15.1 – Introduction to the Sensory Systems
Learning Objectives
- Identify the anatomy of the sensory systems and describe the main functions of the sensory systems
- Analyze, translate, and define medical terms and common abbreviations of the sensory systems
- Practice the spelling and pronunciation of sensory systems terminology
- Identify the medical specialties associated with the sensory systems and explore common diseases, disorders, diagnostic tests and procedures related to the sensory systems
Sensory Systems Word Parts
Click on prefixes, combining forms, and suffixes to reveal a list of word parts to memorize for the sensory systems.
Prefix
- bi- (two)
- bin- (two)
- a- (absence of, without, no, not, negates meaning)
- an- (absence of, without, no, not negates meaning)
- endo- (within, in)
Combining Form
- audi/o (hearing)
- aur/o (ear)
- aur/i (ear)
- blephar/o (eyelid)
- cochle/o (cochlea)
- conjunctiv/o (conjunctiva)
- cor/o (pupil)
- corne/o (cornea)
- core/o (pupil)
- cry/o (cold)
- dacry/o (tear, tear duct)
- dipl/o (two, double)
- ir/o (iris)
- irid/o (iris)
- is/o (equal)
- kerat/o (cornea)
- labyrith/o (labyrinth, inner ear)
- lacrim/o (tear, tear duct)
- mastoid/o (mastoid bone)
- myring/o (tympanic membrane, eardrum)
- ocul/o (eye)
- ophthalm/o (eye)
- opt/o (vision)
- ot/o (ear)
- phac/o (lens)
- phak/o (lens)
- phot/o (light)
- pupill/o (pupil)
- retin/o (retina)
- scler/o (sclera)
- staped/o (stapes, middle ear)
- ton/o (tension, pressure)
- tympan/o (tympanic membrane, middle ear)
- vestibul/o (vestibule)
Suffix
- -al (pertaining to)
- -algia (pain)
- -ar (pertaining to)
- -ary (pertaining to)
- -ectomy (excision or surgical removal)
- -eal (pertaining to)
- -gram (record, radiographic image)
- -graphy (process of recording)
- -ia (condition of, diseased or abnormal state)
- -ic (pertaining to)
- -itis (inflammation)
- -logist (specialist or physician who studies and treats)
- -logy (study of)
- -malacia (softening)
- -meter (instrument used to measure)
- -metry (process of measuring)
- -oma (tumour, swelling)
- -opia (vision as it relates to condition)
- -plegia (paralysis)
- -ptosis (prolapse, drooping, sagging)
- -stomy (creation of artificial opening)
- -pathy (disease)
- -pexy (surgical fixation)
- -phobia (abnormal fear, aversion to specific things)
- -plasty (surgical repair)
- -plegia (paralysis)
- -rrhea (flow, discharge)
- -sclerosis (hardening)
- -scope (instrument used to view)
- -scopy (process of viewing)
- -sis (abnormal condition)
- -tomy (incision, cut into)
Activity source: Sensory Systems Word Parts by Kimberlee Carter, from Building a Medical Terminology Foundation by Kimberlee Carter and Marie Rutherford, licensed under CC BY- 4.0. /Text version added.
Introduction to the Sensory Systems
Ask anyone what the senses are, and they are likely to list the five major senses as taste, smell, touch, hearing, and sight. However, these are not all of the senses. The most obvious omission from this list is balance. Touch can be further subdivided into pressure, vibration, stretch, and hair follicle position on the basis of the type of mechanoreceptors that perceive these touch sensations. Other overlooked senses include temperature perception by thermoreceptors and pain perception by nociceptors.
Within the realm of physiology, senses can be classified as either general or special. A general sense is one that is distributed throughout the body and has receptor cells within the structures of other organs. Mechanoreceptors in the skin, muscles, or the walls of blood vessels are examples of this type. General senses often contribute to the sense of touch, as described above, or to proprioception and kinesthesia, or to a visceral sense, which is most important to autonomic functions. A special sense is one that has a specific organ devoted to it, namely the eye, inner ear, tongue, or nose.
