Biological basics terms

All terms to try and memories.

Aδ Fiber

A type of nerve fiber that is thinly myelinated and conducts action potentials at speeds of 5–30 m/s. Responsible for transmitting sharp, well-localized pain sensations and are sensitive to mechanical and thermal stimuli.

Acupuncture

A traditional Chinese medicine practice involving the insertion of thin needles into specific points on the body. Believed to stimulate the nervous system and may influence pain perception and other physiological processes.

Adaptation

The process by which sensory receptors become less responsive to a constant stimulus over time. Allows the nervous system to focus on changes in the environment rather than constant stimuli.

Adequate Stimulus

The specific type of stimulus to which a sensory receptor is most sensitive. For example, photoreceptors are sensitive to light, while mechanoreceptors respond to mechanical pressure.

Analgesia

The absence or reduction of pain perception. Can be achieved through various means, including pharmacological agents, acupuncture, or psychological techniques.

Anterolateral System

A neural pathway that transmits pain and temperature information from the spinal cord to the brain. It includes the spinothalamic tract and other related pathways.

Attention

The cognitive process of selectively focusing on specific information while ignoring other stimuli. Can modulate pain perception.

C Fiber

Unmyelinated nerve fibers that conduct action potentials slowly (0.5–2 m/s). Responsible for transmitting dull, aching, or burning pain sensations and are sensitive to thermal, mechanical, and chemical stimuli.

Cannabis

A plant known for its psychoactive properties, primarily due to compounds like THC. It has been studied for its potential analgesic effects.

Capsaicin

The active compound in chili peppers that produces a burning sensation. It activates the TRPV1 receptor, which is involved in the sensation of heat and pain.

Cingulate Cortex

A region of the brain involved in processing emotions and pain. It plays a role in the affective component of pain perception.

Coding

The process by which sensory information is transformed into neural signals that can be interpreted by the brain. This involves the activation of specific neural pathways and receptors.

Congenital Insensitivity to Pain

A rare condition where individuals cannot feel physical pain. This can lead to injuries going unnoticed and may result in serious health issues.

Dermatome

An area of skin innervated by sensory fibers from a single spinal nerve root. Used to map the distribution of sensory innervation.

Dermis

The layer of skin beneath the epidermis that contains blood vessels, nerves, and connective tissue. It plays a role in sensation and thermoregulation.

Dorsal Column Nuclei

Clusters of neurons in the brainstem that receive sensory information from the body, particularly touch and proprioception, via the dorsal column pathway.

Dorsal Column System

A sensory pathway that transmits touch and proprioceptive information from the body to the brain. It includes the dorsal columns of the spinal cord and the dorsal column nuclei in the brainstem.

Dynorphins

A type of endogenous opioid peptide that binds to opioid receptors in the brain and spinal cord. Involved in modulating pain and emotional responses.

Endogenous Opioids

Naturally occurring peptides in the body, such as endorphins, enkephalins, and dynorphins, that bind to opioid receptors and modulate pain and other physiological processes.

Endorphins

Endogenous opioid peptides produced by the brain that have pain-relieving and mood-enhancing effects. They bind to opioid receptors to reduce pain perception.

Enkephalins

Short-chain endogenous opioid peptides that bind to opioid receptors in the brain and spinal cord, playing a role in pain modulation.

Epidermis

The outermost layer of skin, providing a protective barrier against environmental damage and pathogens.

Free Nerve Ending

A type of nerve ending that lacks specialized structures and is sensitive to pain, temperature, and some touch stimuli.

Glutamate

The primary excitatory neurotransmitter in the brain. It plays a key role in synaptic transmission and plasticity, including in pain pathways.

Hypodermis

The deepest layer of skin, composed of fat and connective tissue, which insulates the body and absorbs shocks.

Labeled Lines

A concept in sensory processing where specific neural pathways are dedicated to transmitting particular types of sensory information.

