medium sleep pattern and eight short sleep pattern subjects were selected. The physiological variables were assessed during a constant stimulation task in the morning (between 09.00 and 10.00 h) and in the evening (between 19.00 and 20.00 h). The inter-group analysis showed that the long sleep pattern and the short sleep pattern subjects differed in terms of electromyographic activity in the morning. This same analysis indicated that only long sleep pattern subjects showed changes in electromyographic activity over two measurements taken in the same day. The results point out that long sleep pattern subjects show more sensitivity towards changes, and that sensitivity is expressed in a different manner, depending on the time of the day.

Adult↗

PubMed2001

The effects of continuous positive air pressure treatment on anxiety and depression levels in apnea patients.

Various studies have focused on understanding how the continuous positive air pressure (CPAP) treatment improves the emotional state of obstructive sleep apnea patients, as well as factors that determine improvement. Yet the results are contradictory. The objective of the present study was to evaluate the changes in depression levels, anxiety state and anxiety trait levels of patients with obstructive sleep apnea after 1 month and again after 3 months of CPAP treatment. The sample consisted of 51 obstructive sleep apnea patients. The Beck Depression Inventory (BDI) standardized spanish version was used to assess depressive symptoms. The State-Trait Anxiety Inventory (STAI) was used to assess two elements of the response to anxiety: anxiety-state and anxiety-trait. The results indicate that there exist statistically significant differences in depression levels after 1 month and after 3 months of treatment (P < 0.05). In specific, a drop in depression symptomatology was observed in both experimental conditions. With respect to anxiety state-trait levels, the obtained results show statistically significant differences in anxiety-trait levels after 1 month and after 3 months of treatment (P < 0.05) and in anxiety state after 3 months of treatment (P < 0.01). Both variables experienced a decrease after CPAP treatment.

Adult↗

PubMed2001

[Situation of HIV/AIDS in Latin America at the end of XX century. Analysis of differences between countries].

The aim of this article is to analyze the current situation of AIDS in Latin American countries. Specifically, to compare their situation with other geographic areas of the planet, the prevalence index per countries, distribution per sex and age and, finally, the main ways of transmission in each country. The most recent data published by OMS and demographic data obtained from the Latin American and Caribbean Demographic Center (CELADE) was used. This analysis reflects that in Latin America it is impossible to talk about AIDS in a homogeneous way since the differences between countries are remarkable.

Acquired Immunodeficiency Syndrome↗

PubMed1997

The assessment of residual effects of a single dose of diazepam on visually-defined EEG patterns.

The aim of this single-blind study was to evaluate the residual effects of a 10-mg dose of diazepam on cortical activation 11 h after oral intake. The electroencephalographic segments (from O1-O2) delimited by a sequence of photic stimuli presented every 10 sec during a simple reaction-time task (36 min duration) were arbitrarily classified into nine cerebral patterns (EEGP). EEGP segment classifications were grouped into six peri-stimulus transitions expressed in percentages: alpha-blockade; alpha-persistence; beta-persistence; alpha-induction; activation and deactivation. A sample of 42 young healthy university students (21 females and 21 males) each underwent three counterbalanced experimental conditions (control, placebo and diazepam). Diazepam affected all the subjects, although the women showed a greater number of EEGP transitions which indicated deactivation, than did the men. The results show that this type of visual EEG analysis is a useful technique for detecting the residual effects of benzodiazepines.

Adult↗

PubMed1989

Normal human subjects with slow reaction times and larger time estimations after waking have diminished delta sleep.

A sample of 42 healthy young male human subjects was submitted to whole night polysomnography and attention performance tests upon awakening (simple visuomotor reaction time, RT, and time estimation, TE). In order to test whether performance is related to specific sleep parameters, the 15 fastest subjects (mean = 210 msec) and 15 slowest subjects (mean = 357 msec) in RT were compared in their TE and sleep parameters. Fast subjects were more precise in the estimation of 10 sec intervals (9.89; S.E. = 0.23 sec) than slow subjects (10.73; S.E. = 0.32). Slow subjects had significantly less delta sleep (mean = 73 min) than fast subjects (100 min, P less than 0.01) and otherwise similar sleep parameters. It can be suggested that attention after awakening is related to the amount of delta sleep in the night.

Adult↗

PubMedDate not supplied

[Comparative analysis of attributional style and self-esteem in a sample of depressed patients and normal control subjects].

INTRODUCTION: The present study assesses the role of attributions and self-esteem in depressive states. In depression, attributions can become central biased coping mechanisms that guide individual behavior. METHODS: Self-esteem and attribution bias was assessed in 40 depressed and 80 normal controls. RESULTS: Results of this investigation show that depressed patients made more internal attributions to negative events, and more external attributions for positive events than their normal counterparts, confirming an exaggerated attributional bias. CONCLUSIONS: The results suggest that depressed patients tend to blame themselves for their mistakes. Depressed patients made more stable and global attributions for negative events than for positive events, as opposed to what happens with the normal controls, making us believe that this bias will be maintained in time, and will eventually generalize to other life areas. This kind of study seems useful to develop efficient treatment programs and evaluation tools of depression.

Adult↗

PubMedDate not supplied

Analysis of convergent and discriminant validity of the Spanish experimental version of the State-Trait Depression Questionnaire (ST-DEP).

INTRODUCTION: This article reports data on the convergent and divergent validity of the Spanish adaptation of Spielberger's State-Trait Depression Questionnaire (ST-DEP). This questionnaire is a new tool because it offers an alternative to the obstacles found in most of the depression assessment scales that are differentiated in the content they evaluate and their estimation of depression levels. METHODOLOGY: The present study was carried out with a sample of 300 participants (103 males and 197 females), with mean age of 21.82 (2.74 s.d.) for males and 22.26 (3.66 s.d.) for females. All participants received information about the investigation and participated voluntarily. RESULTS AND CONCLUSIONS: The results indicate high and significant correlations of the Spanish ST-DEP scales with other depression measures (BDI, BDQ-R), thus showing the convergent validity of this questionnaire. Highly significant correlations between the Spanish ST-DEP and the State-Trait Anxiety Inventory (STAI) also appear, confirming that reported about the comorbidity between both disorders and the high scores in anxiety that subjects with depression have. In contrast, correlations with the State-Trait Anger Expression Inventory (STAXI-2) were low and non-significant in most cases, which demonstrated the divergent validity of the ST-DEP.

Adult↗