Biopsych Unit 1

memory formation steps

stimulus → short term memory → consolidation/active memory → long term memory → reconsolidation → long term memory

issue with reconsolidating

vulnerable to deletion and altering of memory

propanolol (definition, two ways it affects memories)

• beta-blocker that helps delete traumatic parts of memories, works during recall

• 1: traumatic situation just happened and blocks consolidation (more common)

• 2: traumatic memory actively being recalled, blocks reconsolidation

dualism

mind and body work independently

Descartes

mind & body consciousness interacts through the pineal gland

phrenology

localization of function in the brain

fMRI

measures blood-oxygen-level-dependent signals to measure neural activity (indirectly)

EEG

measures electric waves, temporal neural activity, electrodes

PET

uses radioactive drugs to measure active brain processes by emitting positrons

physical damage and localizing function

• stroke, aphasia, physical trauma

• pinpoints damage to see what parts of the brain correspond to different types of trauma

Phineas Gage

• orbitofrontal regions, prefrontal cortex

• impulse control, executive function

Darwin & natural selection

traits that helped isolated specie survive contributed to speciation

• traits more prominent with each generation

Gregor Mendel (father of genetics)

described pattern of inheritance with physical traits

• punnet squares

• pea plants

• no polygenetic traits

central dogma

DNA → RNA → proteins → altered excitability of neurons → influenced behavior

proteins and examples (4)

long sequence of amino acids that folds in on itself to make different structures and carry out different functions

• enzymes

• receptors

• transporters

• structural elements of cells

phenylalanine

• make tyrosine

• when too much, makes phenylpyruvate (toxin)

• prevents amino acids from being transported to the brain to make proteins

genome-wide association studies & Manhattan plot

measures how an excess of genes within each chromosome is associated with the prevalence of a polygenetic disorder

parts of the neuron (7)

• dendrite

• soma

• axon hillock

• axon

• myelin sheath

• node of Ranvier

• terminal

types of neurons and where they are

• multipolar (nervous system)

• bipolar (sensory system)

• unipolar (invertebrates central nervous system)

ways to visualize neurons (4)

• immunocytochemistry (detects antigens in cells using light microscopy)

• brain slices

• Nissl stain (staining DNA and RNA)

• Golgi stain (staining individual neurons)

4 types of glia

• oligodendrocytes: makes myelin sheath in CNS, around several axons at once

• Schwann cells: makes myelin sheath in PNS, around only one axon at a time

• astrocytes: most abundant glia, supports and protects neurons, wraps around endothelial cells in BBB

• microglia: engulfs and destroys debris in CNS

purpose of myelin sheath

protects and insulates axons, speeds up electrical signals through CNS

saltatory conduction

when the signal hops from node of ranvier to node of ranvier, flows due to opening of voltage-gated sodium channels

blood-brain barrier

semipermeable barrier that restricts access to neurons through junctions between endothelial cells in blood vessels and astrocytes. freely allows oxygen, CO2, & fat-soluble molecules w/o active transport. uses astrocytes.

why weak BBB could be advantegous

life-saving drugs and targeted therapies can bypass the barrier and reach the neurons

demyelination

breakdown/loss of protective myelin sheath, can happen when immune system targets and gets rid of the myelin sheath, which is called multiple sclerosis, disrupts saltatory conduction