By Gesa Junge, PhD
Now that Halloween and Thanksgiving are over, it seems that the world is moving full-speed towards Christmas. And while TV has Christmas adverts and Christmas specials, and the frequency of Christmas songs on the radio has been steadily increasing, what does Christmas look like in the world of scientific publishing? Interestingly, a Pubmed search for “Christmas”, has over a thousand results with “Christmas” in the title.
Some of these papers focus on holiday-related injuries, such as burns or falls. For example, one study analysed burn injuries due to Christmas decorations-associated fires, and while these are fairly rare, the majority of them actually occur after the holiday, presumably due to trees and wreaths drying out and becoming more flammable. Researchers in Calgary observed that several trauma patients were injured while installing Christmas lights, and this along with statistics showing increased risk of falls during winter months, prompted them to study this correlation. Most people in this study fell off of ladders or roofs, and most patients were male and middle-aged. The study also found that several patients sustained serious injuries, with 20% of patients requiring admission to the ICU and the median duration patients stayed in hospital being just over 2 weeks (15.6 days, range 2-165). This
Another study looked into blood alcohol content after consumption of commercially available (notably not homemade) Christmas pudding for lunch, measuring ethanol content of the pudding and then calculating what the blood alcohol content would be immediately after pudding consumption and 30 minutes later. The maximum blood alcohol content did not exceed 0.05g/dL and the authors conclude that “[h]ospital staff should feel confident that the enthusiastic consumption of Christmas pudding at work in the festive season is unlikely to affect their work performance […]”, as long as they ate less than 1kg of it.
There is also an interesting paper which addresses the question of how to win the Christmas cracker pull. This is a UK-based tradition, in which two people pull on opposite ends of a Christmas cracker until it splits into two uneven pieces, and the person who ends up holding the larger piece wins the usually completely useless plastic toy inside the cracker. The study distinguishes between three techniques: The QinetiQ strategy (two-handed pull, slightly downwards), the passive-aggressive strategy (two-handed grip, but letting the other person pull) and the control strategy (both sides pull approximately parallel to the floor). Turns out, the passive aggressive strategy is the one most likely to lead to a win (92% probability, 95% CI 0.76-1), at least with regards to Christmas crackers.
The results of the Christmas cracker and Christmas pudding studies are published in the same issue of the Medical Journal of Australia alongside a few other brilliant Christmas-related papers, one of which offers a diagnosis of “patient R”, suffering from a shiny lesion on his nose that severely affected his quality of life. The paper suggests lupus pernio may be the unifying diagnosis.
Finally, a group of researchers in Denmark set out to show that there is indeed such a thing as “the Christmas spririt”. This is not a well-defined state, but rather a generally joyful state brought about by decorations, food and smells associated with Christmas. The researchers showed people images with a Christmas theme (e.g. a street in the dark decorated with lights, or a plate of Christmas cookies decorated with a Santa figure and Christmas baubles) and similar images with nothing Christmas-associated (e.g. a regular street, or a plate of cookies on a kitchen counter with no decoration) while monitoring brain activity in a functional MRI scanner. They studied ten people who had celebrated Christmas from a young age (the Christmas group) and ten people who did not celebrate Christmas (the non-Christmas group). Both groups showed increased activity in the primary visual cortex when being shown Christmas-themed images compared to everyday images, but the Christmas group also showed greater activity in several brain regions that did not occur in the non-Christmas group, including the primary motor and premotor cortex, the right inferior/superior parietal lobule, and the bilateral primary somatosensory cortex. This suggests that people who have a strong association with Christmas traditions and celebrations respond differently to Christmas-themed images than people who have no association with Christmas. However, how exactly those brain areas bring about the mysterious Christmas spirit is not clear.
So in conclusion, please be safe when installing holiday lights and keep an eye on the candles, but do feel free to eat Christmas pudding while passive-aggressively pulling Christmas crackers, and if you still can’t seem to find the Christmas spirit, go get a functional MRI scan. Merry Christmas and Happy Holidays!