Sleep stuff

The beta waves of an alert, waking state and the regular alpha waves of an awake, relaxed state differ from the slower, larger delta waves of deep Stage 3 sleep. Although the rapid REM sleep waves resemble the near-waking Stage 1 sleep waves, the body is more internally aroused during REM sleep than during NREM sleep





















Amygdala: Feelings and emotions


Occipital Lobe: Eyesight/vision.


Parietal Lobe: Spacial awareness, 


Temporal Lobe: Memory, hearing, understanding, etc. 


Sensory cortex: Feelings things


Frontal lobe: Decisions, problem solving, etc.


Cerebellum: Balance, coordination and motor skills


Corpus callosum: Fibers in the middle of the brain that connect the 2 

hemispheres.


Hippocampus: Short term memories - Long term memories


Hypothalamus = Homeostasis, temperature regulation, heartbeat etc.

Limbic System: Memory, emotions and behaviors. Contains pituitary gland, , hypothalamus, thalamus, amygdala, and hippocampus.














Thalamus = hearing, taste, sight and touch.

 1. The Brain

  • Brainstem:

    • Manages automatic survival functions (e.g., breathing, heart rate).

    • Key parts include:

      • Medulla: Controls heartbeat and breathing.

      • Pons: Aids in coordinating movement and plays a role in sleep and arousal.

      • Reticular Formation: Involved in controlling arousal and alertness.

  • Limbic System:

    • Plays a role in emotions, memory, and survival instincts.

    • Components include:

      • Amygdala: Linked to emotion processing, especially fear and aggression.

      • Hippocampus: Critical for forming and retrieving memories.

      • Hypothalamus: Regulates bodily maintenance activities (e.g., hunger, thirst, body temperature) and helps govern the endocrine system.

  • Cerebral Cortex:

    • Outer layer of the brain responsible for complex functions.

    • Divided into four main lobes:

      • Frontal Lobe: Involved in decision-making, planning, and voluntary movement.

      • Parietal Lobe: Processes sensory information (touch, spatial orientation).

      • Occipital Lobe: Responsible for visual processing.

      • Temporal Lobe: Processes auditory information and is involved in memory.

  • Split Brain:

    • Condition where the corpus callosum is cut, separating the brain’s hemispheres.

    • Leads to unique behaviors, like the inability to verbally identify objects seen only by the right hemisphere.

2. Tools for Examining Brain Structure and Function

  • EEG (Electroencephalograph):

    • Records electrical activity of the brain, often used to diagnose epilepsy, sleep disorders, and brain death.

  • CT (Computed Tomography) Scan:

    • Produces 3D x-ray images, useful for identifying brain injuries and tumors.

  • PET (Positron Emission Tomography) Scan:

    • Tracks glucose to measure activity in specific brain areas, often used in research on neurotransmitter function.

  • MRI and fMRI:

    • MRI: Generates high-resolution images by aligning hydrogen atoms, useful for structural analysis.

    • fMRI: Shows activity in real-time, useful for observing brain functions during tasks.

3. Brain Plasticity

  • The brain's ability to reorganize itself by forming new neural connections.

  • Neuroplasticity: Allows the brain to adapt after injury or in response to new experiences.

  • Important for rehabilitation, especially after strokes or traumatic brain injuries.

4. Sleeping and Dreaming

  • Sleep Cycles:

    • Each cycle lasts 60-90 minutes.

    • Early cycles are dominated by deep sleep (N3), while later cycles feature more REM sleep.

  • Sleep Stages:

    • Awake: Beta waves (alert) and Alpha waves (relaxed).

    • N1: Light sleep; marked by theta waves and hypnagogic sensations.

    • N2: Deeper stage with sleep spindles (bursts of activity) and K-complexes (high-amplitude waves).

    • N3: Deepest sleep, delta waves; important for body restoration.

    • REM: Rapid Eye Movement, vivid dreaming occurs, muscle atonia, brain waves resemble wakefulness.

