New Research Links Sleep Drugs To Improved Memory
March 13, 2013 2:24 p.m.
University of California, Riverside Psychologist Sara Mednick
Related Story: New Research Links Sleep Drugs To Improved Memory
CAVANAUGH: We will speak about seasonal sleepiness with a sleep researcher. It's 12:21 and you're listening to KPBS Midday Edition. Many people look forward to daylight savings time but the feeling comes with a price which many of us are paying today, losing an hour over the weekend and messing up your sleep cycle and since almost half of Americans report not getting enough good sleep normally the days after daylight saving can be rough. Here to talk about the effects of the time change is my guest, UC Riverside psychologist Sara Mednick, she's a sleep researcher and lead author of a study on sleep aids in memory. Sara, welcome to the program.
MEDNICK: Thank you very much
CAVANAUGH: I think there are more traffic accidents, even more heart attacks after the switch to daylight savings time, what are the most common effects of people experience?
MEDNICK: Tiredness. Just being very tired. I was talking to a friend of mine who is a teacher at Mesa College and he's got a big class and intro math class which usually have 100 students then there were six students there this morning so it's a very hard transition to make to suddenly lose an hour of sleep especially for younger people who really actually need the morning sleep more than people who are a little bit older. So, tiredness and missing class, coming late to work, but then there are the traffic accidents, increase in heart attacks, increasing suicide and the increase in swing we lose daylight savings so it really does affect us on a long-term basis. So it is a surprising small effect even though you say okay, it is 40 minutes.
CAVANAUGH: I was going to say why does losing the one little hour, why does it have such a big impact, do we know?
MEDNICK: Well one of the biggest reasons is we have what are called circadian rhythms which is the internal clock that guides us forward the best activity should be and when we are mostly B's that tells us what we should be active and non-active and then there's the rest of the world that tells us what we should be active or not and there's an idea of social jet lag which is that our internal clock is not aligned with the social clock. You know, having to get to work and be at school and take care of the kids and you know, late working nights and that cost between what our internal rhythm is in the external social rhythm is really the thing that actually seems to be related to not only feeling bad after not having enough sleep, but there's a recent study last year by a group, lead author Ronan Burke which says that increasing the social jet lag was correlated with increases in obesity. So there seems to be a wide range of increased importance to not only sleep time but the period of sleep that you are slipping.
CAVANAUGH: Daylight savings was in use on and off of the last century and became a permanent fixture in the US since the 1960s, but back then not much was really understood about the possible effects on sleep patterns, was there?
MEDNICK: Sleep research is a new field and an exciting field to be in because at this point we know so little about it and every time someone asks me a question I think that's an interesting idea, we have no idea about this. There so many questions you can ask about sleep which makes it interesting as a researcher, but not so great as somebody out there who is really being affected by this because we still have not adapted our social norms to be helpful for people with different type of sleep phases.
CAVANAUGH: What is the actual, I mean, is there a real pattern we should be on his basically up at dawn and asleep at sunset?
SARA MEDNICK: It varies by who you are, there's a wide individual difference, some people are late phase especially people who are adolescents, through adolescence actually need to go to bed later and later and sleep later and later. So they are the ones who are most at risk for all the problems we are talking about because they have to wake up even earlier than I normally do and then waking up early is painful enough that waking up an hour earlier than that is more painful also adolescents usually are more delete and they need to be a week later and wake up later whereas people who are older adults have a much more fluid kind of relationship the time and they may not suffer from as much jet lag so it just depends on your age and your individual preference. There is this idea of kronor type which is the type of sort of circadian timing that you have and some people are early-morning people, some people are late evening people and most of us are right in the middle of the day. But those people, bookends of kronor type are the ones who really suffer the most.
CAVANAUGH: Now, do students in medical school since we are learning all these things about sleep, are they learning how sleep affects help?
