Brain Structure and Functions

Study Notes

The brain is the central control centre for the central nervous system, overseeing complex functions like thought, memory, emotion, and voluntary action.
It comprises distinct regions with specialized roles.
The brain is protected by the skull, meninges (protective membranes), and cerebrospinal fluid.
Grey matter, containing neuron cell bodies, is concentrated in the cortex and other areas.
White matter, made of myelinated axons, connects different brain regions.
The brain is divided into the cerebrum, cerebellum, and brainstem.

The cerebrum, the largest part of the brain, is responsible for higher-level cognitive functions.
It is divided into two hemispheres (left and right), connected by the corpus callosum.
Each hemisphere is further divided into four lobes: frontal, parietal, temporal, and occipital.
The frontal lobe is vital for planning, decision-making, and voluntary movement.
The parietal lobe processes sensory information, including touch and spatial awareness.
The temporal lobe is involved in auditory processing, language comprehension, and memory.
The occipital lobe primarily processes visual information.

The cerebellum is located beneath the cerebrum, coordinating movement, balance, and posture.
It refines and smooths movements, receiving information from the cerebrum and other nervous system parts.

The brainstem connects the brain to the spinal cord.
It controls vital life functions like breathing, heart rate, and blood pressure.
It consists of the midbrain, pons, and medulla oblongata.

Neurons are the brain's fundamental units, transmitting signals electrically and chemically.
Glial cells support and insulate neurons, playing a critical role in brain function.
Myelin sheaths, fatty insulating layers around axons, accelerate signal transmission.

Neurotransmitters are chemical messengers transmitting signals between neurons.
Examples include dopamine, serotonin, glutamate, and GABA, essential for many brain functions.

Brain activity is measured using techniques like EEG (electroencephalogram), fMRI (functional magnetic resonance imaging), and PET (positron emission tomography).
EEG measures electrical activity, fMRI tracks blood flow changes, and PET measures metabolic activity.

Brain development is a complex process throughout childhood and adolescence.
It involves forming new neurons, connections between neurons, and myelination of axons.
Environmental factors and genetics are crucial aspects of brain development.