Thesis (M.Med.Sc.)--University of Hong Kong, 2004. / Also available in print.

Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed Oct. 31, 2007). Includes bibliographical references (p. 53-61).

Made available in DSpace on 2014-12-17T15:37:01Z (GMT). No. of bitstreams: 1 FranciscaPS_DISSERT.pdf: 2124364 bytes, checksum: fdbee75aadf5fa6b72cf6cdc5f8aa5a8 (MD5) Previous issue date: 2010-10-07 / The sleep patterns of students entering the university, is accompanied by many factors that can lead to changes in sleep habits, such as academic demands, new social opportunities, reduced parental care and irregular teaching schedules. The irregular pattern of sleep-wake cycle is usually accompanied by several daytime consequences, for example, reduced levels of motivation, performance, concentration, alertness and mood as well as increased fatigue and sleepiness.Thus, there are numerous reasons to support the fact that these students may suffer damage in their academic performance. The aim of this study was to evaluate the sleep-wake cycle (SWC) and cognition in medical students with different schemes teaching schedules. One group started classes at 08am, while the other started at 07am. We analyzed the data from 88 volunteers, 39 from each group. However, only those who participated in both stages of the study (n = 78) underwent cognitive testing. For subjective evaluation of the SWC was used questionnaires to check the quality of sleep, chronotype, daytime sleepiness and sleep habits. For objective evaluation was used actigraphy. For cognitive assessment was used the test MoCA (Montreal Cognitive Assessment). The results indicate that the group has class earlier had a greater irregularity of the SWC and a worse performance in cognitive testing. There was a difference between the schedules the week and weekend in the subjective variables, bedtime, wake up and sleep duration in both groups. The objective variables, time in bed showed difference between the schedules the week and weekend to the group started class at 08am and the variables bedtime, get up time, actual sleep time, time in bed and wake bouts in the class at 07am. In the cognitive test, there were differences between the groups in overall score and in the areas of executive function and memory recall. Thus, it is suggested that the class starting time may cause irregularity of the SWC and the irregularity may cause mild cognitive impairment. Moreover, cognitive testing MoCA was sensitive to detect differences among students, although the difference between the schedules is small / O padr?o de sono dos estudantes ao entrarem na universidade, ? acompanhado por muitos fatores que podem levar a mudan?as nos h?bitos de sono, tais como demanda acad?mica, novas oportunidades sociais, diminui??o do cuidado dos pais e hor?rios de aulas irregulares. O padr?o irregular de sono-vig?lia ? usualmente acompanhado por v?rias consequ?ncias diurnas, como diminui??o nos n?veis de motiva??o, desempenho, concentra??o, aten??o e humor, bem como aumento da fatiga e da sonol?ncia. Assim, existem in?meras raz?es para apoiar o fato de que, esses estudantes universit?rios, podem sofrer preju?zos em seu desempenho acad?mico. O objetivo desse estudo foi avaliar o padr?o ciclo sono-vig?lia (CSV) e a cogni??o em estudantes de medicina com diferentes esquemas de hor?rios de aulas. Uma turma iniciava as aulas ?s 08 horas da manh?, enquanto a outra iniciava ?s 07 horas. Para isso contamos com 88 volunt?rios. Por?m, desses, apenas os que participaram das duas etapas no estudo (n=78) realizaram o teste cognitivo. Para a avalia??o subjetiva do CSV foi utilizado question?rios para verificar a (1) qualidade de sono, (2) cronotipo, (3) sonol?ncia diurna e (4) h?bitos de sono. Para avalia??o objetiva foi utilizado o act?metro e para avalia??o cognitiva o teste MoCA (Montreal Cognitive Assessment). Os resultados indicam que a turma que tem aula mais cedo teve uma maior irregularidade do CSV e um pior desempenho no teste cognitivo. Houve diferen?a entre os hor?rios da semana e do fim de semana nas vari?veis subjetivas, hora de deitar, hora de levantar e dura??o do sono, em ambas as turmas. E nas vari?veis objetivas, tempo na cama na turma das 08h e, hora de dormir, hora de acordar, tempo real de sono, tempo na cama e despertares noturnos na turma das 07h. No teste cognitivo, houve diferen?a entre as turmas no escore geral e nos dom?nios de fun??o executiva e evoca??o de mem?ria. Assim, sugere-se que o hor?rio de in?cio das aulas pode provocar irregularidade do CSV e, essa irregularidade pode provocar um d?ficit cognitivo leve. Al?m disso, o teste cognitivo MoCA foi sens?vel para detectar diferen?as entre os estudantes, apesar da diferen?a entre os hor?rios ser pequena