Circadian regulation of sleep propensity, sleep structure and alertness: A symphony of paradoxes

1995 ◽  
Vol 7 (2) ◽  
pp. 24-26 ◽  
Author(s):  
D.J. Dijk

The adult human typically exhibits a monophasic sleep-wake cycle, i.e., remains awake and alert for approximately 16 hours and then sleeps for 8 hours. Recent experiments have provided new insights in the role of the endogenous circadian pacemaker in this consolidation of sleep and wakefulness.Sleep deprivation studies had shown previously that sleepiness and alertness are co-determined by a process which keeps track of the history of sleep and wakefulness and the circadian pacemaker, which keeps track of time. During every day life and during sleep deprivation both processes change simultaneously and their relative contribution to alertness and sleep propensity cannot be assessed under these conditions.

SLEEP ◽  
2015 ◽  
Vol 38 (3) ◽  
pp. 351-360 ◽  
Author(s):  
Julio Fernandez-Mendoza ◽  
Alexandros N. Vgontzas ◽  
Ilia Kritikou ◽  
Susan L. Calhoun ◽  
Duanping Liao ◽  
...  

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
James A. McCubbin ◽  
Hannah Peach ◽  
DeWayne D. Moore ◽  
June J. Pilcher

Hypertension has been linked to impaired cognitive/CNS function, and some of these changes may precede development of frank essential hypertension. The stress and fatigue of sleep deprivation may exacerbate these cognitive changes in young adults at risk. We hypothesize that individuals at risk for hypertension will show significant declines in cognitive function during a night of sleep deprivation. Fifty-one young adults were recruited for 28-hour total sleep deprivation studies. Hypertension risk was assessed by mildly elevated resting blood pressure and by family history of hypertension. A series of cognitive memory tasks was given at four test sessions across the sleep deprivation period. Although initially comparable in cognitive performance, persons at risk showed larger declines across the night for several indices of working memory, including code substitution, category, and order recall. These results suggest that cognitive/CNS changes may parallel or precede blood pressure dysregulation in the early stages of hypertension development. The role of CNS changes in the etiology of essential hypertension is discussed.


2018 ◽  
Vol 41 ◽  
Author(s):  
Kevin Arceneaux

AbstractIntuitions guide decision-making, and looking to the evolutionary history of humans illuminates why some behavioral responses are more intuitive than others. Yet a place remains for cognitive processes to second-guess intuitive responses – that is, to be reflective – and individual differences abound in automatic, intuitive processing as well.


2001 ◽  
Vol 120 (5) ◽  
pp. A442-A442
Author(s):  
P TSIBOURIS ◽  
M HENDRICKSE ◽  
P ISAACS

Crisis ◽  
2012 ◽  
Vol 33 (2) ◽  
pp. 80-86 ◽  
Author(s):  
Sami Hamdan ◽  
Nadine Melhem ◽  
Israel Orbach ◽  
Ilana Farbstein ◽  
Mohammad El-Haib ◽  
...  

Background: Relatively little is known about the role of protective factors in an Arab population in the presence of suicidal risk factors. Aims: To examine the role of protective factors in a subsample of in large Arab Kindred participants in the presence of suicidal risk factors. Methods: We assessed protective and risk factors in a sample of 64 participants (16 suicidal and 48 nonsuicidal) between 15 and 55 years of age, using a comprehensive structured psychiatric interview, the Composite International Diagnostic Interview (CIDI), self-reported depression, anxiety, hopelessness, impulsivity, hostility, and suicidal behavior in first-degree and second-relatives. We also used the Religiosity Questionnaire and suicide attitude (SUIATT) and multidimensional perceived support scale. Results: Suicidal as opposed to nonsuicidal participants were more likely to have a lifetime history of major depressive disorder (MDD) (68.8% vs. 22.9% χ2 = 11.17, p = .001), an anxiety disorder (87.5% vs. 22.9, χ2 = 21.02, p < .001), or posttraumatic stress disorder (PTSD) (25% vs. 0.0%, Fisher’s, p = .003). Individuals who are otherwise at high risk for suicidality have a much lower risk when they experience higher perceived social support (3.31 ± 1.36 vs. 4.96 ± 1.40, t = 4.10, df = 62, p < .001), and they have the view that suicide is somehow unacceptable (1.83 ± .10 vs. 1.89 ± .07, t = 2.76, df = 60, p = .008). Conclusions: Taken together with other studies, these data suggest that the augmentation of protective factors could play a very important role in the prevention of incidental and recurrent suicidal behavior in Arab populations, where suicidal behavior in increasing rapidly.


2020 ◽  
Author(s):  
B Mangiavillano ◽  
S Carrara ◽  
E Dabizzi ◽  
F Auriemma ◽  
V Cennamo ◽  
...  
Keyword(s):  

1997 ◽  
pp. 3-8
Author(s):  
Borys Lobovyk

An important problem of religious studies, the history of religion as a branch of knowledge is the periodization process of the development of religious phenomenon. It is precisely here, as in focus, that the question of the essence and meaning of the religious development of the human being of the world, the origin of beliefs and cult, the reasons for the changes in them, the place and role of religion in the social and spiritual process, etc., are converging.


Author(s):  
Dr. Manisha ◽  
Dr. Ruchi Jindal

Background: The term "ovarian cancer" includes several different types of cancer that  arise from cells of the ovary, most commonly, tumors arise from the epithelium or lining cells of the ovary.  Ovarian cancer risk is positively associated with higher consumption of dietary cholesterol and eggs, and inversely associated with a higher intake of vegetables. High consumption of fats may increase circulating estrogen levels, thus increasing the possibility of cell damage and proliferation that is responsible for cancerous growth. Material & Methods: The present study was conducted at Geetanjali Medical College and Hospital, Udaipur (Rajasthan). Total  100 cases (females) attending the obstetrics and gynecology department for some gynecological and other problem  were selected for this study between the age of 40-60 years, who were attending cancer centre at GEETANJALI MEDICAL COLLEGE AND  HOSPITAL, Udaipur (Rajasthan).                GROUP I: - It consisted of healthy females control subjects (n=50) .By routine examination and tests, we ensured that all the subjects were healthy and there were no signs and symptoms or history of ovarian tumor and diseases GROUP II: - It consisted of ovarian cancer females subjects (n=50) with a history of ovarian tumor. Results:   Higher level of cholesterol, LDL, VLDL and low level of HDL are found in ovarian cancer patients. Conclusion: The present study we highlights the importance and role of serum lipid profile in diagnosis, prognosis and recurrence of the disease. The study shows that serum level of cholesterol, LDL, VLDL was elevated in  patients of ovarian cancer while low level of HDL are found in ovarian cancer patients. Key words: lipid profile, ovarian cancer.


Sign in / Sign up

Export Citation Format

Share Document