Article Review: How Quality of Sleep Affects The Brain

The purpose of the research performed in this article was to analyze how quality of sleep affects the brain. The research question was whether sleep quality is associated with cortical and hippocampal volumes as well as measures of atrophy in the brain. It was hypothesized that poor sleep quality is associated with decreasing volume while increasing atrophy in the orbitofrontal cortex and the medial prefrontal cortex.

To test the hypothesis an MRI was given to the participants between 2006 and 2009. Next, a second MRI was given between 2011 and 2012. Finally, a sleep quality assessment was tested between 2012 and 2013. The same MRI scanner and process stayed the same throughout this study. The MRI images were processed individually followed by longitudinally. The sleep quality assessment was a questionnaire used to assess the seven domains of sleep quality. The researchers also analyzed other factors such as physical activity, BMI, and blood pressure. The factors were measured when the participants came in for the second MRI through questionnaires and the appropriate tests. At T2, the cross-sectional cortical analysis was run at each vertex of the brain as the dependent variable. The PSQI score from the sleep analysis was used as the independent variable. Similarly, the longitudinal cortical analysis used a general linear model to study the change in volume from T2 and T1. The change in volume that was measured at each cortex was the dependent variable with the PSQI score as the independent variable. The influence of outliers and other possible effects such as physical activity and BMI were also taken into consideration. All of this data was then used to determine which aspects of sleep align with the results the most.

The results of this research determined that poor sleep quality was linked to reduced volume in the superior frontal cortex. Additionally, poor sleep quality was associated with increased atrophy in the frontal, parietal, and occipital lobes of the brain. It was also determined that other factors such as physical activity, BMI, and blood pressure were not associated with the sleep analysis score, or PSQI. These results align with the hypothesis that poor sleep quality is linked to decreasing volume while increasing atrophy in the orbitofrontal cortex and the medial prefrontal cortex.

The goal of the CNN article was to summarize the research that was conducted on how poor sleep affects the brain. They explained the study was tested with two MRI scans and a questionnaire about the participants sleep habits. The data they concluded stated that those with poor sleep patterns showed a faster decline in brain volume. It was also concluded that those over the age of sixty demonstrated these patterns the most. The purpose of the article was to make the point that poor sleep patterns can lead to brain disorders that cause memory loss, therefore shrinking our brains. At the end of the article, they chose three statements from the original article. All three statements lead to the fact that more tests need to be done and that there are many questions to figure out.

The author of the popular press article uses causal language when making the statement that a lack of sleep affects the size of our brain. Causal conclusions cannot be made from correlational studies because correlational studies do not predict outcome, they determine associations. Experimental studies are the only studies that can use casual language. An experimental study determines a casual relationship between two variables. The original research article is a correlational study because there were no cause and effect statements and variables were not altered.

The author fails to mention in the popular press article that a possible third variable could be associated with sleep quality and changes in brain structure. An example of a possible third variable could be severe depression or anxiety symptoms. I did find that not all of the information was accurate in the popular press article. The age range of the participants was too big of a range compared to the original article. The popular press article used casual language which could be misleading and also left out a lot of data on the study. However, they concluded the article with statements that prove that there is no cause and effect relationship yet.