CH 2: Neurobiology (AP PYSCH)

Neurons

sends/recieves signals and controls motor/behaviors

Soma

the body of neuron

dendrites

recieves info from other neurons

axon

conducts fibers and passes messages to other neurons or muscles

terminal branches

connection to other neurons/cells

Resting potential

charge is separated by membrane of neuron (“Potential” to do work)

Threshold

the level of excitatory neurotransmitters that a neuron must absorb before it will fire

Action Potential

Electrical events that begins when neuron reaches threshold (opening the flap in the tank and water flowing through)

Depolarization

when the inside of the cell becomes more positively charged (toilet flushing)

Unidirectional flow

from soma to axon (Toilet flushes only one way)

All or None Principle

doesnt matter if there is little enery, or a lot and the neuron always fires at the same intensity

Sodium-Potassium Pump

channel that regulates the charge for resting state, potassium and sodium can leak out

Refractory Period

neuron must recharge before it can fire again.

Neurotransmitter

chemical messenger between neurons and released following an action potential

Synaptic Gap AKA Synapse AKA Synaptic Cleft

junction (tiny gap) between neurons , where neurons communicate with each other

Vesicles

sacks in terminal buttons and store neurotransmitters

Receptors

on dendrite: neurotransmitters attach and transmit message

what is the difference between exitatory and inhibitory?

excitatory makes the neuron fire while inhibitory revents firing

Reuptake

reabsortion of neurotransmitters back into the axon of the sending neuron

Reflex

impulse conduction over a few neurons

Sensory <afferent> neurons

impulses from sensory receptors to Spinal Cord/Brain and approaches the brain /incoming info

Motor (Efferent) Neurons

sends info to muscles and gland (Exits the brain) and outgoing info

Interneuron

located in brain/spinal cord and is the in-between messenger responsible for reflexes

Peripheral Nervous System (PNS)

mostly OUTSIDE of brain and spinal cord and carries sensory & motor signals to/from CNS. consist of Somatic NS & Autonomic NS

Somatic Nervous System

nerves for skeletal muscles and control system for our VOLUNTARY MUSCLES (conscious)

Autonomic Nervous System

UNCONSCIOUS , nerves for glands & muscles and consist of sympathetic & parasympathetic NS

Sympathetic NS

arouses to deal with stress, “fight or flight”

Parasympathetic NS

calms to return to homeostasis

The Subcortex

the CENTER of lower-level processes (BASIC stuff) and includes the hindbrain & midbrain

What does the Hindbrain consist of?

it consists of the medulla, pons, and cerebellum

Medulla oblongata

part of the brain stem and has autonomic functions (ex: heart rate, blood pressue)

The Pons

part of brain stem and helps coordinate automatic facial movement and regulates SLEEP-WAKE CYCLE & AROUSAL

Cerebellum

coordinates balance & posture and stores IMPLICIT (muscle) memory (VOLUNTARY MOVEMENT)

The Midbrain

integrates sensory progresses and controls involuntary muscle tone

Reticular Formation (AKA Reticular Activating System)

it keeps you awake, Arousal/Attention

Thalamus

audio, visual, and somatosensory (touch, helps recognize objects)

Hypothalamus

controls hunger/thirst, body temperature, sex drive and controls FIGHT OR FLIGHT (nemonic: the five f’s: flight, fight, feeding, fluids, f-ing)

Pituitary Gland

connected to hypothalamus and releases growth hormones to regulate physical development (the MASTER gland)

The Limbic System

motivation, emotion, and memory

Hippocampus

memory formation and explicit info (episodic=personal & semantic= facts/meaning)

Amygdala

processes info w/ emotional content (eg; facial expressions) and triggers anger, aggression& fear

Cerebrum

part of the forebrain and largest part of brain which contains complex mental activities

Cerebral Cortex

The center of higher-level processes and executive function includes conscious awareness

Corpus Callosum

Large band of axons that communicate between left and right hemispheres

What are the 4 forebrain Structures?

Frontal, Sensory (Parietal), Occipital, and Temporal

Frontal Lobes

consist of pre-frontal, pre-motor, and motor cortex’s

Pre-frontal Cortex

personality, processing of emtions, abstract thought, logic, judgement/planning

Pre-motor cortex

FINE (small) motor skills

Motor Cortex

speech production & gross (large) muscle movement , mapped for all muscle movement

BROCA’s Area

left hemisphere and controls expressive language

Broca’s aphasia

damage in speech production and selection of words (slow and inarticulate)

Sensory Cortex

front of parietal lobes and mapped for all skin sensations

Auditory Cortex (temporal lobes)

center of processing for hearing

Wernicke’s Aera (temporal lobes

left= language, understanding speech sounds and works with. BROCAS AREA

Right temporal lobes

recognize faces

Occipital lobes

above cerebellum and contains visual cortex and association areas

Association Areas

network with the whole cerebrum and mid-brain to form complex thoughts

lesions

destroy brain tissue, usually animals

autopsy

after death examination

EEG (electroencephalogram)

direct contact with scalp and transmits activation of neurons, only surface level (sleep/dreaming, abnormalities in infants)

CAT Scant (CT)

2D “Slices” of X-Rays, show extent of a lesion and faster than MRI

MRI (magnetic resonance imaging)

picture of organs, more detailed than CAT or PET (for brain tumors)

PET Scan

scan shows where neurons are active, exposed to radioactivity

fMRI (Functional MRI)

reveals brain function & activity over time and there is no radio activity (video)

MRI

photo of organs and shows size/structure

Corpus Callosum

normally allows integration of information between both hemispheres as it happens

Sperry’s Epilepsy patients

split brain research (Gazzaniga), found out that hemispheres had different but complimentary functions

Left Hemisphere of Brain

verbal processing; speech, reading, writing

Right Hemisphere of Brain

nonverbal processing; spatial, musical, and visual recognition, facial recognition

Plasticity

the ability for our brains to form new connections after the neurons are damaged or removed

neurogenesis

formation of new neurons

Endocrine System

pairs with hypothalamus > sympathetic & parasympathetic systems

whats the difference between hormones and neurotransmitters

hormones are secreted into bloodstream and have a slow transportation. while neurotransmitters are released in neural network and transport in seconds.