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Journal #38--Sleep Extension Discussion (Updated/Revised)

Submitted by skhall on Mon, 05/01/2017 - 18:45

        The conclusive data indicate that developing children are able to extend their sleep by a significant amount during overnight sleep. Post 5 days of experimental sleep extension (1.5 hours earlier than their normal bedtime) children increased sleep duration by an average of 56 minutes. Sleep onset in the extension condition was 1 hour and 8 minutes earlier compared to the baseline condition. Previous studies have shown a 27-minute increase with a 1-hour earlier bedtime, but this study has a more vivid effect. Longer onset sleep did not cause a significant difference in the time in specific sleep stages. REM theta activity was not significantly reduced as hypothesized at the frontal electrodes. However, REM theta activity was reduced during the sleep extension condition at parietal P3 electrode.

         These results as well as Go/No-Go task results can indicate behavioral changes. Inhibitory control was improved in the morning compared to the evening. There was no significant different in inhibitory control between the baseline and sleep extension. This could be due to children having a sufficient amount of sleep or inhibitory control. The task may also not cover all effects that sleep extension has to show significant results (Gruber et al., 2012; Sadeh, Gruber & Raviv, 2003; Vriend et al., 2013). 

         This sample of children slept a normative amount for the 6-9-year-old age group. The average sleep duration in this study was 10 hours, which could explain why the children may have not benefited from the sleep extension compared to those who sleep less. In previous studies, children slept 8.5-9.5 hours which is why there could have been significant results previously (Gruber et al., 2012). ​ Similarly, children may have already had adequate inhibitor control. The task could have also been too easy not allowing children for room of improvement between sessions to see substantial results.

         Some correlations were determined from the conclusive data. REM theta activity was correlated with morning inhibitory control during the baseline condition. This could indicate that shorter sleep may make theta activity more efficient. Meaning, that theta activity causes beneficial behavioral effects for children. Longer sleep causes less stress on the child, so behavior will not improve if the child is already at adequate cognitive levels. Again, there was no significant data in sleep extension for REM theta activity so correlations cannot be determined.

      Additional data from our lab indicate that theta activity is elevated in children diagnosed with attention-deficit/hyperactivity disorder (ADHD). High amounts of theta activity are not beneficial to inhibitory control in this sample. Due to this, it is assumed by this study that there is an optima amount of theta activity of sleep extension. Further studies will take place to determine if sleep extension alter theta activity enough to improve inhibitory control in children diagnosed with ADHD.

Journal #37--Sleep Extension Results Revised

Submitted by skhall on Mon, 05/01/2017 - 12:56

To date, 15 participants have been tested, data collection upon participants vary. Total sleep time (TST) and sleep onset time between the baseline and extension sleep periods each had a p-value less than 0.001 (n=14). This Actigraphy data indicates that children are going to bed earlier and sleeping longer based on the sleep onset time and TST.  Paired-sample t-tests were constructed to compare sleep stages and REM theta activity, between the baseline and sleep extension conditions (n=10). REM theta activity was not significantly reduced during the sleep extension condition (n=10). Data from the Go/No-Go task indicates that inhibitory control levels improved following the overnight sleep in the baseline condition (n=14). Inhibitory control has not been improved thus far following the sleep extension condition. During baseline condition, REM theta activity was positively correlated with morning inhibitory control (p=0.048). There was no significant correlation between REM theta activity and morning inhibitory control during extension condition.  

PP Sleep Extension Results (Revised)

Submitted by skhall on Mon, 05/01/2017 - 11:25

To date, 15 participants have been tested, data collection upon participants vary. Total sleep time (TST) and sleep onset time between the baseline and extension sleep periods each had a p-value less than 0.001 (n=14). This Actigraphy data indicates that children are going to bed earlier and sleeping longer based on the sleep onset time and TST.  Paired-sample t-tests were constructed to compare sleep stages and REM theta activity, between the baseline and sleep extension conditions (n=10). REM theta activity was not significantly reduced during the sleep extension condition (n=10). Data from the Go/No-Go task indicates that inhibitory control levels improved following the overnight sleep in the baseline condition (n=14). Inhibitory control has not been improved thus far following the sleep extension condition. During baseline condition, REM theta activity was positively correlated with morning inhibitory control (p=0.048). There was no significant correlation between REM theta activity and morning inhibitory control during extension condition.  

