Anatomy and Physiology: Sleep, Emotions, LanguageMemory, Cognition,

What does an EEG measure?

brain activity in “wave forms”. Wave forms are the ebbs and flows in the charts. EEGs detect EPSP and wave frequencies.

What are the wave patterns seen on an EEG?

• alpha waves: awake or relaxed

• beta waves: awake, alert (increased freq.)

• theta waves: dozing off (decreased freq. with decreased amplitude)

• delta waves: deep, NOT REM, sleep (decreased freq. increased amplitude)

What are characteristics of REM sleep?

• dreams

• a lot of theta wave activity

• active limbic system

• for most people, their muscles are paralyzes so they can’t move

  • though in some people, this system isn’t 100% or doesn’t work at all so they act out their dreams.

What are characteristics of nREM sleep?

has 4 subdivisions:

• N1: theta waves, easily awakened (dozing off)

• N2: deep sleep; most of the time spent sleeping is spent in the N2 stage. Temperature and heart rate decrease

• N3/N4 deepest stages, tissue repair/regrowth, nightmares

What are the states of unconsciousness?

• sleep: can be woken up/ decreased consciousness

• fainting/coma: can’t be woken up with painful stimuli

• persistent vegetative state

What are the structures that assist with sleep and sleep cycles?

• Reticular activating system: transitions between awake and sleep

• Hypothalamus: starts sleep, sleep duration

• Hippocampus: memories and dreams

• Amygdala: dreams

• Thalamus: influences brainwaves

• Pons: REM sleep

Why do we need sleep?

• neural growth (mainly in childhood)

• learning and memory

• declutters unneeded synapses

• conserve metabolic energy

What are the types of biological rhythms?

• Circadian rhythm: controls release of melatonin, cortisol and ACTH

• Phase shift rhythm: shift body clock to align with a new schedule or time zone etc.

What area of the brain contains pacemaker cells that control our circadian rhythm?

Hypothalamus. It releases melatonin which makes us sleepy

How does the presence of light influence our sleep cycles?

Photoreceptors in our eyes respond to different kinds of light. Blue light stimulates and DEGRADES melatonin, which in turn wakes us up. Yellow light makes us sleepier.

A typical sleep cycle lasts about 90 minutes and most people go through 5ish cycles a night. Though sometimes, a cycle doesn’t include all the non-REM stages because they start to “run together” where like N2-N4 just kinda become one stage.

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What neurotransmitters are needed for wakefulness?

• decreased GABA

• increased Histamine

• increased serotonin (excitatory; specifically promotes wakefulness)

What neurotransmitters are needed for nREM sleep?

• increased GABA

• decreased Histamine

• Glycine: inhibits motor neurons

What neurotransmitters are needed for REM sleep?

• decreased norepinephrine (excitatory)

• increased Ach

• Glycine

• decreased Serotonin

What brain structures are involved in making memories?

• amygdala

• thalamus

• hippocampus

• temporal lobe

How does the temporal lobe help with memory formation?

• long-term visual memories

• memory association (relating 2 unrelated things like an unfamiliar name with a face) and emotional responses

What are the types of memories?

• working/short-term memory

• long-term

What are the ways of remembering things that happened recently (short-term)

• chunking: grouping info into smaller sets (phone numbers, SSN)

• chaining: relating items by developing a story

What is long term-memory and how is it accomplished?

Long term memory is the consolidation of short-term memory from storage. There are physical changes in the brain to accommodate long-term memory. This process takes days to year, but there is an unlimited capacity for how much info our brain can remember.

What are the types of long-term memory?

• nondeclarative: memories of basic skills (riding a bike, dressing ourselves)

• declarative: memory can be verbalized

  • semantic: facts (like remembering all the bones of the body)

  • episodic: events (taking the 2nd lab practical)

What is the process of memory consolidation?

• there is permanent chemical structural change or change in the synapse

• synapse is stimulated by an increase in frequency (which means an increase in excitability of the neuron)

• the synapse or dendrites can change in shape (produces more proteins??)

• more synapses can be created

• more NTs are released

  *these are in no particular order

What are the types of amnesia?

• anterograde: can’t recall recent past events. has trouble making new memories

• retrograde: can’t recall old info or info before the trauma

• Transient global amnesia: can’t remember stuff from a few minutes ago, the condition resolves within 24 hours