the brain, biology, and behaviour

Neuron

A cell that sends and receives information/messages

Dendrites

Receive messages from other neurons

Soma

The cell body; keeps the neuron alive (contains DNA)

Axon

Carries the electrical signal away from the soma (send messages)

Myelin

Insulates the axon and speeds up neural signals (fatty substance that protects Axon)

Terminal

Release neurotransmitters into the synapse (entry and exit)

Synapse

Gaps between neurons

Neurotransmitters

THE chemical messenge being send by neutrons

Sensory neuron

(Afferent) body→brain (input)

Motor neuron

(Efferent) brain→body (output)

Interneuron

Connects neurons within the CNS (carry information between each other brain and spinal cord)

Glial cells

Support, protect, and nourish neurons (“glue” that holds all neurons in places and provide them with nutrients)

Action potential

A brief electrical impulse traveling down an axon

Threshold

The level of stimulation needed to trigger a neural impulse

Resting potential

The neuron's electrical charge when it is not firing

Depolarization

When sodium ions rush into the neuron as it fires

Repolarization

When the neuron returns toward its resting charge

Refractory period

A brief reset period when the neuron cannot fire normally (potassium-in, sodium-out)

All-or-none principle

A neuron either fires completely or does not fire

Stronger stimulus

Does NOT make one action potential stronger; it can cause neurons to fire more often or recruit more neurons

Excitatory

Makes a neuron more likely to fire

Inhibitory

Makes a neuron less likely to fire

Reuptake

Reabsorbing leftover neurotransmitters back into the sending neuron

Acetylcholine (ACh)

Involved in muscle movement, learning, and memory. If ACh is decreased-memory is impaired.

Dopamine

Involved in pleasure movement, reward, and motivation; PHYSICAL feeling. Schizophrenia- too much dopamine. Parkinson’s-low dopamine.

Serotonin

Involved in mood, sleep, and appetite (job→keeps u happy); low amounts→depression; high amounts→manic

Norepinephrine

Acts as a natural painkiller (morphine)

Endorphins

Natural pain-relieving chemicals

GABA

A major inhibitory neurotransmitter that slows neural activity

Glutamate

A major excitatory neurotransmitter involved in learning

Substance P

Neurotransmitter involved in pain signaling

Agonist

A substance that increases or mimics a neurotransmitter's effects

Antagonist

A substance that decreases or blocks a neurotransmitter's effects

Multiple sclerosis (MS)

A disease that damages myelin, slowing neural communication

Myasthenia gravis

A disorder involving problems with acetylcholine communication, causing muscle weakness

Central nervous system (CNS)

The brain and spinal cord

Peripheral nervous system (PNS)

All nervous system parts outside the brain and spinal cord

Somatic nervous system

Controls voluntary movements of skeletal muscles

Autonomic nervous system

Controls automatic/involuntary functions

Sympathetic nervous system

Activates the fight-or-flight response

Parasympathetic nervous system

Calms the body and supports rest-and-digest functions

Phineas Gage

A famous brain-injury case showing that damage to certain brain areas can affect behavior and personality

Hindbrain

Includes the pons, medulla, cerebellum, and reticular formation

Pons

Helps regulate sleep, breathing, and communication between brain areas

Medulla

Controls important automatic functions such as breathing and heart rate

Cerebellum

Helps with balance, coordination, and fine motor movement

Reticular formation (RAS)

Helps control alertness and arousal

Forebrain

The major upper region of the brain involved in complex thinking, emotion, memory, and sensory processing

Cerebral cortex

The outer layer of the brain involved in higher-level thinking and processing

Corpus callosum

A bundle of nerve fibers connecting the left and right hemispheres

Left hemisphere

Generally specializes more in language and analytical processing

Right hemisphere

Generally specializes more in spatial and visual processing

Split-brain

A condition in which the corpus callosum has been severed, limiting communication between the hemispheres

Frontal lobe

Involved in planning, decision-making, personality, and voluntary movement

Parietal lobe

Processes touch and other body sensations

Temporal lobe

Involved in hearing, language, and memory

Occipital lobe

Processes visual information

Motor cortex

Controls voluntary movements

Sensory cortex

Processes touch and other body sensations

Broca's area

Brain area involved in producing speech

Wernicke's area

Brain area involved in understanding language

Aphasia

Difficulty with language caused by brain damage

Broca's aphasia

Difficulty producing speech, while understanding may be relatively better

Wernicke's aphasia

Difficulty understanding language; speech may be fluent but not make sense

Limbic system

Brain system involved in emotion, motivation, and memory

Amygdala

Involved in emotion, especially fear and emotional responses

Hippocampus

Important for forming and storing new memories

Hypothalamus

Helps regulate hunger, thirst, body temperature, hormones, and homeostasis

Thalamus

Relays most sensory information to the appropriate areas of the brain

Plasticity

The brain's ability to change and reorganize itself

Neurogenesis

The creation of new neurons

Endocrine system

A system of glands that releases hormones into the bloodstream

Hormones

Chemical messengers released by endocrine glands into the bloodstream

Pituitary gland

Helps control many other endocrine glands and hormone functions

Adrenaline

Hormone that increases arousal and prepares the body for fight-or-flight

Oxytocin

Hormone involved in bonding, childbirth, and breastfeeding

Melatonin

Hormone involved in regulating the sleep-wake cycle

Leptin

Hormone that signals fullness and helps regulate hunger

Ghrelin

Hormone that increases hunger

Lesioning

Intentionally damaging or studying damaged brain tissue to learn what a brain area does

MRI

Uses magnetic fields and radio waves to create detailed images of brain structure

CT scan

Uses X-rays to create images of brain structure

PET scan

Measures brain activity by tracking glucose use

EEG

Measures electrical activity in the brain

Twin studies

Nature VS Nurture (genetics vs environment)

Epigenetics

How the environment can manipulate/ulter genes