What is it about women at night…?

What is it about the female species during the later hours of the night…? As I sit in the library and study for my upcoming research methods test tomorrow (pray for me ), I can’t help but notice the number of women who are loudly laughing at each other (seriously, it’s distracting). I am talking “fall out of your seat” laughter at situations that seem to be only mildly humorous. Observing this behavior triggers memories of my previous girlfriend’s or female friends, even female family members engaging in similar comical behavior after the sun had gone down and the darkness had crept around us. And so I ask you in all sincerity, are the majority of women susceptible to increased perceptions of comical episodes resulting in larger amounts of laughter during later hours of the evening or night? Alice Eagly mentioned in her in her book “Sex Differences in Social Behavior: A Social-Role Interpretation” (1987) that “in social situations women smile and laugh more than men”. The research seems to agree with such a statement (Hall, 1984), but why? Perhaps examining the research with greater scrutiny will give us an indication. A study conducted at the Stanford University of Medicine ran physiological tests on one group of men and one group of women (10 subjects each) to examine the way that a person's brain responds to humor. They did this by exposing subjects to comical stimuli). The study found that the women were more likely than their male peers to use the part of the brain that processes rewards during exposure. Further analysis of the data seemed to suggest that women had lower expectations in regard to a reward (in this case, the reward being the punch-line of the joke or cartoon), which resulted in them enjoying the experience more than the men (visit the address http://www.helium.com/tm/395919/several-recent-studies-suggested for further exploration). Could it be that the expectations in regard to a reward in females decrease at night?
Of course this is simply one study with one possible interpretation to why women laugh more than men, so it’s quite difficult to draw causality, especially if a study is still vulnerable to research biases. What if things are not funnier, but that women are simply less hindered in expressing emotions when tired? Research does support the idea that women are more emotionally expressive than men (Brody & Hall, 1993; Broverman et al., 1972; Zuckerman & Larrance, 1979). Perhaps circadian rythem is tied to emotionally expression, and more noticable in the more vunerable?
I recognize that proposing a valid hypothesis about such a statement in only an hour’s review of the vast research available on female and male nonverbal & verbal communication is impossibility. It is futile and a obvious and unfortunatly overly successful time consuming distraction. It is now 1:20 in the morning and I have a test to study for. Seriously, I can’t believe I spent a hour and a half writing/researching this when I have a very hard test tommarow morning…what the %#@$! is wrong with me?!? (sigh) goodnight…(and pray for me)

By the way, If such seemingly futile questions appeal to you, check out Sex Roles: A Journal of Research published Jan, 1995 by Nancy Briton and Judith A. Hall. The article can be found at http://findarticles.com/p/articles/mi_m2294/is_n1-2_v32/ai_17012184 .