Psychology 12 Brain

Neuron

Cells that have specialized extensions for the reception and transmission of electrical signals.

Motor neurons

Send messages from the brain to the muscles, organs and glands Also know as Efferent Neuron. Helps your brain complete task and do actions.

sensory neurons

Carries information from our sense(vision, taste, smell, pain, hearing, touch) receptors to the spinal cord and up to brain. Also known as Afferent Neurons

Dendrite

Branchlike extension that arise from the cell body; they receive signals from other neutrons. Front of the Neuron, the receiver. Made out of fibres.

Soma/cell body

Keeps the cell working properly and maintains the cell health. Analyzes messages the cell receives and passes on the appropriate information to the axon.

Nucleus

The control center of the neuron, housing the cell's genetic material and important for cell growth/maturing.

Axon

A long, thin structure that transmits electrical impulses away from the cell body to other neurons or muscles. It is often covered by myelin to speed up signal transmission.

Synapse

The places where neurons connect and communicate with each other are called synapses.

End bulbs (axon terminal)

End of the neuron • Produces & releases neurotransmitters into the synaptic gap. • Electrical message converted to chemical messaging to transmit signals to other neurons.

Myelin sheath

Protective coating of the axon and helps insulates the electric signal

Neurotransmitter/ cell body

the chemical message (neurotransmitters) floats across the synaptic gap to other neurons

Receptor sites

Helps receive information top of dendrites

• Respond to the information by triggering a specific action in the cell

• Regulate the amount and type of information that gets through

• Interpret the information and help the cell make decisions

Think of receptor sites like a messenger service:

• They receive messages (chemicals)

• They decode the message and figure out what it means

• They respond to the message by triggering a specific action in the cell

Action potential

Electrical signal traveling down the axon

Refractory period

a period of time during which a cell is incapable of repeating an action potential

Re-uptake

Re-uptake is when neurotransmitters (chemical messengers) are absorbed back into the neuron that released them.

Cerebral cortex

is the outermost layer of the brain, responsible for processing sensory information, controlling movement, and facilitating thought, perception, and memory. (outer skin of the brain)

• Share info

• Connected to each hemispheres the fibers connecting the two halfs

• Transfer of sensory, motor and cognitive info

Plasticity

Neuroplasticity refers to the brain's ability to reorganize, adapt, and change throughout life in response to new experiences, environments, and learning.

• ability of the brain tissue to take on new functions or recover lost functionality.​

• Reorganization of neural pathways​

• The greatest in childhood reduces as you age​

• Repair damage or slow the weakening of the brain​

Left brain specialization

Speech, Symbolic thinking​

• Language​

• Detail​

• Analysis​

• Math/numbers​

• logic/reasoning​

• Problem solving​

• Right side control

Right brain specialization

Controls life side of the body

• Spatial perception​

• Organization​

• Creativity​

• Music​

• Emotions & relationships​

• Face recognition​

• Left side control

Reuptake

Reabsorbs the information sent

the process by which a brain cell "takes back" a chemical messenger (neurotransmitter) after sending a signal, regulating its amount and strength.

all-or-none principle

the axon either “fires” or it does not similar to a gun

The same level of electricity is utilized independent of the intensity of the stimulus. • How do we detect a gentle graze from a stubbing our toe? • A strong stimulus, like hitting our foot hard, can trigger more neurons to fire, more often, but not any stronger.

MRI (Magnetic resonance imaging)

• display anatomic structure in high-resolution

• Helps to find & diagnose brain abnormalities​

• Uses magnetic fields and radio waves to produce detailed images of the brain’s soft tissue. ​

• Non-invasive, no radiation way to examine organs, tissues, brain & skeletal system

• Used for: structural imaging, injuries, cancers, neurological disorders

provide information about structures and tissues at one point in time.

Electroencephalography (EEG)

• measures brain waves​

• Measures brain electrical activity

• Non-invasive, painless

• electrodes detect electrical activity in the brain and the computer creates a graph-like image. ​

• In real time

EEG can detect issues such as:​ anxiety, head injuries, epilepsy, sleep disruption

fMRI (Functional MRI)

• shows the physical structure, activity, and function of the brain in real time.​

• determine which part of the brain controls thought, speech, movement and sensation (brain mapping)​

• The patient interacts with stimuli during the scan to show that activity​

• Measures brain activity, blood flow, and oxygenation in the brain​

• Non-invasive, no radiation

• Used for: brain function, cognitive processes, neural activity

PET (Positron Emission Tomography)

• uses a small amounts of radioactive form of glucose(sugar) to visualize brain function​

• As your brain/body uses the glucose, the scanner shows areas of varying intensity depending on brain activity.​

• Can see trouble spots where glucose isn’t moving correctly.​

• Minimally invasive, low radiation

• PET scans can evaluate:​ seizures​, Alzheimer’s​, tumors

Computerized Tomography (CT)

• Uses X-rays to produce detailed images

• combined to form cross-sectional slices or 3-D models of the brain.​

• provide more detail than a standard X-ray.​

CT scans can:​

• find certain types of brain injuries​

• identify cancer​

• locate brain swelling or bleeding​

• reveal structural brain changes from schizophrenia​

MEG (Magnetoencephalography)

• measures the magnetic field from neuron activity. ​

• can locate & identify malfunctioning neurons in your brain.

• Measures magnetic fields generated by brain electrical activity​

MEG can help to assess:​

• epilepsy sources​

• motor areas​

• sensory areas​

• language and vision​

Glial Cells

Helper cells in the brain and nervous system that:

• Keep neurons healthy

• Provide nutrients and oxygen

• Remove waste

• Insulate and protect neurons

• Help fight infections

Think of glial cells like the pit crew for neurons, keeping them running smoothly and efficiently!