Meissner’s Corpuscle

A type of mechanoreceptor located in the skin’s upper layer, responsible for detecting light touch and vibrations.

Merkel’s Disc

A type of mechanoreceptor located at an intermediate depth within the skin, involved in detecting sustained pressure and texture.

Migraines

Severe, recurrent headaches often accompanied by nausea, vomiting, and sensitivity to light and sound. They may involve complex neural and vascular mechanisms.

Naloxone

An opioid antagonist used to reverse opioid overdoses by binding to opioid receptors and blocking their effects.

Natriuretic Polypeptide B (Nppb)

A peptide involved in regulating blood pressure and fluid balance. It has also been implicated in pain modulation.

NaV1.7

A voltage-gated sodium channel expressed in sensory and sympathetic neurons.

Pacinian Corpuscle

A type of mechanoreceptor located deep in the skin and other tissues, sensitive to vibration and pressure.

Pain

An unpleasant sensory and emotional experience associated with actual or potential tissue damage.

Periaqueductal Gray

A region in the midbrain involved in the modulation of pain and defensive behavior.

Phasic Receptor

A sensory receptor that responds to changes in stimulus intensity and adapts quickly, providing information about the onset and offset of stimuli.

Piezo

A family of ion channels that respond to mechanical stimuli, playing a role in the sensation of touch and proprioception.

Placebo

A substance with no therapeutic effect used as a control in testing new drugs or as a psychological treatment.

Polymodal

Referring to receptors or neurons that respond to multiple types of stimuli, such as mechanical, thermal, and chemical.

Primary Sensory Cortex

The area of the cerebral cortex that first receives and processes sensory information from the body.

Primary Somatosensory Cortex (S1)

The region of the parietal lobe that processes tactile information from the body, organized somatotopically.

Range Fractionation

The principle that different sensory receptors are specialized to respond to different ranges of stimulus intensities, allowing for a wide range of detection.

Receptive Field

The specific area or range of stimuli to which a sensory receptor or neuron responds.

Receptor Cell

A cell that detects a specific type of stimulus, such as light, sound, or pressure, and converts it into an electrical signal.

Receptor Potential

The graded electrical potential generated in a receptor cell in response to a stimulus, which can lead to action potentials if the threshold is reached.

Ruffini’s Ending

A type of mechanoreceptor located in the skin and joints, sensitive to skin stretch and sustained pressure.

Secondary Sensory Cortex

The area of the cerebral cortex that receives input from the primary sensory cortex and is involved in higher-order processing of sensory information.

Secondary Somatosensory Cortex (S2)

A region in the parietal lobe that processes complex aspects of sensory information, including integration of tactile and proprioceptive inputs.

Sensory Pathway

The neural pathways that transmit sensory information from receptors to the brain for processing.

Sensory Receptor Organ

An organ specialized to detect specific types of sensory stimuli, such as the eye for vision or the ear for hearing.

Sensory Transduction

The process by which sensory receptors convert physical stimuli into electrical signals that can be interpreted by the nervous system.

Somatosensory

Pertaining to the sensory modalities of touch, temperature, pain, and proprioception.

Specific Nerve Energies

The doctrine that each sensory nerve carries a specific type of information to the brain, and stimulation of a nerve produces a characteristic sensation.

Stimulus

Any external or internal change that elicits a response from a sensory receptor.

Substance P

A neuropeptide involved in the transmission of pain and other sensory signals in the nervous system.

Synesthesia

A condition in which stimulation of one sensory modality leads to involuntary experiences in another, such as seeing colors when hearing sounds.

Tactile

Relating to the sense of touch.

Thalamus

A brain structure that serves as a relay station for sensory information, directing it to appropriate cortical areas for processing.

Threshold

The minimum intensity of a stimulus required to produce a detectable response in a sensory receptor.

Tonic Receptor

A sensory receptor that responds to a stimulus with a continuous, steady response as long as the stimulus is present.