Gustation (Taste) and Olfaction (Smell)
Watch Taste & Smell: Crash Course Anatomy & Physiology #16 (11 min) on YouTube
Media 15.1: CrashCourse. (2015, April 27). Taste & amell: Crash Course anatomy & physiology #16 [Video]. YouTube. https://youtu.be/mFm3yA1nslE
Sensory Systems Medical Terms
Sensory Systems Medical Terms (Text Version)
Practice the following sensory system words by breaking into word parts and pronouncing.
- anisocoria (an-ī-sō-KŌR-ē-ă)
- condition of absence of equal pupil (size)
- aphakia (ă-FĀ-kē-ă)
- condition of no lens
- audiogram (OD-ē-ō-gram)
- graphic record (radiographic image) of hearing
- audiologist (od-ē-OL-ŏ-jĭst)
- specialist who studies and treats the hearing
- audiology (od-ē-OL-ŏ-jē)
- study of the hearing
- audiometer (od-ē-OM-ĕt-ĕr)
- instrument used to measure hearing
- audiometry (od-ē-OM-ĕ-trē)
- measuring hearing
- aural (OR-ăl)
- pertaining to the ear
- binocular (bĭn-ŎK-ū-lăr)
- pertaining to both eyes
- blepharitis (blĕf-ăr-Ī-tĭs)
- inflammation of the eyelid
- blepharoplasty (BLĔF-ă-rō-plăs-tē)
- surgical repair of the eyelid
- blepharoptosis (BLĔF-ă-rōp-TŌ-sĭs)
- condition of drooping of the eyelid
- cochlear (KOK-lē-ăr)
- pertaining to the cochlea
- cochlear implant (KOK-lē-ă IM-plant)
- pertaining to the cochlear implant
- conjunctivitis (kŏn-jŭnk-tĭ-VĪT-ĭs)
- inflammation of the conjunctiva
- corneal (KOR-nē-ă)
- pertaining to the cornea
- cryoretinopexy (krī-ō-RET-in-ō-pek-sē)
- surgical fixation of the retina using extreme cold
- dacrocystitis (dak-rē-ŏ-sis-TĪT-ĭs)
- inflammation of the tear (lacrimal) sac
- dacryocystorhinostomy (dak-rē-ŏ-sis-tŏ-rī-NOS-tŏ-mē)
- creation of an artificial opening between the lacrimal sac and the nose
- diplopia (dip-LŌ-pē-ă)
- condition of double vision
- electrocochleography (ē-lek-trō-kok-lē-OG-ră-fē)
- process of recording the electrical activity in the cochlea
- endophthalmitis (ĕn-dŏf-thăl-MĪ-tĭs)
- inflammation within the eye
- intraocular (in-tră-OK-yŭ-lăr)
- pertaining to within the eye
- iridectomy (ir-ĭ-DEK-tŏ-mē)
- excision of (part of) the iris
- iridoplegia (ir-ĭ-dō-PLĒ-j(ē-)ă, īr)
- paralysis of the iris
- iridotomy (ĭr-ĭ-DŎT-ō-mē)
- incision into the iris
- iritis (ī-RĪT-ĭs)
- inflammation of the iris
- isocoria (ī-sō-KŌ-rē-ă)
- condition of equal pupils
- keratitis (ker-ă-TĪT-ĭs)
- inflammation of the cornea
- keratomalacia (kĕr-ă-tō-mă-LĀ-shē-ă)
- condition of softening of the cornea
- keratometer (kĕr-ă-TŎM-ĕ-ter)
- instrument used to measure (the curvature) of the eye
- keratoplasty (KER-ăt-ō-plas-tē)
- surgical repair of the cornea
- labyrinthectomy (lab-ĭ-rin-THEK-tŏ-mē)
- excision of the inner ear (labyrinth)
- labyrinthitis (lab-ĭ-rin-THĪT-ĭs)
- inflammation of the inner ear (labyrinth)
- lacrimal (LAK-rĭ-măl)
- pertaining to the tear duct
- leukocoria (loo-kō-KŎR-ē-ă)
- condition of white pupil
- mastoidectomy (măs-tŏy-d-ĔK-tō-mē)
- excision of the mastoid bone
- mastoiditis (mas-toyd-ĪT-ĭs)
- inflammation of the mastoid bone
- mastoidotomy (măs-toyd-ŎT-ō-mē)
- incision into the mastoid bone
- myringitis (mĭr-ĭn-JĪ-tĭs)
- inflammation of the tympanic membrane
- myringoplasty (mĭr-ĬN-gō-plăst-ē)
