The lecture discusses the functions of sleep, dreams, the unconscious mind, and its manifestations.
Why Do We Sleep?
Theories explaining the reasons for sleep include:
Physiological reasons
Memory consolidation
Reduction of environmental stimuli
Psychologists explore what happens during sleep.
5 Stages of Sleep
During a night, a sleeping individual goes through four to six cycles.
Each cycle consists of five different stages.
Each cycle lasts between 90 and 110 minutes.
Quantity and Quality of Sleep
Two types of sleep: N-REM (non-rapid eye movement sleep) and REM (rapid eye movement sleep).
Deep N-REM sleep benefits memory consolidation and recharges the immune and cardiovascular systems.
Deep REM sleep benefits creativity and processing emotional stressors.
The link between sleep quantity and quality is congruent.
REM cycles are more frequent and deep after several N-REM cycles, meaning more sleep hours provide better quality sleep due to more deep REM cycles.
Links to Psychology and Biology
Lack of sleep can lead to sleep disorders and distortion of reality.
Sleep helps distinguish between reality and fiction.
Lack of sleep is associated with memory diseases like Alzheimer's.
Lack of sleep is associated with memory diseases such as Alzheimer's due to a build-up of beta-amyloid protein in the brain that is not "cleaned up" by your glymphatic system.
The glymphatic system removes waste from the central nervous system of the brain, mainly during sleep.
Sleep can affect our life choices and behavior.
More sleep is linked to more strong activity in neural pathways.
More sleep leads to positive mental health (REM!!!).
Dreams
Dreams are an important aspect associated with sleep.
Why Do We Dream?
Many possible theories exist on why we dream:
To help us with memory
To forget unnecessary thoughts of the day
To keep our brains active
To practice life scenarios
To find solutions to problems
To heal ourselves (from stress or tragedies)
To satisfy our desires
Freud's Interpretation of Dreams
Freud was the first modern psychologist to seriously study dreams.
He wrote "The Interpretation of Dreams" about dreams and their meaning.
Dreams have a hidden meaning and a language revealed through symbols, images, and wordplay.
Dreams are the manifestation of hidden desires or morality.
When interpreted, dreams express secret impulses and wishes that would be threatening if expressed while awake.
Freud: Silliness or Science?
Freud's approach to dreams was widely criticized for being too subjective and focusing too much on the sexual meaning of dreams.
Many contemporaries believed that even if dreams were symbolic, they could not be interpreted accurately.
Cognitive psychologists suggest dreams may be a way for the mind to organize, analyze, and reflect on the experiences of the day in memory.
Example: After stressful experiences or intense learning sessions, REM sleep tends to increase.
Lucid dreaming: the state of being consciously aware, while sleeping, that you are dreaming. Lucid dreams are a tool for mind relief.