Top-Down Process

Cognitive processes that influence perception based on expectations, knowledge, and prior experience, rather than solely on sensory input.

Transient Receptor Potential Type M3 (TRPM3)

An ion channel involved in the sensation of noxious heat and chemical irritants.

Transient Receptor Potential Vanilloid Type 1 (TRPV1)

An ion channel activated by heat and capsaicin, involved in the sensation of pain and temperature.

TRPM8

An ion channel activated by cold temperatures and menthol, contributing to the sensation of coolness.

Ampulla

An enlarged region of each semicircular canal that contains the receptor cells (hair cells) of the vestibular system.

Amusia

A disorder characterized by the inability to discern tunes accurately.

Anosmia

A loss of the sense of smell.

Basilar Membrane

A membrane in the cochlea that contains the principal structures involved in auditory transduction.

Bass

An aspect of pitch corresponding to the subjective experience of low-frequency sounds (especially musical sounds, such as bass guitar).

Binaural

Listening with two ears.

Central Deafness

Impaired hearing that results from damage to the auditory cortex.

Cilium

A tiny tuft of thin hairs projecting out of each olfactory receptor cell and extending through the mucous layer into the nasal cavity; thought to be the site where odorous molecules trigger electrical changes in the olfactory receptor cell.

Circumvallate Papillae

Large, dome-shaped structures located at the back of the tongue that contain taste buds.

Cochlea

A coiled, fluid-filled chamber in the inner ear containing the specialized organ for hearing, the basilar membrane.

Cochlear Implant

An electromechanical device that detects sounds and selectively stimulates nerves in different regions of the cochlea via surgically implanted electrodes.

Cochlear Nuclei

Brainstem nuclei that receive input from auditory hair cells and send output to the superior olivary complex.

Coincidence Detector

A device that senses the co-occurrence of two events.

Conduction Deafness

A hearing impairment that is associated with pathology of the external ear or middle ear cavities.

Cortical Deafness

Impaired hearing that results from damage to the auditory cortex.

Cupula

A gelatinous structure in the semicircular canals of the inner ear that moves in response to fluid motion, bending hair cells and initiating nerve impulses.

Deafness

Hearing loss so profound that speech perception is lost.

Decibel (dB)

A measure of sound intensity.

Dendritic Knob

The swollen end of a dendrite that forms a synapse with another neuron.

Diffusion Tensor Imaging (DTI)

A special use of MRI that takes advantage of the differences in how water molecules are constrained in myelin to reveal axonal tracts connecting brain regions.

Duplex Theory

A theory that we localize sound by combining information about intensity differences and latency differences between the two ears.

Ear Canal

The hollow cavity leading from the pinna to the eardrum, which in humans is about 2.5 cm long and 7 mm in diameter.

External Ear

The outermost part of the ear, including the pinna and ear canal, that collects sound waves.

Flavor

The combined sensory experience of taste and smell.

Foliate Papillae

Leaf-shaped structures located on the sides of the tongue that contain taste buds.

Fourier Analysis

A mathematical method for analyzing complex waveforms by breaking them down into simpler sine waves.

Frequency

The number of cycles per second of a sound wave, measured in hertz (Hz).

Fundamental

The lowest frequency of vibration of a standing wave.

Fungiform Papillae

Mushroom-shaped structures located on the tongue that contain taste buds.

Glomerulus

Spherical clusters of cells in the vertebrate olfactory bulb that process information from a particular class of olfactory sensory neurons and therefore a particular odor.

Gustatory System

The sensory system responsible for the sense of taste.

Hair Cell

The ears' receptors.

Harmonics

Multiples of the fundamental frequency present in a complex sound wave.

Hearing Loss

A decrease in the ability to perceive sound.

Hertz (Hz)

A unit of frequency equal to one cycle per second.

Incus

The middle ossicle in the middle ear, transmitting sound vibrations from the malleus to the stapes.