- surgical repair of the tympanic membrane
- myringotomy (mĭr-ĭn-GŎT-ō-mē)
- incision into the tympanic membrane
- nasolacrimal (nā-zō-LAK-rĭ-măl)
- pertaining to the nose and the tear duct
- nasopharyngeal (nā-zō-FAR-in-gēl)
- pertaining to the nose and pharynx (throat)
- oculomycosis (ŏk-ū-lō-mī-KŌ-sĭs)
- abnormal condition of the eye caused by a fungus
- ophthalmalgia (ŏf-thăl-MĂL-jē-ă)
- condition of pain in the eye
- ophthalmic (of-THAL-mik)
- pertaining to the eye
- ophthalmologist (ŏf-thăl-MŎL-ō-jĭst)
- specialist of the eye
- ophthalmology (Ophth) (ŏf-thăl-MŎL-ō-jē)
- study of the eye
- ophthalmopathy (ŏf-thăl-MŎP-ă-thē)
- disease of the eye
- ophthalmoplegia (of-thal-mō-PLĒ-j(ē-)ă)
- paralysis of the eye
- ophthalmoscope (of-THAL-mŏ-skōp)
- instrument used to view the eye
- ophthalmoscopy (of-thal-MOS-kŏ-pē)
- process of viewing the eye
- optic (OP-tik)
- pertaining to vision
- optometry (op-TOM-ĕ-trē)
- measuring vision
- otalgia (ō-TĂL-jē-ă)
- condition of pain in the ear
- otologist ( ō-TŎL-ō-jĭst)
- specialist who studies and treats disorders and diseases of the ear
- otology (ō-TŎL-ō-jē)
- study of the ear
- otomastoiditis (ō-tō-mas-toyd-ĪT-ĭs)
- inflammation of the ear and mastoid bone
- otomycosis (ō-tō-mī-KŌ-sĭs)
- abnormal condition of fungus in the ear
- otopyorrhea (ō-tō-pī-ō-RĒ-ă)
- discharge of pus from the ear
- otorhinolaryngologist (ō-tō-RĪ-nō-lăr-ĭn-GŎL-ō-jĭst)
- specialist or physician who studies and treats diseases and disorders of the ears,
- otorrhea (ō-tō-RĒ-ă)
- discharge from the ear
- otosclerosis (ō-tō-sklē-RŌ-sĭs)
- condition of hardening of the ear
- otoscope(Ō-tō-skōp)
- instrument used to view the ear
- otoscopy (ō-TŎS-kō-pē)
- process of viewing the ear
- phacomalacia (făk-ō-mă-LĀ-shē-ă)
- condition of softening of the lens
- photophobia (fō-tō-FŌ-bē-ă)
- condition of sensitivity to light
- pseudophakia (SOOD-ō-FĀ-kē-a)
- condition of fake lens
- pupillary (PŪ-pĭ-lĕr-ē)
- pertaining to pupil
- pupillometer (pū-pĭl-ŎM-ĕ-tĕr)
- instrument used to measure the pupil
- pupilloscope (pū-pĭl-ŎS-kōp)
- instrument used to view the pupil
- retinal (RĔT-ĭ-năl)
- pertaining to the retina
- retinoblastoma (ret-ĭn-ō-blas-TŌ-mă)
- tumour arising from a developing retinal cell
- retinopathy (ret-ĭn-OP-ă-thē)
- disease of the retina
- retinoscopy (ret-ĭn-OS-kŏ-pē)
- process of viewing the retina
- sclerokeratitis (sklĕr-ō-kĕr-ă-TĪ-tĭs)
- inflammation of the sclera and cornea
- scleromalacia (sklĕ-rō-mā-LĀ-sē-ă)
- softening of the sclera
- sclerotomy (sklĕ-ROT-ŏ-mē)
- incision into the sclera
- stapedectomy (stā-pĕ-DEK-tŏ-mē)
- excision of the stapes
- tonometer (tō-NOM-ĕt-ĕr)
- instrument used to measure pressure (within the eye)
- tonometry (tō-NOM-ĕ-trē)
- process of measuring pressure
- tympanometer (tĭm-pă-NŎM-ĕ-tēr)
- instrument used to measure the middle ear
- tympanometry (tĭm-pă-NŎM-ĕ-trē)
- measurement of the tympanic membrane
- tympanoplasty (tĭm-păn-ō-PLĂS-tē)
- membranesurgical repair of the tympanic
- vestibular (ves-TIB-yŭ-lăr)
- pertaining to the vestibule
- vestibulocochlear (ves-tĭ-būl-ō-KŌ-klē-ar)
- vestibul/o/cochle/ar
- pertaining to the vestibule and cochlea