MEDNICK: Unfortunately sleep is not taught in medical school on a regular basis. There was one elective class at UCSD medical school that I give lectures that every year and that was by (inaudible) and it was kind of amazing because they're usually like for people in the class and that is with a huge amount of first-year medical students. So, you can see that it's a specialized area and people going to if they're going to be a pulmonologist or something but they don't study it even if they're going to do something else. It's a third of our lives and it affects everything. Every time you do a study you find oh my God, there's an effect on sleep again.
CAVANAUGH: Exactly and 42% of Americans were found in one survey saying they never or rarely get a good nights sleep during the week. That's shocking, isn't it?
MEDNICK: It is shocking and that is the difference between how you are sleeping during the week and how you sleep during the weekend if there's a large discrepancy between those two that's how you know you're high on social jet lag.
CAVANAUGH: You are just not listening to your own body really is what it is?
MEDNICK: It's not you, it is the world. I mean I'm sure someone could listen to their own rhythm, they would. It is more that we have these kinds of things called work, and class, and
MEDNICK: Right, so it's very hard I think it would be a great idea now that we are so forward thinking and having people work at home I mean obviously Yahoo change the workout coffee is obviously there are many ways we can adapt to our schedules and those people have the benefit and I get people calling your e-mailing me and think I work at home and therefore I can nap indiscreet because I studied happening, obviously but the people who don't, in these kinds of businesses it would be great if we could even stagger work start schedules the way that we learn to stagger school start schedules now. There's PTA driven changes in schools where now they realize that these kids really need to be asleep during the time they have the hardest classes, so let's start the class at 9 AM, and they see improvements in performance.
CAVANAUGH: I'm speaking with UC Riverside psychologist Sara Mednick and she is a sleep researcher and I'm just wondering from your perspective what constitutes a good night sleep?
MEDNICK: That's a good question. Again it's sort of different for everybody, but I would say one where you, even if you, it is normal to wake up at night, so one thing that I think that people worry about is if they wake up at night, they start to get nervous that they will not sleep well, or there is something wrong we feel like there must be a solid night of sleep and there's a little bit of a misnomer that may be causing more insomnia than anything else. So it's possible that you could be awake during different periods of the night. The best thing that constitutes a good night of sleep is how you feel the next day. You wake up and feel refreshed you feel like you could have enough sleep that you could continue for certain amount of time during the day and take a nap later even if you can take a nap could you continue on I think to me that is the best metric.
CAVANAUGH: Can people actually catch up on sleep with naps?
MEDNICK: Yes absolutely a lot of the research we have shown that naps are as effective for many of the different behavioral and many benefits we see with nocturnal sleep that naps are as effective.
CAVANAUGH: Okay, let me get this straight, I'm not a good napper. Is that also something that comes with your own personal sleep rhythm, whether you are a good napper?
MEDNICK: It's a very good question. We are just beginning to understand there's some indication there may be some genetic differences between people who are sleepy during the day who can take naps and people who cannot because I know people like you who say I can not, I don't know what it is but I don't do it in other people like me left to nap. So it is an interesting thing. Was going on at the circadian phases during the day that allow some people to seem to really be able to sleep during the period of time and wake up and feel great versus when I try to get my husband to fall asleep during that date he wakes up and feels really terrible. So I don't think it's the same for everybody but at the same time can't you learn to nap, is another question we are looking at the genetic aspects of napping and whether we can do nap training on subjects.
CAVANAUGH: Your team of researchers just published interesting study about sleep and memory. Can you tell us a little bit about that?
MEDNICK: Sure, we know that sleep stages in certain phases of sleep to be correlated with different kinds of memory improvement. But what we do not know is if we can causally change those sleep features with drugs. Or anything even some sort of stimulation could we change the memory questioning that would mean that there's a causal relationship between the sleep feature and the memory so we used a really common ground, we use Ambien and what we found is when you actually give people Ambien during a nap you find increases in verbal memory. And that is amazing, so in a 90 min. You can have 90 min. verbal memory nap so if you want to have a boost in verbal memory, just have Ambien during sleep, why is that we look at the different sleep features and we found that Ambien specifically increases something called sleep spindles which is a feature of non-REM sleep and is a correlation between sleep spindles and the amount of sleep spindles and the amount of verbal memory increases.
