1 of 22

Counting Sheep: The Many Ways Sleep Apnea Leads to Cognitive Impairment

Shubhangi Awasthi

Faculty Advisor: Brittany Holtzman

On-Site Mentor: Dr. Farrukh Qureshi, Neurologist

Dr. Yeeshu Arora, Neurologist

April 17, 2017

2 of 22

Research Question

  • What is sleep apnea and how does it affect the structure of the brain and cognitive abilities?

​

  • Significance: seriousness of sleep apnea
    • Often underdiagnosed
    • Can cause a long-lasting brain injury

​

3 of 22

Background

  • Initially researched several sleep disorders:
    • Insomnia: problems falling/staying asleep
    • Narcolepsy: tendency to fall asleep when in relaxing environments
    • Sleep apnea: breathing stops during sleep
  • Went deeper into sleep apnea after starting internship

4 of 22

Background-Sleep Apnea

  • Breathing stops momentarily during the night
  • Two types:
    • Obstructive (OSA): throat muscles relax
      • Most common type
    • Central: brain cannot send signals

5 of 22

Symptoms

  • Snoring
  • Sudden awakenings
    • Accompanied by gasping
  • Waking up with a dry mouth
  • Excessive daytime sleepiness

6 of 22

Risk Factors

  • Weight gain
  • Narrow airways
  • Neck circumference
  • Family history
  • Gender
    • Diagnosed more in men
    • Pregnant women have a higher risk

7 of 22

Research

  • Conducted observational research
    • Observed patients’ characteristics and symptoms

​

  • Read articles and books

8 of 22

Results

  • Many OSA patients show some cognitive dysfunction
  • Affects attention, memory, and executive functions
    • Executive functions: processes that allow us to manage ourselves (ex: prioritizing tasks)
      • Includes working memory and problem solving

9 of 22

Results-Reaction Time

  • Experiment:
    • Following sleep deprivation, subjects showed a decrease in speed in simple response time tasks and choice response time tasks
    • SRT task: one stimulus, one response
    • CRT task: multiple stimuli, each requiring different response

10 of 22

Results-Mental Arithmetic

  • Slower performance and increased errors
  • Neuroimaging
    • Conducted during subtraction task
    • Decreases in the prefrontal cortex (front part of the frontal lobe)
    • Abnormal activation in the parietal lobe (integrates sensory information)

11 of 22

Results-Executive Functions

  • Problem solving and planning
    • Longer response time on The Tower of London Test
    • Deficits on the Torrance Test of creative thinking

12 of 22

13 of 22

Results-Executive Functions

  • Working memory
    • Memory that temporarily holds information for processing
    • Simple working memory tasks have decreased response times and reduced accuracy
      • Rely more on attention

14 of 22

Results-Memory

  • Sleep is important for consolidation of memories
  • Impacts brain’s capacity to commit new things to memory
  • List-learning test showed recall of fewer words

15 of 22

Results-Language

  • Reduced clarity
  • Changes in intonation
  • Increased slurring
  • Reduction in pitch and loudness

16 of 22

Internship Experiences

  • Patient visits:
    • Memory patient (77 years):
      • Memory problems had gotten worse over 10 years
      • Experiences dizziness and headaches
      • Has lung disease
      • No light sensitivity, vision problems, or nausea
      • MMSE: 24 (no dementia)
      • Slurred speech

17 of 22

More Experiences

    • Seizure patient (32 years):
      • Suffers from anxiety and PTSD
      • Sleep problems:
        • Has sleep apnea
        • Nightmares
      • Needs to get a sleep study done
      • Shows how complicated sleep problems can be

18 of 22

Analysis

  • Sleep loss and deoxygenation caused by sleep apnea affect cognition
    • Cause structural change in brain
  • Sleep loss also speeds up brain tissue loss and memory loss
    • For example, people with dementia
  • CPAP Therapy is really effective
    • Reverses brain tissue loss

19 of 22

Future Research

  • Do an experiment on sleep apnea patients
    • Check for cognitive deficits like memory or attention problems

20 of 22

Conclusion

  • Sleep is very complicated
  • Causes disrupted sleep and deoxygenation
    • Results in brain tissue loss
    • In many areas that are responsible for cognition
  • Patients’ MRIs and scans have shown morphological changes in the brain
    • Medical histories have shown symptoms of mild cognitive impairment

21 of 22

References

  • 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.
  • Judd, Sandra J. Sleep disorders sourcebook. Detroit, MI: Omnigraphics, 2010. Print.
  • 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.
  • Mckinnon, Andrew. "Objective sleep disturbance in mild cognitive impairment is associated with alterations in the brain’s default mode network." Journal of Sleep Disorders & Therapy 05.06 (2016): n. pag. Web. 3 Feb. 2017.
  • Scullin, Michael K. "Sleep, memory, and aging: The link between slow-wave sleep and episodic memory changes from younger to older adults." Psychology and Aging 28.1 (2013): 105-14. Web. 3 Feb. 2017.
  • Casey, Sarah J., Luke C. Solomons, Joerg Steier, Neeraj Kabra, Anna Burnside, Martino F. Pengo, John Moxham, Laura H. Goldstein, and Michael D. Kopelman. "Slow wave and REM sleep deprivation effects on explicit and implicit memory during sleep." Neuropsychology 30.8 (2016): 931-45. Web. 3 Feb. 2017.
  • 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.

​

22 of 22

Thank You!

​

BASIS Phoenix

Ms. Brittany Holtzman

Dr. Farrukh Qureshi

Dr. Yeeshu Arora