Sensation and Perception (CH2) Flashcards
What is behind the iris and helps control the refraction of the incoming light?
Lens of the eye
Contraction of the ciliary muscle (part of the ciliary body) is under what type of control?
Parasympathetic
Behind the lens of the eye, there is a transparent gel that supports the retina. This is called?
Vitreous Humor
When the ciliary muscle of the eye contracts, it pulls on suspensory ligaments and changes the shape of the lens. What is this phenomenon known as?
Accommodation
The back of the eye that behaves like a screen that consists of neural elements and blood vessels. It’s function is to convert incoming photons of light to electrical signals.
Retina
Used for color vision and to sense fine details in the retina.
Cones
More functional in reduced illumination (night vision), and only allow sensation of light and dark because they contain a single pigment called rhodpsin (not involved with color).
Rods
Rods and cones connect with these cells, which highlight gradients between adjacent rods or cones. These cells then synapse on ganglion cells, which group together to form the optic nerve.
Bipolar Cells
As the number of receptors that converge through the bipolar neurons onto one ganglion cell increases, the resolution _________?
Decreases
T/F: Color vision has a greater sensistivity to fine detail than black and white vision does.
True, because there more rods than cones
These cells receive input from multiple retinal cells in the same area before the information is passed on to ganglion cells. They accentuate slight differences b/w the visual information in each bipolar cell.
Amacrine and Horizontal Cells
The ability to simultaneously analyze and combine information regarding color, shape and motion (cohesive image of the world).
Parallel Processing
Our visual pathways contain cells specialized in detection of color, shape or motion.
Feature Detection
These cells permits us to see very fine details when thoroughly examining an object (high color spacial resolution makes this possible).
Parvocellular Cells
Parvocellular cells can only work with stationary or slow moving objects because they have a very low _____ _________.
Temporal Resolution
These cells are used to detect motion (they have a high temporal resolution). These cells also have have low color spatial resolution, so the image may appear blurry.
Magnocellular Cells
What is the only sense that does not pass through the thalamus (travels unfiltered-into higher order brain centers).
Smell
What are the four modalities of somatosensation?
- Pressure - Vibration - Pain - Temperature
Deep pressure and vibration
Pacinian Corpuscles
Light touch
Meissner Corpuscles
Deep pressure and texture
Merkel Cells (Discs)
Stretch
Ruffini Endings
Pain and Temperature
Free Nerve Endings
With Brown-Sequard Syndrome, half of the spinal cord is severed. On the severed side, the patient loses sense of pressure and vibration. What happens on the opposite side?
The patient will lose sense of pain and temperature.