The jet-lagged hamsters were worse at learning which of two chambers contained a desirable running wheel. Even after 28 days of a back-to-normal schedule, the formerly jet-lagged hamsters still showed learning and memory problems.
Full story in Wired.
I cannot find the original paper, and am mainly curious (1) why, and (2) whether the sample size is more than 10. If you know it, please put a link in the comments.
If true, this explains a lot about my life.
Hat tip to Nathanael at IPA.
3 Responses
Interesting statement for consideration. Here is some useful tips how to deal with the class discipline for beginning teachers: http://au.educationhq.com/news/38709/7-strategies-for-novice-teachers-to-maintain-classroom-discipline/ . Just newest approaches in teaching.
Not just hamsters!: http://www.jneurosci.org/cgi/content/abstract/20/6/RC66
It seems the cortisol levels play an important role here. For more on that, Sapolsky is a great read: http://www.amazon.com/Why-Zebras-Dont-Get-Ulcers/dp/0716732106
I was intrigued to find the original abstract myself after reading the wired article – not sure if this is what you wanted:
Poster 499. Circadian Physiology Location: Halls B-H Time: Monday, November 15, 2010, 1:00 pm – 5:00 pm Program#/Poster#: 499.5/JJJ3 Topic: E.08. Biological Rhythms and Sleep Support: NIH Grant HD-050470
The Hellman Award
Title: Repeated jet lag inhibits adult neurogenesis and produces long-term cognitive deficits in female hamsters
Authors: *E. M. GIBSON1, C. WANG2, S. TJHO2, N. KHATTAR2, L. J. KRIEGSFELD2; 1UC Berkeley, BERKELEY, CA; 2UC Berkeley, Berkeley, CA
Abstract: Frequent trans-meridian travel, chronic shift work, and poor sleep hygiene have become routine in society. Despite the deleterious impact on millions of individuals, few controlled studies have investigated the effects of circadian disturbances on psychological and physiological health. Retrospective and correlational studies indicate a strong link between shift work and a number of negative health consequences, including deficits in cognitive functioning. The present study investigated the impact of chronic temporal disruption and HPA axis activation on hippocampal cell proliferation, neurogenesis, and learning and memory. Syrian hamsters were exposed to a jet lag paradigm consisting of a 6-hr phase advance, every 3 days, for 25 days. Jet lag resulted in a striking decrease (>50%) in cell proliferation and neurogenesis. The impact of jet lag on cell proliferation was mediated through increased glucocorticoid concentrations, with adrenalectomy and basal corticosterone replacement abolishing this suppression. In contrast, the decrease in neurogenesis was independent of HPA axis activation, with equivalent deficits in neurogenesis in intact and adrenalectomized jet-lagged animals. Animals exhibited gross deficits in learning and memory during the jet lag that persisted one month after cessation of this treatment, indicating that the impact of these circadian insults may last well beyond the chronobiological challenge. Together, these findings underscore the importance of considering the health consequences for millions of individuals throughout the world engaging in shift work or flexible schedules, maintaining poor sleep hygiene, or flying repeatedly across time zones.
Disclosures: E.M. Gibson, None; C. Wang, None; S. Tjho, None; N. Khattar, None; L.J. Kriegsfeld, None.