- xerophthalmia (zer-of-THAL-mē-ă)
- xer/ophthalm/ia
- * Rebel, does not follow the rules*
- condition of dry eye
Activity source: Sensory Systems Medical Terms by Kimberlee Carter, from Building a Medical Terminology Foundation by Kimberlee Carter and Marie Rutherford, licensed under CC BY- 4.0. /Text version added.
Gustation (Taste)
Gustation is the special sense associated with the tongue. The surface of the tongue, along with the rest of the oral cavity, is lined by a stratified squamous epithelium. Raised bumps called papillae contain the structures for gustatory transduction. There are four types of papillae based on their appearance:
- circumvallate
- foliate
- filiform
- fungiform
Within the structure of the papillae are taste buds that contain specialized gustatory receptor cells for the transduction of taste stimuli. These receptor cells are sensitive to the chemicals contained within foods that are ingested, and they release neurotransmitters based on the amount of the chemical in the food. Neurotransmitters from the gustatory cells can activate sensory neurons in the facial, glossopharyngeal, and vagus cranial nerves.
Only a few recognized submodalities exist within the sense of taste, or gustation. Until recently, only four tastes were recognized: sweet, salty, sour, and bitter. Research at the turn of the 20th century led to the recognition of the fifth taste, umami, during the mid-1980s. Recent research has suggested that there may also be a sixth taste for fats or lipids.
Olfaction (Smell)
Like taste, olfaction is also responsive to chemical stimuli. The olfactory receptor neurons are located in a small region within the superior nasal cavity. The nasal epithelium, including the olfactory cells, can be harmed by airborne toxic chemicals. Scent receptor messages travel to the cerebrum, specifically to the primary olfactory cortex that is located in the inferior and medial areas of the temporal lobe and additionally to the hypothalamus, where smells become associated with long-term memory and emotional response.
Did You Know?
The human body can detect over 10,000 odours.
Concept Check
- Which parts of the brain are active with recording and associating scents with memories and emotions?
- Recall and list the four types of papillae (taste buds) found on the tongue.
Attribution
Except where otherwise noted, this chapter is adapted from “Sensory Systems” in Building a Medical Terminology Foundation by Kimberlee Carter and Marie Rutherford, licensed under CC BY 4.0. / A derivative of Betts et al., which can be accessed for free from Anatomy and Physiology (OpenStax). Adaptations: dividing Sensory Systems chapter content into sub-chapters.
A sensory neuron that responds to mechanical pressure
specialized neurons that respond to changes in temperature
Sensory neurons that respond to pain
body movement
body movement
pertaining to internal organs
Chemical messengers which transmit signals across a chemical synapse from one neuron to another neuron/nerve cell.
pertaining to tongue and throat
Umami is a Japanese word that means delicious taste, and is often translated to mean savory
sense of smell