Integration of Nervous System Function

Vocabulary-style flashcards covering the integration of nervous system functions including sensory receptors, cerebral cortex areas, and memory types.

Sensation

The process initiated by stimuli acting on sensory receptors, representing how the brain receives information about the environment and body.

Perception

The conscious awareness of stimuli received by sensory receptors.

General Senses

Senses distributed over a large part of the body, categorized into somatic (e.g., touch, pressure, temperature, proprioception, pain) and visceral (e.g., pain and pressure in internal organs).

Special Senses

The distinct senses of smell, taste, sight, hearing, and balance.

Mechanoreceptors

Receptors responding to compression, bending, or stretching of cells, involved in touch, pressure, proprioception, hearing, and balance.

Chemoreceptors

Sensory receptors that respond to chemicals, specifically for smell and taste.

Thermoreceptors

Sensory receptors that respond to changes in temperature, specifically heat.

Photoreceptors

Receptors that respond to light, facilitating vision.

Nociceptors

Receptors that respond to extreme mechanical, chemical, or thermal stimuli, associated with pain and itch.

Cutaneous receptors

Exteroceptors purely associated with the skin.

Visceroreceptors

Sensory receptors specifically associated with internal organs.

Proprioceptors

Receptors associated with joints, tendons, and other connective tissue that provide information about body position and movement.

Free Nerve Endings

The simplest and most common sensory receptors; unspecialized neuronal branches that detect pain, temperature, itch, tickle, and movement.

Merkel (Tactile) Disks

Receptors located in the basal layers of the epidermis that detect light touch and superficial pressure, capable of detecting displacement of less than $1\,mm$.

Hair Follicle Receptors

Receptors that respond to the slight bending of hair; their fields overlap, making sensation sensitive but not very localized.

Pacinian (Lamellated) Corpuscles

Connective tissue-covered dendrites located deep in the dermis or hypodermis that detect deep cutaneous pressure or vibration.

Meissner (Tactile) Corpuscles

Receptors involved in two-point discrimination and determining the texture of objects, concentrated in areas like the tongue and fingertips.

Ruffini End Organ

Receptors located primarily in the dermis of the fingers that respond to continuous touch, pressure, and the stretch of adjacent skin.

Muscle Spindles

Groups of 3-10 specialized skeletal muscle cells that provide proprioception associated with muscle stretch and are involved in the stretch reflex.

Golgi Tendon Organ

Sensory receptors associated with the stretch of a tendon that respond to increased tension via the Golgi tendon reflex.

Receptor potential

A graded potential resulting from the interaction of a sensory receptor with a stimulus, also known as a generator potential.

Primary receptors

Receptors whose axons conduct action potentials directly in response to a receptor potential.

Secondary receptors

Receptors that release neurotransmitters to bind to a neuron to cause a receptor potential, used for smell, taste, hearing, and balance.

Adaptation

Decreased sensitivity to a continued stimulus, also referred to as accommodation.

Tonic receptors

Receptors that generate action potentials as long as a stimulus is applied and adapt very slowly, such as those indicating the position of a finger.

Phasic receptors

Receptors that adapt very rapidly and are most sensitive to changes in stimuli, such as those tracking a hand as it moves.

Primary somatosensory cortex

An area posterior to the central sulcus responsible for general sensory input including pain, pressure, and temperature.

Association areas

Cortical areas involved in the recognition and evaluation of stimuli (e.g., comparing current visual information to past information).

Referred Pain

A sensation in a region of the body that is not the source of the stimulus, often occurring when organ pain is felt in the skin.

Primary motor cortex

Located in the pre-central gyrus, this area is responsible for voluntary movement.

Premotor area

An area anterior to the primary motor cortex where motor functions are organized before initiation.

Prefrontal area

An area anterior to the premotor area involved in motivation, planning movements, emotional behavior, and mood.

Corpus callosum

A commissure that allows sensory information to be shared between the right and left cerebral hemispheres.

Wernicke's area

An area in the left cerebral cortex involved in sensory speech, including understanding heard language and thinking of what to say.

Broca's area

An area in the left cerebral cortex involved in motor speech, responsible for sending messages to muscles to make sounds.

Aphasia

Absent or defective speech or language comprehension caused by a lesion in the auditory/speech pathway.

Working memory

A transient but highly detailed memory associated with immediate tasks.

Procedural (Implicit) memory

A type of long-term reflexive memory involved in developing skills like riding a bicycle, controlled by the cerebellum and premotor area.

Declarative (Explicit) memory

A type of long-term memory involving the retention of facts, controlled by the hippocampus and amygdala.

Consolidation

The process of transferring short-term memory to long-term memory through the formation of new and stronger synaptic connections.

Memory engram

Also called a memory trace, this is a series of neurons and their pattern of activity involved in the long-term retention of information.