Wrapping It Up

Hello all,

This is it. Tomorrow is my last day at Phoenix Neurological Institute. I can't believe how fast time has gone by. I still remember how scared I was to start interning back in February. I didn't want to drive all the way to Chandler three times a week.

Now, I can say I am very glad I got this opportunity. I learned a lot under the mentorship of Dr. Farrukh Qureshi and Dr. Yeeshu Arora. I would like to express my gratitude for allowing me to intern with them. Both of them let me get involved and ask questions and I learned things that I will never forget, such as life lessons.

I would also like to take a moment and thank BASIS Phoenix for giving me the chance to pursue a Senior Research Project and I would like to thank Ms. Brittany Holtzman for guiding me and helping me find the correct resources for my research.

This research project has been a success and has taught me a lot. I will be sharing my experiences with everyone at the presentations next Sunday, May 6. My presentation is scheduled at 10 am in the Gym and is open to all. I look forward to seeing all of you there and sharing my experiences with you.

I have attached my final presentation. Once again, thank you to everyone who has made this project a big success and great experience for me. I can happily say that I have learned many things that will stick with me for the rest of my life!

Warm regards,
Shubhangi Awasthi
BASIS Phoenix
Class of '17

Senior Project Presentation

Sleep Apnea and Cognition, pt 3

This is it! My second-to-last post! We are almost done!

In this post, I will be talking about the effect sleep apnea has on executive functions and memory. Executive functions are the processes that allow us to manage ourselves. They allow us, for example, to prioritize tasks, tell right from wrong, etc. Working memory and problem solving are one of the examples of executive functions.

Executive functions:

• Problem solving and planning: In a study done, subjects were timed to see how long it took them to complete the Tower of London Test (a video is attached below). Sleep apnea patients consistently had a longer response time. The Torrance Test of creative thinking was also performed, and deficits on this test were observed in sleep apnea patients.
• Working memory: Working memory is the memory that temporarily holds information for processing. Subjects in a study were given simple working memory tasks. An example is asking the subject to read multiple sentences and remember the last word of each. Decreased response times and reduced accuracy were observed in sleep deprived individuals and sleep apnea patients. This can also be explained by the fact simple working memory tasks require attention, but attention is impaired in sleep apnea patients.

Description of Torrance Test of Creative Thinking

Sleep deprivation also impacts memory in other ways. Sleep is important for the consolidation of memories. Different kinds of memories are consolidated in different stages of sleep. For example, REM sleep plays a crucial in the consolidation of procedural memory. Procedural memory is the memory responsible for knowing how to do things and motor skills. Thus, sleep apnea and sleep deprivation impacts the brain’s capacity to commit new things to memory.

Sleep Apnea and Cognition, pt 2

From reading articles, I have found out about many different experiments done to test for deficits in cognitive abilities in sleep apnea patients.

Response Time Experiment:

Sleep apnea patients showed a decrease in speed in simple response time tasks and choice response time tasks. Simple response time tasks are tasks in which one stimulus is given and one specific response is expected. An example would be a task in which a light is the stimulus and every time the subject sees the light go on, he has to press a certain button.

A choice response time task in one in which multiple stimuli are given and each stimulus requires a different response. An example would be a task in which the stimulus is seeing a letter on the screen and the response would be pressing the corresponding letter key on the keyboard. A study done showed that sleep apnea patients had a decreased reaction time for both kinds of tasks.

Short-Term Memory:

On auditory, spatial, or visual short-term memory tasks, the accuracy of the performance of OSA patients has been mixed. However, imaging of the brain has brought clearer results. Sleep deprivation in OSA patients has shown decreased activity in the intraparietal sulcus (IPS), the green line in the picture below. The IPS plays a key role in processing numbers and in visual working memory (I will talk about this in the next post). The reduction in this region of the brain was linked to a reduction in the memory capacity shown by the study.

Mental Arithmetic:

In mental arithmetic studies, sleep deprived patients have had slower performances and more errors. The study shows that small decreases in sleep and disturbed sleep can severely affect performance on tasks similar to the ones done.

Neuroimaging conducted during the serial subtraction task also showed decreases in the prefrontal cortex, the front part of the frontal lobe (shown below), which is responsible for tasks like problem solving and processing complex thoughts. It is also known to play a role in emotions. Imaging also shows abnormal activation of the parietal lobe (shown below), which integrates sensory information.

These are only a few of the many things that are affected by sleep loss and sleep apnea. I will go further into executive function in my next post.

Stay tuned!
Waters, Flavie, and Romola S. Bucks. "Neuropsychological Effects of Sleep Loss: Implication for Neuropsychologists." Journal of the International Neuropsychological Society 17.04 (2011): 571-86. Web. 16 Apr. 2017.

Preparations for the End of the Year!

Hello all,

Yesterday, I finished up a rough draft of my final presentation. Watching all of my work from the last three months culminate into a final product like this was very satisfying. Now, I am working with my BASIS Phoenix advisor to make edits to my powerpoint. I have also started writing my paper and planned out how I will be doing my poster. In my opinion, this is the best part of the project because this is where I get to realize how much I have learned throughout my time at my internship. I am very excited to finish writing my paper and I can't believe the end of the year is almost here! Thank you all for joining me through this journey and I hope you got to learn a lot!

