Vision Flashcards
What type of energy does light represent?
Electromagnetic energy
What triggers the generation of neural impulses in the retina?
Photoreceptors acting on light
What are the two main pathways from the retina to the brain?
Midbrain and cerebral cortex
What is the role of the pupil in the eye?
Regulates the amount of light entering the eye
How do rods and cones differ in light sensitivity?
Rods are about 1000 times more sensitive to light than cones
What do cones primarily contribute to in vision?
Color vision
What is phototransduction?
The conversion of light into electrical signals in rods and cones
What is the optic chiasm?
The structure where optic nerve fibers from each eye meet and cross
What is binocularity?
The ability of visual areas to respond to input from both eyes
What does the receptive field refer to?
The region of retina over which a visual cell responds
What is the significance of orientation selectivity in visual neurons?
Neurons respond best to lines or edges of a specific orientation
What phenomenon occurs when individuals with damage to primary visual cortex cannot consciously see but can accurately reach for objects?
Blindsight
What is the role of the cerebral cortex in visual processing?
It forms and acts upon sensory information for decision making
Fill in the blank: The process of making a visual decision about stimuli is often a _______ choice.
simple
What is the MT area in the brain associated with?
Processing visual motion information
What happens to the activity of neurons in V5 when the proportion of dots moving in their preferred direction increases?
Their activity increases systematically
What does the Necker cube illustrate about perception?
It demonstrates perceptual reversibility despite a static retinal image
What are the two types of ganglion cells mentioned?
- Small cells
- Large M-type (magnocellular) cells
True or False: The visual cortex is completely static and does not change with experience.
False
What is the primary function of the visual cortex’s columnar organization?
To interpret different aspects of the visual world
What is the term for the innate ability of the visual system to adapt based on experience?
Plasticity
Fill in the blank: The human eye contains approximately _______ million photoreceptors.
125
What is the purpose of using behavioral tasks in experimental neuroscience?
To understand the neural basis of decision-making
What is a common task used in neuroscience to analyze decision-making in visual stimuli?
Making a choice between two stimuli
What is the Necker cube known for?
It is constantly reversing perceptually.
How do certain neurons respond to different wavelengths of light?
Some respond best to long wavelengths, others to short wavelengths.
What does the cell firing pattern in V1 indicate about color perception?
It does not ‘perceive’ color but responds to identical wavelength mixtures.
Which area of the brain is suggested to enable color perception?
Area V4.
What is the role of area V5 in visual processing?
It registers perceived motion, not just the motion of visual stimuli.
What phenomenon occurs when observers experience a shift between vertical and horizontal lines?
Binocular rivalry.
Fill in the blank: The visual world is appreciated through the entry of _______ into the eyes.
[light]
What do neurons in many different areas of the visual cortex reflect during perceptual switches?
The observer’s perception switching from one interpretation to another.
What is the significance of Colin Blakemore’s contributions to understanding the visual system?
He conducted pioneering studies on how the visual system develops.
What does the ‘handshake’ of axons in the developing cortex indicate?
It represents interactions between different parts of a pathway in the embryonic brain.
True or False: Neurons that prefer rightwards movement fire equally regardless of perceived direction.
False.
What type of figure is used to explore neural signals involved in visual decision-making?
Reversible figures.
What visual phenomenon causes observers to perceive the same set of dots moving in different directions?
Illusion of movement.
