Sensory systems : Vision, touch, hearing, taste and movement Flashcards
(51 cards)
What is the hierarchical organization of sensory systems?
The hierarchical organization includes:
* Association cortex
* Secondary sensory cortex
* Primary sensory cortex
* Thalamic Nuclei
* Receptors
each level takes input from the lower levels and adds its own layer to analysis
Each level takes input from lower levels and adds its own analysis layer.
What is the difference between sensation and perception?
Sensation is the detection of the presence of a stimuli, while perception is the higher-order process of interpreting sensations and integrating them.
What role does the iris play in vision?
The iris regulates the size of the pupil, controlling the amount of light that enters the eye.
What is the function of the fovea?
The fovea is the area in the center of the retina that is specialized for high-acuity vision.
What types of receptors are found in the retina?
The receptors in the retina are:
* Rods
* Cones
How do rods and cones differ in their response to light?
Rods respond best to faint light and have high convergence, while cones respond best to bright light and are essential for color vision with low convergence.
What is the primary visual pathway from the retina to the brain?
The primary visual pathway is the retina-geniculate-striate pathway, where signals go through the thalamus (LGN) and then to the primary visual cortex.
What is edge perception?
Edge perception is also known as contrast perception.
What are saccades in the context of eye movement?
Saccades are small, rapid movements of the eyes that are critical for high-acuity vision.
What is component processing in color vision?
Component processing involves three different types of cones that respond to short, medium, and long wavelengths.
What is opponent processing in color vision?
Opponent processing refers to neurons responding in opposite directions to complementary colors at all levels of the visual pathway except for the receptors.
What causes color blindness?
Color blindness results from a deficiency or absence of photopigments sensitive to certain wavelengths, commonly red or green deficiencies.
How does size constancy work in perception?
Size constancy allows us to perceive objects as the same size despite changes in distance or context.
What are the main streams in the visual system?
The main streams are:
* Dorsal stream (where)
* Ventral stream (what)
What happens if the dorsal stream is damaged?
If the dorsal stream is damaged, a person can describe an object but may have difficulty grasping it.
What happens if the ventral stream is damaged?
If the ventral stream is damaged, a person may have difficulty describing and imagining an object but can still reach for it.
What is the binding problem in vision?
The binding problem refers to the challenge of how sensory information converges to represent complex stimulus characteristics without a single neuron for each object.
What pathways are involved in touch and pain sensation?
The pathways are:
* Pathway I (dorsal-column medial lemniscus system) - touch and proprioception
* Pathway II (anterolateral system) - pain and temperature
What neurotransmitters are released for mild and strong pain?
For mild pain, glutamate is released; for strong pain, glutamate and substance P are released.
What is the role of endorphins in pain relief?
Endorphins inhibit the release of substance P in the spinal cord, alleviating pain.
What is the impact of extensive damage to the right posterior parietal lobe?
Extensive damage can result in asomatognosia, which is the failure to recognize parts of one’s own body.
What do senses respond to?
Biologically relevant stimuli
Senses are specialized and evolved to provide useful information
What do senses respond to?
Biologically relevant stimuli. Senses are specialized and evolved to provide useful information
Where are taste buds grouped on the tongue?
In papillae, The number of fungiform papillae influences sensitivity to all tastes