~Shubhangi 

CPAP!

One of the treatment methods for sleep apnea is Continuous Positive Airway Pressure (CPAP) therapy. CPAP machines gently blow air at a constant pressure through the airway to keep it from collapsing.

The Machine:

The CPAP machine has three main parts, the motor, the hose, and the mask. The motor takes in room temperature air and pressurizes it. This way, air at the best pressure for the patient is delivered. Most newer machines have a built-in humidifier. These machines are great for patients who wake up with a dry mouth or throat.

The hose is the part of the machine that transports the pressurized air from the motor to the mask. The CPAP mask is the part of the machine that delivers the air to the patient’s airway. Masks come in different shapes and sizes since not all people will feel comfortable wearing each kind of mask.

There are three main categories of CPAP masks:

1. Nasal pillows: lightweight and smallest and are ideal for claustrophobic people
2. Nasal masks: triangular shaped mask that fits over the nose
3. Full face masks: covers the nose and the mouth
   

Getting Set Up With CPAP:

From the patient visits I have been in with Dr. Qureshi and Dr. Arora, I have seen that the first step in getting CPAP is having a sleep study (polysomnogram) done at a sleep clinic. The results from this study will tell the doctor how severe the sleep apnea is.

If the doctor determines CPAP is the best option, then he orders a follow-up sleep titration sleep in which the patient sleep at a sleep clinic overnight. There, he tries on different types of CPAP masks and uses different machines to see which one best fits his needs. The technician determines at which pressure the patient’s AHI is the lowest.

After getting a CPAP machine, the patient must make sure he uses it regularly (every night). If he stops using it, the symptoms of sleep apnea can return.

Results:
CPAP is really effective for treating sleep apnea. It decreases the amount of daytime sleepiness the patient experiences and improves the overall quality of sleep. It also prevents serious health conditions like cardiovascular diseases and lowers blood pressure during the day and night. As I mentioned in my last post, studies have also shown that CPAP therapy has also reversed tissue loss in different areas of the brain.

Source: Reite, Martin, Michael P. Weissberg, and John Ruddy. Clinical manual for the evaluation and treatment of sleep disorders. Washington, DC: American Psychiatric Pub., 2009. Print.

Sleep Apnea and Cognition

So far, I have talked about how sleep apnea and other sleep disorders cause physiological problems such as more weight gain and a weakened immune system. In this post, I will be talking about how they affect the structure of the brain itself.

Sleep apnea is known to affect cognition and mood. Patients suffer from mood instability and show a lot of cognitive deficits, especially impairment to attention and executive function. They are also emotionally reactive.

The cause behind this is still being researched. One possible reason this may happen is that repeated episodes of the airway collapsing and the patient not breathing during the night causes a reduction in the amount of oxygen the tissues of the brain receive. This causes gray matter loss in different areas of the brain.

One such area is the frontal cortex. This structure is responsible for executive function, or the self-regulation skills that allow us to plan things, manage time, and do other things. It is also associated with working memory.

Other areas in which gray matter loss due to sleep apnea occurs include the thalamus, the hippocampus (the structure that controls memory), and the amygdala (the structure that is associated with emotions). Therefore, this may be a reason why cognitive and emotional difficulties are seen in patients with sleep apnea.

OSA also causes tissue loss in the temporal and parietal lobes, which are responsible for attention and visual-spatial processing.

This tissue loss, however, is shown to be irreversible. Studies have been done which show that CPAP Therapy can reverse gray matter loss for OSA patients. CPAP Therapy is one of the treatment options for OSA patients and I will going further into it in my next post.

Source: Olaithe, Michelle, Shenooka Nanthakumar, Peter R. Eastwood, and Romola S. Bucks. “Cognitive and mood dysfunction in adult obstructive sleep apnoea (OSA): Implications for psychological research and practice.” Translational issues in Psychological Science 1.1 (2015): 67-78. 3 Feb. 2017.

Women Suffer More

Women are more likely to suffer from disturbances in sleep, and thus, sleep disorders. Biological conditions like pregnancy and hormonal changes can affect how well a woman sleeps. For this reason, many women suffer from sleep disorders like insomnia and sleep apnea.

Hormonal fluctuations during menopause and menstruation may cause women to not sleep well at night. They may also cause weight gain during menopause. Weight gain, as we know, increases the risk of getting sleep apnea.

Pregnant women are also susceptible to sleep apnea due to the weight they gain. Pregnant women who have sleep apnea are very prone to developing hypertension and diabetes. During pregnancy, hypertension can cause conditions like preeclampsia and eclampsia.

Preeclampsia symptoms include swelling of the hands and feet. When preeclampsia goes untreated, eclampsia occurs, which can eventually lead to coma and the death of the mother and the child.

Sleep disorders like OSA not only affect the mother but also the fetus. Sleep apnea restricts oxygen to the fetus, which can result in birth defects and developmental disabilities that can last for the child’s lifetime. The outcome of the mother’s oxygen level dropping and oxygen to the fetus being cut off is unpredictable and scary.

Source: Reite, Martin, Michael P. Weissberg, and John Ruddy. Clinical manual for the evaluation and treatment of sleep disorders. Washington, DC: American Psychiatric Pub., 2009. Print.