SLEEPING  Sleep stages: Stage 1- Hallucinations Stage 2- Sleep spindles Stage 3- Transitional sleep Stage 4- Deep sleep

SLEEP CYCLE  There is a five stage cycle Repeats every 90 minutes  REM sleep  REM increases as night progresses

SLEEP NEEDS AND DEPRIVATION  Sleep needs in age groups: Newborns will sleep 6 to 8 times in a 24 hour period (more than 16 hours per day 6 year old child needs up to 11 or 12 hours of sleep per night As the child grows up they need less and less sleep until they are an adult only needing hours of sleep per night (they may need even less as they get older. During a whole lifetime we need about 1 hour of sleep to every 2 hours we are awake.

SLEEP AND MEMORY  When learning a difficult perceptual task and are kept up all night after finishing practicing the task, the learning is wiped out  Sleep after learning is essential for memory consolidation  The memory normally deteriorates unless sleep occurs.  **Pulling an all nighter to study for an exam is not the best option because the information being learned will not stick in your memory*** EXTREME SLEEP LOSS CAN BE FATAL!!

SLEEP DEPRIVATION  Sleep deprivation can have a detrimental effect even on the healthiest of young people; it can cause an increase in irritability, reduce acuity and reaction time, and increase depression. People who do not get enough sleep are also more prone to accident and injury.

REM SLEEP AND ITS IMPORTANCE  Memory problems and excessive aggression are observed in both humans and rats when awakened whenever the REM activity starts.

SLEEP DISORDERS  Medication: People use sleep medication to help with Insomnia but this is not always a benefit Most sleeping pills are addictive Sedatives can interfere with the normal sleep cycle Reduce the proportions of time spent in REM and slow-wave sleep Grogginess and irritability during the day Stopping the treatment to abruptly can cause insomnia worse than before.

DISORDERS  Insomnia: Difficulty in falling asleep or staying asleep About 15% of adults suffer from severe insomnia About 15% of adults suffer from a mild case of insomnia Causes for insomnia include anxiety associated with stressful life events.  Sleep Paralysis: The experience of waking up unable to move Associated with narcolepsy Only lasts a few moments and can cause pressure on the chest

DISORDERS CONT.  Sleep Apnea: Disorder in which the person stops breathing for brief periods while asleep. Occurs most often in middle-aged, overweight men Snoring and noisy gasping for air are some signs of sleep apnea Usually this disorder goes undiagnosed because it is easy for the sleeper to not notice. Sleep may seek treatment because of excessive sleepiness during the day. Some treatment include weight loss, drugs, or external breathing aids

DISORDERS CONT.  Somnambulism (Sleepwalking): Person arises and walks around while asleep. Common in children around the age of 11 or 12 25% of children experience at least one episode Sleepwalking happens early in the night usually during slow-wave sleep, and sleepwalkers may awaken during their walk or return to their bed without waking. Sleepwalker will usually not remember the sleep walk the following morning The eyes of the sleepwalker are usually open and glossed over when walking occurs. The only problem is the physical harm that can come to the sleepwalker by tripping over objects or falling down stairs. It is safe to wake a sleepwalker or lead them back to their bed if necessary.

THE LAST OF DISORDERS  Narcolepsy: A disorder in which sudden sleep attacks occur in the middle of waking activities. Attacks can last from 30 seconds to 30 minutes depending on the individual Is hereditary and runs in families and can be treated effectively by medication  Night terrors (Sleep terrors): Abrupt awakenings with panic and intense emotional arousal. Usually occurs in boys ages 3-7 Occur during NREM or at the beginning of sleep cycle and dreams are not associated with night terrors

DREAMING

 “Dreaming permits each and every one of us to be quietly and safely insane every night of our lives.”-William C. Dement (1959) 

5 MAJOR CHARACTERISTICS  1. We feel emotion  2. Dream thought is illogical  3. Sensation is formed and is meaningful  4. Dreaming occurs with uncritical acceptance  5. Difficulty remembering the dream after it is over

DREAM THEORIES  Sigmund Freud Dreams are confusing and obscure. Dynamic unconscious creates them to be confusing and obscure. They represent wishes and some are unacceptable, taboo and anxiety producing -Problem: infinite number of interpretations of any dream -BUT evidence that dreams do feature the return of suppressed thoughts.

DREAM THEORIES CONT.  Hobson and McCarley 1977 Activation-synthesis model: dreams are produced when the mind attempts to make sense of random neural activity that occurs in the brain during sleep. In the dream state mind does not have access to external sensations. The information is from neural activations without perception of reality. The interpretive mechanisms of the brain can run free!

DREAMING BRAIN  Different brain areas show activation during REM sleep.  Brain area responsible for fear or emotion work overtime in dreams. For example the amygdala (responses of stressed or threatening events) is quite active during REM  Areas responsible for visual perception are NOT activated, but visual association in the occipital lobe is activated

THE BRAIN CONT.  During REM sleep: Prefrontal cortex shows less activity The eyes move rapidly but the body is very still, so motor cortex activated but spinal neurons inhibit expression of motor activation

TEST QUESTION  What is one of the 5 signs of REM sleep? Possible answers: 1. pulse quickens 2. blood pressure rises 3. old tale of sexual arousal 4. very little muscle movement, the sleeper is very still 5. rapid side-to-side eye movement