A Short Review of Sleep, Attention and Learning

ABSTRACT

The “Growing Up” years are learning years. During these years, the quality of education plays an important part in shaping the future development of individuals and is essential for success in life. Ambitious students during the academic years focus on studies and have little time for sleep, thinking that the more time they spend studying, the more they will learn.However, new studies and reserach indicate that less sleep is counter productive and decreases the learning capacity of the brain.This paper is a brief review of sleep, study habits of young people and brain function as it relates to learning ability.

INTRODUCTION

Our traditional understanding of the role of sleep has changed from being a state of brain and body rest to one of a survival role. During sleep, extracellular spaces in the brain dilate and allows for the removal of metabolic waste products(1). Sleep improves the quality of survival because the brain still learns while asleep and learning is cognition(2). During sleep, learning in the brain takes place in a highly developed dynamic complex interaction between different parts of the brain. Thus, sleep is the time for memory consolidation processes(3). With this fundamental understanding of the brain sleep function for learning and wellbeing, we can improve the academic performance and general health of our young people(4).

Learning, Awakening and Attention

Learning occurs during the waking hours where a constant flow of information enters the brain but only a fraction of the information becomes available to our conciousness(5,6). The information is encoded and streamed into structures in the hippocampus.(7,8).

The brain encodes not only what we want to remember, but all incoming information, some things we are aware of conciously as well as events in the our borderline active attention and conciousness (9). For example, if one studies in a room with flowers, all information is encoded in short-term memory, including the smell, associated time, space and associated events to be remembered.

Different levels of alertness occur during the waking hours. Upon awaking, we are more alert but alertness declines during the day (10) and our function for attention declines. The high level of alertness increases our attention for better encoding (11, 12, 13, 14). It has been shown that a mid-day nap improves encoding ability in sleepy young students (15). The ability to pay attention may be a key factor for academic success and compensate for differences in IQ in a group of learners (16).

Short term memory has limited, fragile and vulnerable storage and is distracted by a constant flow of information. For example, most people have difficulty remembering random series of more than five or six digits without rehearsal and focused attention.This information is remembered for a few seconds, encoded and then erased(17, 18, 19).

For proper encoding of information, the brain needs to pay attention and rehearse the information for appropriate encoding. Students need to read the information to be learned, rehearse the information so that the information can be put into context during the reading and then transitioned for decent encoding to take place.

Learning, Memory and Sleep

For true learning and retention of information, short-term memory needs to be transformed into long-term memory storage(3).The long-term memory information can later be retrieved for planning and performance (20). The transition from short-term to long term memory does not happen directly but requires a specific encoding process(21). During the process, encoded information is stripped from the context, abstracted and integrated with existing memory material(21, 22). In addition, the information is reconsolidated with previous memory and new information and only the essence of the encoded information in short memory will be included in our knowledge (23). This process is not well understood but takes place predominantly during slow wave sleep pattern (21, 23).

Short-term to long-term transition hypothesis can be explained by the active consolidating processing hypothesis which occurs during slow wave sleep.

Sleep in the Developing Brain Relevant for Learning

Profound sleep changes occur from childhood through adolescence(24). For adolescents, sleep deprivation is a risk factor with social and behavioural changes during this time. The optimal hours of sleep for teenagers is eight to ten hours and longer with younger childern. Unlike teenagers, younger children get sleepy earlier in the evening and wake up early while teenagers develop a different gradual sleeping pattern and sleeping difficulties. Although there are individual variations, this pattern is one of sleeping late (11pm-12 midnight) but having to wake up early for school; thus, they develop sleep deprivation patterns (25).

In Myanmar, sleep deprivation for students, especially in the high school years, is a huge challenge with school hours, family obigations and “tuition”, which is family-funded tutoring outside of school. Students have little time with their days starting at 5-6 am and studying till midnight.This high pressure for education results from the family’s concern regarding the children’s future and family prestige which is linked to children achieving a good education. Thus, many Myanmar school children are at risk for sleep deprivation. Studies have shown that sleep deprivation in children is unhealthy and counter productive with lower academic performance(26). This occurs with sleep deprivation since the information encoding deteriorates in the later hours of the night. Sleep deprivation in the adolescent years promotes other unwanted consequences: increased risk of adiposities, anxiety, headache, depression, decreased motivation and impaired immune system(27). Other consequences termed “ten- standard syndrome” include: sleep disturbances, learning disabilities, tiredness and dizziness. Help for this desperate situation include education for families and medical emergency measures.

Conclusion: To improve the academic performance and health of students ( physical, emotional, psychological), the importance of adequate sleep and avoidance of chronic sleep deprivation needs to be shared with families, students, educators and the education system. This important public health message is necessary for improving student academic performance and preparing them for adulthood in our society.

Acknowledgement: I thank Dr. Kjeld Hougaard for inspiration and support.

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