Journal #36--Sleep Extension Discussion

Submitted by skhall on Wed, 04/26/2017 - 11:34

The preliminary data indicate children are able to extend sleep. However, to date, sleep extension does not seem to impact inhibitory control. This could be due to the participants already having a sufficient amount of sleep. In the next few months, additional data will be collected to achieve the full sample of 15 participants. PSG will be scored to determine if the sleep extension altered SWA and theta activity. If the results show that sleep extension improves behavior, then sleep extension can potentially be used as an intervention to enhance cognitive functioning in children.

Once all data is collected, we expect that there will be a positive relationship between theta activity and inhibitory control at the baseline condition. In the sleep extension condition, theta activity will be reduced and inhibitory control will be greater, relative to the baseline condition. Thus, it is expected that sleep extension will have a strong effect on inhibitory control.

Additional data from our lab indicate that theta activity is elevated in children diagnosed with attention-deficit/hyperactivity disorder (ADHD). High amounts of theta activity are not beneficial to inhibitory control in this sample. Due to this, it is assumed by this study that there is an optimal amount of theta activity. of sleep extension. Further studies will take place to determine if sleep extension alter theta activity enough to improve inhibitory control in children diagnosed with ADHD.

Journal #35--Peer Review Fraud

Submitted by skhall on Tue, 04/25/2017 - 08:08

   On Facebook today I saw an article that someone had shared about cancer papers being retracted for fraud through peer reviews. The authors that published such research papers (107 to be exact) faked the peer review process. Apparently this isn’t the first time this journal has done this. Last year, 58 of the journal’s papers were retracted from 7 different journals…for the same reason. . "There is some evidence that so-called third-party language-editing services play a role in manipulating the reviewing process,” said a spokesperson. The argument is whether they let it go knowing the the authors most likely knew what they were doing. However some believe they can get away with it because there’s most likely nothing wrong with the research, it just hasn’t been peer reviewed. “It is unclear whether the authors of the manuscripts were aware that the agencies were proposing fabricated reviewer names/e-mail addresses.” This recent fraud was noted when there happened to be an extra screening of the journal. I find this process interesting because I would think that these journals doing the publishing and editing would notice that this group has had issues with this in the past. If they are not willing to take the time to work through their writing and make it valid for the readers and further journals, why are they doing all of this work?

Journal #34--Naked Mole Rat

Submitted by skhall on Mon, 04/24/2017 - 10:31

   This week while looking through biological news, I found an article discussing the “bizarre biology of the naked mole rat.” It begins talking about the species as a whole and their amazing features. From withstanding cancer, pain and surviving 18 minutes without oxygen, there is much to learn about this animal. Scientists are discovering even more about this “super rodent.” The animal lives in large colonies that  an reach up to 280 animals…wow. They are found in Africa, living in underground tunnels in the desert where there is a very low oxygen supply. In humans, such a lack of oxygen would cause hyperventilating and acid build up in our tissues causing brain damage and even death. However, for the naked mole rat, lack of oxygen is the least of their worries. In order for scientists to test the real ability of this animal and its lack of desire for oxygen, they created a controlled environment that is essentially a tube that seals off all oxygen. When oxygen levels were dropped to even 5% the rats were fine for five hours. Mice on the other hand only lasted approximately 15 minutes before suffocating. The big question is how the rats do it. The naked mole rat switches to using fructose in the body so its levels are higher to help the vital organs survive. Scientists have not determined where the fructose levels are rising in the body, but that is for further research.

PP Sleep Extension Methods

Submitted by skhall on Fri, 04/21/2017 - 12:14

A Go/No-Go task will be used to measure the cognitive functioning of the child, specifically inhibitory control. During the Go/No-Go task, children will be told that they need to catch animals that have escaped from a zoo. To catch the animals, they are to press a button on a mouse as quickly as possible. They are instructed to catch all animals except for the chimpanzee because the chimpanzee is helping to catch the other animals. Children will have one practice round and two sessions of the actual task. If children click the mouse when the chimpanzee pops up, they are reminded not to catch him in order to help with the task at hand. Additional questionnaires will be used to assess the behavior and sleep in the sample tested.

Journal#33--Sleep extension Methods and Results

Submitted by skhall on Thu, 04/20/2017 - 10:00

**Ignore blue font, it is from the editing process.** 

 

Methods

Participants

Data will be collected from 15 participants. Participants must be between the ages of 6 and 9. The child must sleep less than an average of 10 hours a night and an average bedtime of 8pm of weeknights. Children must sleep less than 10 hours because they may not be able to extend their sleep further. It is expected that children have an average bedtime of 8pm so the extended sleep does not interfere with any evening activities. Children must have no history of neurological disorders, visual or hearing impairments or sleep disorders.

