Module 21: The Other Senses Flashcards
Gate-Control Theory
The theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain. The “gate” is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers (such as massage) or by information coming from the brain (distracting thoughts)
*interneuron fires from the touch signal from the mechanoreceptor (large fiber/touch) reaching it first - faster track - then the interneuron is in its resting period once the nociceptor arrives
Nociceptors
Sensory receptors that detect hurtful temperatures, pressure, or chemicals
What are the four basic senses of touch?
Pressure, warmth, cold, and pain
Phantom Limb Sensation
Misinterpreting the spontaneous central nervous system activity that occurs in the absence of normal sensory input.
Without normal sensory input, the brain may misinterpret and amplify spontaneous but irrelevant central nervous system activity.
Tinnitus
A ringing or buzzing in the ears - phantom sounds
How does the somatosensory cortex help us sense touch?
The somatosensory cortex receives sensory information from our skin as well as other senses
How is pain understood?
Our experience of pain reflects both bottom-up sensations and top-down cognition. Pain is a biopsychosocial event. As such, pain experiences vary from group to group and from person to person.
What are the biological influences of pain?
- activity in spinal cords large and small fibers
- genetic differences in endorphin production
- the brain’s interpretations of the central nervous system activity
What are the psychological influences of pain?
- attention to pain
- learning based on experience
- expectations
What are the Social-Cultural Influences?
- Presence of others
- empathy for other’s pain
- cultural expectations
How is pain biological?
Sensory receptors called nociceptors mostly in your skin, but also in your muscles and organs - detect hurtful temperatures, pressures, or chemicals.
What is a pain circuit?
Sensory receptors, nociceptors, respond to potentially damaging stimuli by sending an impulse to the spinal cord, which passes the message to the brain, which interprets the signal as pain.
How is pain psychological?
Pain is impacted by how much attention we give to it. If we distract our minds with other thoughts the pain feels as if it has diminished.
Our memories of pain may be edited from the actual pain we felt (remember pain’s peak and the end)
How is pain social-cultural?
We tend to perceive more pain when others seem to be experiencing pain.
We get cues on how to perceive pain from our culture’s views on pain.
What are some methods for controlling pain?
Pain control therapies may include drugs, surgery, acupuncture, electrical stimulation, massage, exercise, hypnosis, relaxation training, meditation, and thought distraction.
Gustation
Taste
On the top and sides of your tongue are 200 or more taste buds, each containing a pore that catches food chemicals.
Olfaction
Smell
We smell something when molecules of a substance carried in the air reach a tiny cluster of receptor cells at the top of each nasal cavity
What are the five basic tastes we can detect and their survival functions?
Sweet: energy source
Salty: Sodium essential to physiological processes
Sour: Potentially toxic acid
Bitter: Potentially poisons
Umami: Proteins to grow and repair tissue
How do we actually taste food?
Each taste bud pore, 50 to 100 taste receptor cells project antenna-like hairs that sense food molecules. This is where the chemicals in food are transduced to neural messages for the brain.
- some receptors respond mostly to one of the 5 taste
- each receptor transmits its message to a matching partner cell in your brain’s temporal lobes
How does our sense of smell operate?
These 20 million olfactory receptors respond selectively - to the aroma of something - this is where odors are transduced to neural messages for the brain.
- instantly they alert the brain through their axon fibers
Where does transduction of olfaction (smell) occur?
Olfactory receptors - nasal cavity
Where does transduction of gustation (taste) occur?
papillae - gustation receptor cells
What is the process of olfaction?
- Odorants bind to receptors
- Olfactory receptor cells are activated and send electric signals
- The signals are relayed via converged axons
- The signals are transmitted to higher regions of the brain
Sniffing enhances aroma on it’s way to the receptors and receptor cells send messages to the brain’s olfactory bulb – to the temporal lobe’s primary smell cortex and to the parts of the limbic system involved in memory and emotion.
Remember
The sense of smell (Olfaction) is the only one of the five senses that does not pass neural information through the thalamus
How are taste, smell, and memory related?
Information from the taste buds travels to an area between the frontal and temporal lobes of the brain. This information registers near where the brain receives input from our sense of smell which interacts with taste.
- the brain’s circuitry for smell also connects with areas involved in memory storage, which helps explain why a smell can trigger a memory.
Kinesthetic Sense
Position and motion detectors in muscles, tendons, and joints sense the position and movement of body parts.
Vestibular Sense
Fluid-filled semicircular canals and a pair of calcium crystal-filled vestibular sacs located in the ears monitors the head’s (and body’s) movements
- sense body movement & position
- sense of balance
How do our senses interact?
Our senses can influence each other
- smell impacts taste
- clogged nose less taste
- visual image better w/ noise
- soft sound w/ visual cue
Embodied Cognition
The influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.
ex. holding warm drink rather than a cold one people were more likely to rate someone more warmly, fell closer to them, and behave more generously
Synesthesia
Few select individuals
The brain circuits for two or more senses become joined in a phenomenon called synesthesia where the stimulation of one sense (such as hearing sound) triggers an experience of another (such as seeing color)
Nociceptors
A sensory receptor for painful stimuli
McGurk Effect
Seeing a speaker saying one syllable while hearing another
Semicircular canals
Contain fluid that moves when your head rotates or tilts
Vestibular Sacs
Connects the semicircular canals with the cochlea
Describe the process through which you are able to taste the food you most recently ate
Our tongues contain a bunch of tiny bumps called PAPILLAE. Your TASTE BUDS are tiny parts of your Papilla. Getting even smaller the taste buds contain dozens of chemoreceptors that detect the chemicals in food. These are also referred to as TASTE CELLS. The molecules from our food break down or dissolve in our salvia and the molecules diffuse into the taste cells. Afterwards, the taste cells create an electrical impulse, an action potential, that will send information to our brains through the cranial nerves to then be interpreted.
Sensory Interaction
The principle that one sense may influence another, as when the smell of food influences its taste
Olfactory Receptor
Protein capable of binding odor molecules - each has a single external process that extends to the surface of the epithelium and gives rise to a number of cilia.
Olfactory Bulb
A brain structure responsible for our sense of smell. Located at the tip of the olfactory lobe, the bulb processes information about odors after receiving sensory input from the nose.
Olfactory nerve
The cranial nerve that relays sensory information about the smell to the brain
