Test 1 Flashcards
Name the sensory systems of the body and describe what they do.
5 main ones:
- Visual
- Auditory
- Olfactory
- Gustatory
- Tactile
Additional ones:
- Vestibular (balance and position in terms of gravity)
- Proprioception (position of the body)
- Interoception (sensations of the state of internal organs, such as hunger, thirst, nausea)
Why is there more of the cortex devoted to vision than to any other modality?
It is because visual perception is the most important when it comes to survival (e.g. noticing a predator or identifying any other dangerous circumstances).
What kind of receptors are in the retina?
There are 2 types: rod and cone cells.
Rod cells: specialized in detection of movement. Responsible for vision in low light environments.
Cone cells: specialized in color vision and sharpness of vision in well-lit conditions. There are three types of cone cells, each sensitive to a specific range of wavelengths in the visible spectrum.
Why do people have 2 eyes? What is “binocular disparity”?
It is thought that people have 2 eyes and not just one because this allows for an object to be seen from a slightly different angle by each eye. The result is that a 3-dimensional image is constructed in the brain by combining the input coming from both eyes.
What is the function of the pupil?
The pupil is an opening in the iris and determines how much light enters the eye. It becomes smaller when the light is very bright, and bigger when the light is faint.
What is sensory adaptation?
Sensory adaptation is a phenomenon in which our sensory receptors become less responsive to constant or repetitive stimuli and our senses start to “ignore” it.
Example: hum of the refrigerator, smell of a Christmas tree in a room - after a while, these constant stimuli are no longer noticeable, because we got used to them.
How are rod and cone cells different?
Rod cells: specialized in detection of movement. Responsible for vision in low light environments.
Cone cells: specialized in color vision and sharpness of vision in well-lit conditions. There are three types of cone cells, each sensitive to a specific range of wavelengths in the visible spectrum.
What is two-point discrimination?
Two-point discrimination is the ability to feel and distinguish two separate points when they are touched on your skin simultaneously.
Highly sensitive areas, like your fingertips, can detect smaller separations between the points, while less sensitive areas, like your forearm, need a larger separation to distinguish them as separate points.
What are the 5 flavors that the tongue can detect?
- Sweet
- Salty
- Sour
- Bitter
- Umami
What is double disassociation?
A double dissociation is a situation where two related functions or abilities are disrupted in different individuals, and each person has a different combination of impaired and intact functions.
What is size constancy?
It’s our ability to perceive an object as having a consistent size, regardless of its distance from us.
Example - a car: when it’s far away, it appears small, but as it approaches, it appears larger. However, your brain adjusts for this change in perceived size due to the car’s changing distance.
Why has color vision developed?
Color vision has developed as it was necessary for survival and reproduction in the stone age environments.
These are the primary benefits:
- Improved detection of ripe fruits.
- Detection of predators and prey in the environment.
What is the Young-Helmholtz theory?
The Young-Helmholtz or trichromatic theory suggests that there are three types of color receptors in our eyes, each sensitive to a different range of colors: red, green, and blue.
Red-green color blindness is the most common deficiency. That’s because these type of cone cells are more likely to be damaged or missing.
Theories for color vision (trichromatic theory and
opponent process theory)
The Young-Helmholtz or trichromatic theory suggests that there are three types of color receptors in our eyes, each sensitive to a different range of colors: red, green, and blue.
The opponent process theory proposes that there are three pairs of opposing color receptors or channels in our visual system, and these pairs work together to create the sensation of color. The three pairs are:
- Red-Green
- Blue-Yellow
- Black-White
Describe the stimulus processing pathways
that lead to the production of visual sensations and
hearing
Visual Sensations (Seeing):
- When you look at something, light from the object enters your eyes.
- The light goes through the lens and hits the back of your eye, which has special cells called photoreceptors.
- These photoreceptors turn the light into electrical signals (transduction).
- These electrical signals travel to the brain through the optic nerve.
- In the brain, different parts process these signals, allowing you to see and understand what you’re looking at.
Hearing (Auditory Perception):
- When you hear a sound, like someone talking, sound waves travel through the air.
- These sound waves go into your ears and make your eardrums vibrate.
- These vibrations are converted into electrical signals by tiny hair cells in your inner ear (transduction).
- The electrical signals travel to the brain through the auditory nerve.
- In the brain, various areas process these signals, helping you understand and make sense of the sounds you hear.
