Brain Facts - Neuroscience Vocabulary Flashcards

Vocabulary flashcards covering key neuroscience concepts, neuroanatomy, brain functions, cellular mechanisms, and physiological processes based on the Brain Facts guide.

Corpus Callosum

The largest bundle of nerve fibers in the brain that forms a bridge connecting the left and right cerebral hemispheres, transferring information between them.

Lobes of the Cerebral Cortex

The four principal functional subdivisions of the cerebral cortex: the frontal lobe (attention, planning, decision-making, motor control), temporal lobe (language, memory, emotion), parietal lobe (sensory integration), and occipital lobe (visual processing).

Hippocampus

A curved structure located beneath the cerebral cortex within the temporal lobes that plays a critical role in encoding new memories and spatial navigation.

Amygdala

A paired, almond-shaped structure located within each temporal lobe that integrates memory and emotion, particularly modulating fear and fight-or-flight responses.

Basal Ganglia

A group of interconnected deep-brain structures—including the caudate nucleus, putamen, nucleus accumbens, globus pallidus, and substantia nigra—that helps regulate voluntary body movements and habit formation.

Cerebellum

The second-largest part of the brain by volume, located underneath the occipital lobe, which coordinates voluntary movements, aids in learning motor skills, and assists in spatial and temporal perception.

Brainstem

The region at the base of the brain connecting the forebrain to the spinal cord, composed of the midbrain, pons, and medulla, which regulates basic life functions like breathing, heart rate, and swallowing.

Alpha Waves

Brain waves with frequencies between $8$\text{ and }$13\,\text{Hz}$ originating mainly in the parietal and occipital lobes when the brain is relaxed with eyes closed.

Beta Waves

Brain waves with frequencies ranging from $14$\text{ to }$30\,\text{Hz}$ produced by the frontal and parietal regions during active sensory processing or concentration on a task.

Pyramidal Cell

The most common type of excitatory neuron in many parts of the cerebral cortex, named for its cone-shaped cell body, featuring two sets of branched dendrites and a multi-branched axon.

Astrocytes

Star-shaped glial cells in the central nervous system that regulate ion concentrations around neurons, provide nutrients, form the blood-brain barrier, and aid in synapse formation and pruning.

Microglia

The primary immune cells of the brain that function as phagocytes to protect against infection and cellular damage, as well as assist in regulating synaptic connections.

Oligodendrocytes

Glial cells in the central nervous system that improve neuronal signaling speed by wrapping axons in a fatty sheath called myelin.

Glutamate

The primary excitatory neurotransmitter in the brain, utilized by approximately half of all excitatory synapses and binding to AMPA and NMDA receptors.

GABA (Gamma-Aminobutyric Acid)

The primary inhibitory neurotransmitter in the brain that acts to hyperpolarize postsynaptic membranes and suppress neuronal firing.

Visual Pathway

The neural route of visual processing, wherein light passes through the lens to the retina, generating electrical signals that travel via the optic nerve and optic chiasma to the lateral geniculate nucleus (LGN) of the thalamus and on to the primary visual cortex.

Fovea

A small pitted area in the center of the retina containing only densely packed red and green cones, providing the highest visual acuity.

Strabismus

A condition characterized by crossed or misaligned eyes, preventing proper fusion of visual inputs from both eyes and reducing 3D depth perception.

Basilar Membrane

An elastic membrane running along the inside of the cochlea that is tuned along its length to different frequencies, moving in response to sound waves to stimulate hair cells.

Nociceptors

Specialized sensory nerve fibers that respond to high-threshold, potentially tissue-damaging thermal, mechanical, or chemical stimuli to signal pain.

Allodynia

A condition in which normally harmless touch produces pain due to heightened receptor sensitivity after tissue injury, such as on sunburned skin.

Neuropathic Pain

A long-lasting state of pain hypersensitivity caused by a malfunctioning or damaged nervous system rather than an active tissue injury.

Motor Unit

The functional unit of skeletal muscle control, consisting of a single alpha motor neuron and all the individual muscle fibers it innervates.

Declarative Memory

The form of long-term memory for facts, data, and events that can be consciously recalled and described, divided into semantic and episodic memory.

Long-Term Potentiation (LTP)

A persistent increase in synaptic strength characterized by an increased number of postsynaptic glutamate receptors, essential for long-term memory consolidation.

Broca's Area

A region in the left frontal lobe vital for speech production; damage here causes non-fluent aphasia characterized by slow, halting speech.

Wernicke's Area

A region in the left temporal lobe crucial for speech comprehension; damage here causes fluent aphasia where speech sounds normal in speed but lacks coherent meaning.

Radial Glia

Specialized glial cells projecting radially from the intermediate zone to the cortex that serve as scaffolding for migrating newborn neurons during embryonic development.

Apoptosis

Programmed cell death that naturally eliminates roughly half of the neurons produced during development if they fail to receive sufficient trophic factors.

Plasticity

The brain's ability to modify its neural connections, structure, and function in response to experience, learning, or environmental challenges.

Suprachiasmatic Nucleus (SCN)

A small group of neurons in the hypothalamus that functions as the master clock for the body, coordinating 24-hour circadian rhythms.

Melatonin

A hormone secreted into the bloodstream by the pineal gland at night in response to SCN activity, reducing alertness and inducing sleepiness.

Ghrelin

A hormone released by the wall of the gastrointestinal tract when the stomach is empty that activates hunger circuits in the hypothalamus.

Leptin

A hormone produced by fat cells that binds to hypothalamic neurons to suppress hunger circuits when body fat stores are sufficient.