Biomedical subjects

Ling-Ling Tsai

Publications and source records attributed to Ling-Ling Tsai.

6 recordsLinked to original sources

PubMed2005

Sleep dependent effect of dark pulses on sleep in albino and pigmented rats.

Light-to-dark transitions have been found to enhance paradoxical sleep (PS) in albino rats but not pigmented rats. Furthermore, PS inducing effect of dark pulses in albino rats depends on sleep states. This study examined whether the relationship between PS and preceding non-rapid-eye-movement sleep (NREMS) in pigmented Brown Norway rats was different from that in albino F344 rats and whether such a difference was associated with different responses to dark pulses in the two rat strains. Both rat strains showed a positive relationship between PS and preceding NREMS. However, only the albino F344 rats exhibited the PS inducing effect of dark pulses. Dark pulses did not alter the relationship between PS and preceding NREMS in either rat strain, and, reciprocally, nor did duration of preceding NREMS affect dark pulse-induced PS enhancement. Furthermore, this study verified that dark pulses given during NREMS in albino F344 rats specifically induced the suppression of NREMS concomitant with the enhancement of PS. This study proposed that dark pulses might inhibit NREMS and facilitate PS regulating areas concurrently in albino rats.

Animals↗

PubMed2005

Repeated light-dark shifts speed up body weight gain in male F344 rats.

This study is aimed at verifying the causal relationship of chronic circadian desynchronization and changes in body weight control. Eight male albino F344 rats aged between 12-15 wk were subjected to twice weekly 12-h shifts of the daily light-dark (LD) cycle for 13 wk (3 mo). Continuous circadian phase shifts consisting of intermittent phase delay and advance and reduced circadian amplitudes were consistently displayed in all five experimental rats implanted intraperitoneally with heart rate, body temperature, and activity transponders. The experimental rat maintained a greater body weight during LD shifts and even after 10 days of recovery than that of the age-matched control rat, which was maintained on a regular LD cycle. Body weight gain was greater in the first 2 mo of LD shifts in the experimental rat than in the control rat. Relative to the baseline, food intake and activity percentages were increased and reduced, respectively, for the experimental rats. Features of these results, such as increased body weight gain and food intake, and reduced activity, suggest a causal relationship of chronic circadian desynchronization and changes in body weight control in male albino F344 rats.

Analysis of Variance↗

PubMed2005

Impairment of error monitoring following sleep deprivation.

STUDY OBJECTIVES: To verify if error monitoring, involving detection and remedial actions, is affected by sleep deprivation. DESIGN: Event-related brain potentials (ERPs) and electroencephalogram spectrum during performance of Flanker task were obtained in a within-subject, counter-balanced, repeated-measures design. SETTING: Sleep deprivation and data collection were conducted in a laboratory setting. PARTICIPANTS: Sixteen young healthy adults (7 women, 18-23 years old) INTERVENTIONS: Performance and electroencephalogram data were collected after normal sleep and sleep deprivation. MEASUREMENTS AND RESULTS: Compared to normal sleep, 1 night of sleep deprivation resulted in slower and more varied reaction times, more response errors and omissions, and impaired posterror adjustments to response accuracy. Concomitantly, 2 error-related ERPs, error-related negativity and Pe, showed reduced amplitude measurements after sleep deprivation. Conversely, conflict monitoring as expressed behaviorally and by the N2 component of the ERP was not attenuated by sleep deprivation. Ten of the sixteen participants maintained similar accuracy levels under both sleep conditions, although they still showed reduced error-related negativity and error positivity amplitude measurements and impaired error remedial actions for accuracy. Electroencephalogram spectral activity at beta and theta frequency bands was related to response correctness on subsequent trials but not related to that of preceding trials under both sleep conditions. CONCLUSIONS: One night of sleep deprivation impaired both the error detection and error remedial actions and highlighted the inability to avoid making errors again after erroneous responses were already made. The results showed that a vicious cycle occurred between performance deterioration and impairment of error-remedial mechanisms that inevitably led to making more successive errors.

Adolescent↗

PubMed2004

Sleep patterns in college students: gender and grade differences.

OBJECTIVE: Since gender effect is inconsistent and grade effect has not been addressed in previous studies, we investigated both effects on the daily sleep patterns in a group of young college students. METHODS: The sample consisted of 237 students aged 18-24 years. Each subject completed a 7-day sleep log. RESULTS: Gender differences were found in several sleep variables and those were mostly not dependent on weekday/weekend difference. The female students went to bed and rose earlier and had longer sleep latency, more awakenings, and poorer sleep quality than the male. Gender differences were also shown in the relationship between sleep quality and other sleep variables. The correlation between sleep quality and rise time, time in bed, and sleep efficiency was stronger in men than in women. In contrast, grade differences were mostly dependent on weekday/weekend difference. The freshmen rose earlier and had shorter sleep time than did the other students on weekdays only. Sleep latency was the longest in seniors on weekdays only. CONCLUSION: This study showed that gender differences in sleep patterns and sleep difficulties were remarkable in the group of young college students. Alarmed by the high prevalence of sleep difficulties among general college students, it is recommended that the students should be informed of their sleep problems and the consequences.

Adolescent↗

PubMed2004

Sleep education in college: a preliminary study.

In this study we evaluated the effect of a two-credit (100 min./week) "Sleep Management" course on the sleep patterns of college students as the course progressed over an 18-wk. semester. Curricular activity included lectures, group discussions, and practice of self-evaluation of sleep. Instead of giving the students the whole list of sleep hygiene at the outset of the course, each concept of sleep hygiene was introduced and discussed under related lecture topics. A total of 241 students (131 men and 110 women) took the course and kept 7-day sleep logs three times. Concurrently, sleep-log data were collected from 65 students (32 men and 33 women) who were not taking the course. Both groups showed similar varieties of academic backgrounds and characteristics of sleep patterns at the beginning. Similarly, their sleep patterns, namely, rise time, nighttime awakenings, time asleep, time in bed, sleep efficiency, and rise time regularity, changed over the semester. Women in both groups had more nighttime awakenings. In contrast, sleep quality was progressively better for the group in the course but not for the control group. Only women in the course decreased their nap time in the second and third months. Thus, the course of "Sleep Management" only had a mild and limited effect on sleep patterns. The course content needs refinement to maximize influence on students' sleep patterns and habits, particularly, on reduction of insufficient sleep and daytime sleepiness which are the highest ranking sleep problems among college students.

Adult↗

PubMed2002

Enhancement of paradoxical sleep by lights-off stimulation depends on sleep states.

This study was aimed at clarifying whether the lights-off stimulation effect on paradoxical sleep (PS) enhancement in albino rats depends on sleep and wakefulness states. Male Sprague-Dawley rat pairs were subjected to lights-off stimulation for 320 s when one of the two rats was in non-rapid-eye movement sleep (NREM) continuously for at least 64 s (NREM-off condition). Simultaneously, the other rat received the same lights-off stimulation during any sleep and wakefulness state (random-off condition). Each rat underwent both lights-off conditions. The sequence of the two lights-off conditions was counter-balanced. PS was enhanced during the lights-off period in both the NREM-off and random-off conditions. However, the increased amount of PS was greater in the NREM-off condition than the random-off condition. In the random-off condition, rats had more PS in the lights-off period than in the preceding and succeeding lights-on periods only if they were in high EEG amplitude NREM (HS) at lights-off. Thus, this study verified that the lights-off stimulation effect on PS enhancement in the albino rat depended on the sleep states. However, the lights-off treatment did not alter the relationship between PS and preceding NREM, or the hippocampal theta activity or the PS latency in the lights-off period.

Animals↗