Measures

            This study will use various measures to assess sleep in our participants. An actigraphy and caregiver sleep diary will  be used to evaluate the child’s bedtimes and wake times and compliance with the sleep manipulations (i.e., extension). Children will be asked to press a button on the watch when they are going to bed and again when they wake up in the morning. Caregiver’s will be asked to log the child’s sleep and wake times during experimental testing in a daily sleep diary. Sleep diaries will be used to confirm the scoring of the actigraphy.

 Polysomnography caps (PSG) will be used to assess sleep physiology during the overnight visits in the lab. This data will be used to measure time spent in different sleep stages as well as SWA and theta activity.

A Go/No-Go task will be used to measure the cognitive functioning of the child, specifically inhibitory control. During the Go/No-Go task, children will be told that they need to catch animals that have escaped from a zoo. To catch the animals, they are to press a button on a mouse as quickly as possible. They are instructed to catch all animals except for the chimpanzee because the chimpanzee is helping to catch the other animals. Children will have one practice round and two sessions of the actual task. If children click the mouse when the chimpanzee pops up, they are reminded not to catch him in order to help with the task at hand. Additional questionnaires will be used to assess the behavior and sleep in the sample tested.

Procedures

At the beginning of the study, children will be given an actigraphy watch to record their bedtimes and wake times throughout the study. Sleep diaries will be filled out by the caregivers in order to validate scoring of the actigraphy data. Children will complete both a sleep extension and baseline condition. Each condition takes place over 5 consecutive days. During the sleep extension condition, children will go to bed 1.5 hours earlier each night. During the baseline condition, children will go to sleep at their normal bedtime.

At the end of the baseline and extension conditions, children will participate in an in lab visit during which PSG caps will be worn to measure the sleep physiology during overnight sleep. During these overnight visits, children will complete a Go/No-Go task to measure the inhibitory control before and after overnight sleep.

 

Results

To date, data has been collected from 12 participants. The preliminary data from actigraphy indicate that children are extending sleep by approximately 1 hour. Total sleep time (TST) and sleep onset time between the baseline and extension, p ≤ 0.001. Actigraphy data also indicates that children are going to bed earlier and sleeping longer based on the sleep onset time and TSTInhibitory control (Go/No-Go task) indicates that it is improving following overnight sleep in the baseline condition. Sleep extension has not shown significant results for inhibitory control. The accuracy is reduced in this condition and the data will be further looked at. 

 

Journal #32--MIT receives $7.5 million to enhance structural biology research

Submitted by skhall on Wed, 04/19/2017 - 09:27

Recently I saw a post on Facebook about MIT receiving a $2.5 million gift from the Arnold and Mabel Beckman Foundation. This gift is to help create a cryo-electron microscopy that is on the MIT campus. MIT will also receive an anonymous $5 million donation for the university to buy a synergistic high-resolution cryo-EM instrument. The Cryo-EM is an X-ray that allows for scientists to look at biological structures at large. This specific X-ray allows for these scientists to determine the position of atoms in a biomolecule helping understand the structures of these organisms. This type of instrument has been used in major scientific discoveries such as the double helix in DNA, but the article noted it does have its limits. This instrument can also allow analyzation of cell communication.  Alan Grossman stated, “This revolutionary technology will enable ground-breaking innovations and insights in structural biology and therefore affect many areas of human health and disease.”  Similar grants have also been given to Johns Hopkins University School of Medicine, University of Pennsylvania’s Perelman School of Medicine, University of Utah, and University of Washington School of Medicine. These grants have allowed for schools to have a better understanding of biology as a whole and allow for students and staff to get a better hands on and visual experience.

Journal #31-- Learned Behavior

Submitted by skhall on Tue, 04/18/2017 - 10:31

I was recently reading an article about the learning among instictual animals and their ancestors. Two biology professors from the University of Illinois and Marcquarie University (in Australia) were analyzing a science journal that also suggest these claims, that these animals were likely "learned" by ancestors. The names of these two professors are Gwne Robinson and Andrew Barron. They believe that these specific behaviors are learned by ancestors are now in their DNA and have shown up in later generations. The article goes on to discuss that there are cleary certain traits that are instinctual to specific species, without needing to be taught. What the two biologists believe is that there is a form of natural selection that could lead to specific behaviors that are being used at early stages in development (more often than seen before). Though they do not have technology to see such a change in DNA, but they are also aware that such epigenetics is considered to be a young scientific topic and there is still much to discover, and this topic could be one.  

 



Read more at: https://phys.org/news/2017-04-biology-professors-instincts-evolved.html#jCp

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