  • Sleep Disorders:

    • Insomnia: Trouble falling/staying asleep.

    • Sleepwalking and Talking: Usually occur in N2 or N3.

    • Nightmares vs. Terrors: Nightmares in REM, night terrors in N3.

    • Narcolepsy: Sudden onset of REM sleep during the day.

    • REM Behavior Disorder: Acting out dreams, often linked to neurodegenerative disorders.

    • Sleep Apnea: Breathing interruptions; linked to cardiovascular problems.

    • Fatal Familial Insomnia: Rare genetic disorder leading to sleep loss, hallucinations, and eventually death.

5. Theories of Dreaming

  • Cognitive Theory:

    • Dreams reflect our thoughts, worries, and experiences.

  • Activation-Synthesis Theory:

    • Dreams result from the brain’s attempt to interpret random neural signals.

    • Cerebral cortex tries to create a coherent story.

  • Information Processing Theory:

    • Dreams may help us process memories and daily experiences.

  • Physiological Theory:

    • Brain activity in dreams might serve to develop or preserve neural pathways.

6. Endocrine System and Sleep Regulation

  • Pituitary Gland: The "master gland" regulated by the hypothalamus, affecting other glands.

  • Pineal Gland: Produces melatonin, which helps regulate sleep cycles.

Flashcards for Study Topics

Brain Areas and Functions

  1. Brainstem: Manages basic life functions.

  2. Medulla: Controls heartbeat and breathing.

  3. Pons: Aids in movement coordination, sleep, arousal.

  4. Reticular Formation: Controls arousal and alertness.

  5. Limbic System: Manages emotions and drives.

  6. Amygdala: Processes emotions, especially fear and aggression.

  7. Hippocampus: Responsible for memory formation and retrieval.

  8. Hypothalamus: Regulates hunger, thirst, body temperature, and hormones.

  9. Cerebral Cortex: Outer layer; controls complex functions.

  10. Frontal Lobe: Involved in decision-making, planning, and voluntary movement.

  11. Parietal Lobe: Processes sensory information.

  12. Occipital Lobe: Visual processing.

  13. Temporal Lobe: Auditory processing and memory.

  14. Split Brain: Result of severing the corpus callosum; separates hemispheres.

Tools for Brain Examination

  1. EEG: Measures brain’s electrical activity.

  2. CT Scan: 3D x-rays for brain structure imaging.

  3. PET Scan: Measures glucose use in brain areas.

  4. MRI: High-res structural images.

  5. fMRI: Real-time brain activity during tasks.

Sleep and Dreaming

  1. Sleep Cycles: 60-90 minutes, early = deep, late = REM.

  2. Stages of Sleep:

    • Awake: Beta waves.

    • N1: Light sleep, theta waves.

    • N2: Spindles and K-complexes.

    • N3: Deep sleep, delta waves.

    • REM: Vivid dreaming, brain resembles wakefulness.

  3. Sleep Disorders:

    • Insomnia: Difficulty sleeping.

    • Sleepwalking: Occurs in N2/N3.

    • Nightmares (REM) and Terrors (N3).

    • Narcolepsy: Sudden REM episodes.

    • REM Behavior Disorder: Acts out dreams.

    • Sleep Apnea: Breathing interruptions.

    • Fatal Familial Insomnia: Genetic, fatal.

  4. Dream Theories:

    • Cognitive: Reflects our thoughts.

    • Activation-Synthesis: Brain tries to make sense of random signals.

    • Information Processing: Dreams help process memories.

    • Physiological: Maintains neural pathways.

Endocrine System

  1. Pituitary Gland: Controls other glands, regulated by the hypothalamus.

  2. Pineal Gland: Releases melatonin, aiding sleep.

The thalamus acts as the brain's sensory relay station. It processes and transmits sensory information (except smell) to the cerebral cortex, directing signals for touch, vision, hearing, and taste to the appropriate areas of the brain for further processing. This central role makes it essential for sensory perception, attention, and consciousness.