Transcript The Brain and Its Disorders

The Brain and Its Disorders
The Brain and Its Disorders
The Brain
How To Study the Brain
Psychopathologies
Amnesias, Language Disorders, and
Prosopagnosia
The Neuron
The Neuron
• The brain’s most basic functional unit
The Neuron
Soma
Dendrites
Myelin
Sheath
Axon
Axon
Terminals
The Neuron
• Soma (cell body) – contains nucleus,
cytoplasm, organelles
• Dendrites – receive info
• Axon – transmits info
• Myelin sheath – covers the axon to
increase transmission speed (cause of
sensory and motor disturbances in
multiple sclerosis)
Action Potentials
Action Potentials
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How neurons transfer info
Changes neuron’s membrane potential
Rising phase – membrane depolarizes
Overshoot
Falling phase – membrane repolarizes
Undershoot
Restoration of resting potential
Neurodegeneration
• Involved in disorders like Alzheimer’s,
Huntington’s, Parkinson’s
The Synapse
The Synapse
• Axon terminal
releases
neurotransmitters
• Neurotransmitters
cross the synapse
and bind to receptors
on another neuron
• Neurotransmitters
released, taken up
again by first neuron
Neurotransmitters
• Acetylcholine – movement (respiratory paralysis)
• Serotonin – mood, sleep, appetite, anxiety
(depression, obsessive-compulsive disorder,
panic disorder)
• Dopamine – motivation, pleasure
(schizophrenia, Parkinson’s)
• Epinephrine and Norepinephrine – attention,
anxiety, stress (epilepsy, mania in bipolar
disorder)
Neuropharmacology
Reuptake Inhibitors
• Prevent reuptake of neurotransmitters
from the synapse
• Selective serotonin reuptake inhibitors
• Example: Prozac
– Treats depression, OCD, panic disorder
The Blood-Brain Barrier
The Blood-Brain Barrier
• Endothelial cells in blood vessels in the
brain fit closely together
• Only some molecules can pass through
• Protects the brain from foreign molecules
and hormones and neurotransmitters from
other parts of the body
• Can be damaged by infections, head
trauma, high blood pressure, etc.
The Brain
The Brain
The Brain
• Cerebral Cortex – thought, language,
reasoning, movement, sensation
• Corpus Callosum – connects the right and
left hemispheres
• Cerebellum – movement, balance
• Brainstem – breathing, heart rate
Lobes of the Brain
Lobes of the Brain
• Frontal Lobe – personality, planning,
emotion, problem solving
– Motor cortex - movement
– Broca’s area – speech production
• Parietal Lobe - touch
• Temporal Lobe – hearing
– Inferotemporal Cortex – object recognition
– Wernicke’s area – language comprehension
• Occipital Lobe - vision