CAVANAUGH: So this in some way consolidates the verbal memory. What do you mean by verbal memory, is this an actual tests that people are given before they fall sleep?
MEDNICK: Exactly, so we've given different battery of tests which is really you are given two different words and you're given a list of two different words (Word Association and you have to remember what the Association was steaming between one word and another word and it's very similar to anything with a face and a name, having to remember those two things are somebody's phone number and where they live, two different tags you might know about somebody or something and (inaudible)
MEDNICK: (inaudible) Stick around remember them later.
CAVANAUGH: You feel that that drug has an effect in increasing people's memory to remember things like that. Can you extrapolate that to health (inaudible)?
MEDNICK: Older adults and people with sort of pathological aging such as dementia and Alzheimer's, they all showed exactly this kind of memory deficit with associative memory, specifically declared of associative memory find deficits in these groups. Interestingly, they also showed decreases in sleep sleep spindles which is the exact sleep future we are able to enhance with Ambien. So, the question is, is it possible that we could start to use sleep as a tool for treating older adult age problems.
CAVANAUGH: That is exciting. There was a study that came out earlier that Ambien sort of decreases lifespan.
MEDNICK: There's all sorts of problems with Ambien. There's all sorts of, people who have all sorts of they wake up and do things they do remember, amnesia, and you do things that you did not necessarily want to do, so Ambien itself is not thing that we are trying to figure out. It's more sort of a means to an end. We like to figure how we could pharmacologically or otherwise increase sleep spindles because that seems to be the real trigger for increasing memory consolidation and down the line for being able to sort of retard the effects of memory degeneration in older adults.
CAVANAUGH: it is a means to an end, I understand your point. I once heard a sleep researcher give advice that one way to get a good nights sleep is not to useyour bedroom as an office or living room. You don't use it for anything but rest, relaxation and getting some sleep.
MEDNICK: That is exactly right. We always say it is sleep and sex and everything else has to be outside the bedroom. The problem here is that even having a communal so the circadian rhythm is guided by light and even the small amount of light you get from your alarm clock can also be disturbing so if you find a way to have an alarm clock without letting your room that's also beneficial and try not to watch TV in the living room and try to do your work outside the bedroom so that when you get to the bedroom you don't have any associations with the bad or the bedroom, or the space, or the table over there with anything other than a good space rest.
CAVANAUGH: So many people do that they have TVs and work in the bedroom that is there retreat that's where they can have private time.
MEDNICK: I completely understand the problem there and there was a national sleep foundation a couple years ago they were looking at sleeping families. They found a huge amount of young kids had TVs in the room. It's not even just TVs, it's all the different personal computers and iPhones and all the things that we have. Those things really need to be taken away from kids when they are young after a certain period of time because they are also very vulnerable to the effects of circadian phase delay. So the more you can do to kind of create a really nice quiet dark stable space for them without distraction, the better.
CAVANAUGH: Let me ask you in closing, Sarah, more than 20,000 people have signed the petition on the White House website to get rid of daylight savings time. You think that should happen?
MEDNICK: I think it's a great idea. I don't see any benefit for. Now we have so much control over the use of light in the use of heaters and energy. That was why we instated daylight savings and there doesn't seem to be any real justification now for any of those kinds of older reasons.
CAVANAUGH: considering what we know about sleep etc.,
MEDNICK: The payoff is just not good enough, I think
CAVANAUGH: So you be the 20,001 person to sign it I think.
MEDNICK: I guess I will
CAVANAUGH: I've been speaking with UC Riverside professor Sara Mednick, she's the author of Take a Nap, Save Your Life. Sara, thank you so much.
MEDNICK: Thank you so much