brain science

Brain Science

Encompasses the study of the brain and nervous system, including structure, function, and diseases.

Traditional Disciplines in Brain Science

Includes neuroscience, psychology, biology, and medicine.

Applications of Brain Science

Clinical applications (diagnoses, treatment, and intervention)

Education and learning (neuroplasticity)

Productivity and focus (mindfulness)

Exercise and physical health

Sleep

Immune response, recovery, and pain management

Technology (ai, VR)

Neuro marketing

Advantages of Brain Science

Better treatment for neurological disorders.

Disadvantages of Brain Science

limited understanding

Individual differences

Brain is plastic

Challenges in Brain Science

Complexity of the brain, ethical considerations, and technological limitations.

Ethical Considerations in Brain Science

Privacy, consent, brain enhancement, and impacts on identity.

Advantages of Tools in Brain Science

Precise observation of brain functions

Availability .

EEG, MRI, PET

Disadvantages of Tools in Brain Science

Invasiveness, cost, and technical complexity. MRI IS EXPENSIVE A

Histological Techniques

Tools to look at cells

Nissl Stain

Allows you to look at cell bodies that exist in that tissue

Golgi Stain

Stains the entire neuron and the type of neuron

Immunohistochemistry

Tells you whether the cell is active or inactive

Tract Tracers

reveal the axonal projections of neurons

Brainbow

Reveals which neurons are communicating with one another

Neuron

The basic units of the nervous system

Specialized cells transmitting electrical signals throughout the nervous system.

General structure of neurons

Dendrites, cell body, axons, axon hillock, Myelin sheath, nodes of ranvier, axon terminals

Axon hillock

A cone shaped are of the cell body that gives rise to the axon

Axonal transport

the bidirectional movement of materials within an axon

Nodes of Ranvier

gaps in the myelin sheath.

Regenerates the action potential

Zones of Neurons

Input zone, integration zone, conduction zone, output zone

Input zone

Dendrites receive information from other neurons.

Integration zone

cell body (or soma) integrates information it receives

Conduction zone

single axon (or nerve fiber) conducts output information away from the cell body as an electrical impulse

Output zone

axon terminals at the end of the axon communicate activity to other neurons by releasing chemicals

Structural Classifications of Neurons

Multipolar, bipolar, unipolar neurons.

mulipolar neurons

One axon, many dendrites

bipolar neurons

one axon and one dendrite

unipolar neuron

a single extension branches in two directions, forming an input zone and an output zone

Functions of Sensory Neurons

Takes sensory information to the nervous system.

Has various shapes that responds best to environmental stimuli such as light, odor, or touch

Functions of Motor Neurons

Sends info out of the central nervous system

Has long axons and stimulates muscles .

Functions of Interneurons

Has tiny axons and analyzes input from one set of neurons and communicates with another

Nerve

A bundle of nerve fibers

components of synapse

presynaptic membrane, synaptic cleft, postsynaptic membrane

presynaptic membrane

on the axon terminal of the presynaptic nerve

Synaptic cleft

a gap that separates the membranes

postsynaptic membrane

on the dendrite or cell body of the postsynaptic neuron

Glial Cells

Support and protect neurons in the nervous system.

Oligodendrocytes

form myelin in central nervous system

Schwann Cells

Form myelin sheath in the peripheral nervous system

Astrocytes

Star shaped cells that stretch between neurons

Can help form the outer membrane around the brain .

microglial cells

Tiny mobile cells that remove micro dirt in cells

Cations

positively charged ions

Anion

A negatively charged ion

Action Potential

Rapid electrical signal traveling down the axon of a neuron.

Resting potential

the state of the neuron when not firing a neural impulse

Concentration of ions inside (intracellular) and outside (extracellular) of the cell

Ion channels

channel proteins that transport ions

Some channels are gated allowing K+ to pass but not sodium (N'a+)

selective permeability

Allowing K+ to pass but not sodium (na+) to nester or leave the cell freely

Diffusion

Causes ions to spread towards a uniform concentration (concentration gradient)

electrostatic pressure (voltage gradient)

Causes ions to flow towards oppositely charged areas

Depolarization

Decrease in the difference between the inside and outside of a neuron.

Hyperpolarization

Increase in the difference between the inside and outside of a neuron.

Sodium-Potassium Pump

Maintains resting potential by moving Na+ out and K+ into the cell.

Voltage-Gated Ion Channels

Open in response to changes in membrane potential to initiate action potentials.

Propagation

The spread of the action potential down an axon, caused by successive changes in electrical charge along the length of the axon's membrane.

All-or-None Property of Action Potential

Fires at full strength once threshold is reached or not at all.

Refractory Period

Time during which a neuron cannot fire another action potential.

Myelin's Effect on Action Potentials

Speeds up conduction by insulating the axon.

Saltatory Conduction

Action potentials jump between Nodes of Ranvier in myelinated neurons.

Postsynaptic Potentials (PSPs)

Changes in membrane potential of postsynaptic cell due to neurotransmitter release.

Excitatory and Inhibitory Postsynaptic Potentials (EPSPs and IPSPs)

EPSPs depolarize, while IPSPs hyperpolarize the postsynaptic membrane.

Temporal Summation

Summing of postsynaptic potentials from a single neuron over time.

Spatial Summation

Summing of postsynaptic potentials from different neurons at the same time.

Role of Calcium (Ca2+) in Chemical Signaling

Triggers neurotransmitter release from synaptic vesicles.

Neurotransmitter

Chemical substance transmitting signals across a synapse.

Types of Neurotransmitters

Amino acids, amines, peptides, and gas neurotransmitters.

Termination of Neurotransmitters

Through enzymatic degradation or reuptake into the presynaptic cell.

Endogenous and Exogenous Chemicals

Endogenous chemicals are naturally produced, while exogenous are introduced from outside.

Effects of Drugs on Neural Communication

Act as agonists (enhancing effects) or antagonists (blocking effects).

Hormones

Chemical messengers regulating body functions, secreted by endocrine glands.

Difference Between Hormones and Neurotransmitters

Hormones have widespread effects in the bloodstream, while neurotransmitters act locally at synapses.

Endocrine Glands

Glands releasing hormones directly into the bloodstream.

Axon

Which part of the neuron does the action potential propagate

Na+

Movement across voltage-gated channels primarily responsible for intiating an action potential

Hyperpolarization

Makes neron more negative and less likely to fire an action potential

Depolarization

Makes neron more positive and more likely to fire an action potential

Amino acids

GABA, glutamate

Amine neurotransmitters

cetylcholine, dopamine, serotonin, norepinephrine 

Glutamate

• most widespread excitatory transmitter

  • Likely to depolarize cell

Gamma-aminobutyric acid (GABA)

• most widespread inhibitory transmitter

  • Likely to hyperpolarize cells

Acetylcholine (ACh)

• Important for learning and memory

• Implicated in Alzheimer’s disease