Are there differences in students' school success, biorhythm, and daytime sleepiness depending on their school starting times?

Chronotype is a characteristic of a person in a certain point of one's lifetime and it slowly changes with age. Adolescents start to go to bed later while schools impose early starting hours, which may become a problem for students who are unable to adapt their circadian rhythm. The aim of this study was to determine if differences in school starting times affect the students' chronotype, school success, or daytime sleepiness. We tested a total of 1020 students from four high schools in Osijek, Croatia. The students had alternating school shifts (school starting hours 7 AM or 13 PM and 8 AM or 14 PM, every other week, alternatively, respectively). The participants were tested using the Epworth Sleepiness Scale and the Morningness--Eveningness Questionnaire. Earlier chronotypes were characteristic of the students starting school earlier, but without significant difference in daytime sleepiness in comparison with those starting school later. Differences were also found between different age and gender groups, female and older students having earlier chronotypes. Students going to school earlier showed better school success than the latter. In conclusion, the study shows that students starting school earlier also have earlier chronotypes, which might be consequence of the adaptation to one hour earlier school starting time.

[Transsexuality: living in a wrong body?]. / Transseksualnost: zivot u krivom tijelu?

Transsexuality is a permanent feeling of uneasiness and non-affiliation to the gender in which a person was born, accompanied with a permanent striving to live and be accepted as a person of the opposite gender. The dysfunction appears in childhood and adult age. There is at least one transsexual male in 30,000 adult men and one transsexual female in 100,000 adult women. The aetiology of the dysfunction is still not elucidated, although there are hints connecting transsexuality with a non-standard hormonal activity in prenatal and short perinatal phase of development, which determines an erroneous sexual organization of the brain. Transsexuals differ with respect to biological gender and gender identity (male-to-female, female-to-male) as well as with respect to sexual orientation (homosexual and non-homosexual). For the majority of operated transsexuals the change of gender is a process which improves the quality of life and psychological health. Offering help to transsexuals is an exceptionally difficult task which demands cooperation of a mental health professional (psychiatrist, psychologist), endocrinologist and a surgeon.