Khan 300 Page Psyc/Soc Flashcards
Binocular cues
Gives sense of depth and gives retinal disparity
Convergence
Gives humans idea of depth based on how much eyeballs are turned. Things far away- eye muscles relaxed. Things close- eye muscles contract
Monocular cues
- Form of an object: relative size, interposition/overlap (object that is in front is closer), relative height, shading and contour
- Motion: motion parallax: relative motion (things farther away move slower)
- Constancy: perception of object doesn’t change even if the image cast on the retina is different (size constancy; shape constancy)
Sensory adaptation
Our senses are adaptable and they can change their sensitivity to stimuli
Weber’s law
DeltaI/Initial intensity = k (constant)
Absolute threshold of sensation
The minimum intensity of stimulus needed to detect a particular stimulus 50% of the time
Subliminal stimuli
Stimuli below the absolute threshold of sensation
Types of somatosensation
Temperature (thermoception), pressure (mechanoception), pain (nociception), and position (proprioception)
How neurons encode for timing
*Non-adapting: neuron consistency fires at a constant rate
*Slow-adapting: neuron fires in beginning of stimulus and calms down after a while
*Fast-adapting: neuron fires as soon as stimulus start…then stops firing. Starts
again when stim stops
Inner ear
- Has semicircular canals that are filled with endolymph
- When we rotate head, the fluid shifts in the semicircular canals
- Endolymph doesn’t stop spinning same we do (contributes to dizziness and vertigo)
Otolithic organs
Help us to detect linear acceleration and head positioning. In these are CaCO3 (Calcium carbonate) crystals attached to hair cells in
viscous gel. If we go from lying down to standing up, they move, and pull on hair cells, which triggers AP
Signal Detection Theory
*Hit, the subject responded affirmative when a signal was present,
*False Alarm, the subject perceived a signal when there was none
present;
*Correct Rejection, a correct negative answer for no signal
*Miss, a negative response to a present signal
Bottom up Processing
Begins with stimulus. Stimulus influences what we perceive (our perception)
Top-down Processing
Uses background knowledge influences perception
Gestalt Principle: Similarity
Items similar to one another grouped together by brain
Gestalt Principle: Pragnanz
Reality organized reduced to simplest form possible. Ex. Olympic rings, where the brain automatically organizes these into 5 circles, instead of more complex shapes.
Gestalt Principle: Proximity
Objects that are close are grouped together
Law of Common Fate
For example, if there are an array of dots and half the dots are moving upward while the other half are moving downward, we would perceive the upward moving dots and the downward moving dots as two distinct units
Law of Past Experience
The law of past experience implies that under some circumstances visual stimuli are categorized according to past experience
Contextual Effects
The context in which stimuli are presented and the processes of perceptual organization contribute to how people perceive those stimuli (and also that the context can establish the way in which stimuli are organized)
Cornea
First part of eye light hits; starts to bend light
Anterior chamber of eye
Filled with aqueous humour, which provides pressure to maintain shape of eyeball
Pupil
Opening in the middle of this iris. Size can get bigger or smaller
Iris
Gives eye color. Muscle that constricts/relaxes to change size of pupil
Lens
Bends light so it goes to back of eyeball. Focuses light specifically on the fovea of the retina. Adjust how much it bends the light by changing its shape, using the
suspensory ligaments.
Retina
Inside, back area
filled with photoreceptors,
where the ray of light is converted from a physical waveform to an electrochemical impulse
that the brain can interpret
Fovea
Completely covered in cones, no rods (rest of retina is covered in primarily rods)
Cones
Detect color and discern high level of detail in what you are observing
Transmission
electrical activation of one neuron by another
neuron
Perception
Conscious sensory experience of neural
processing
Phototransduction cascade
What happens when light hits rod/cone:
1. Light hits rods (which causes rod to turn off); bipolar cell turns on; retinal ganglion cell turns on; optic nerve; brain
Opponent Process Theory of Color Vision
Have cones that perceive 4 colors: red, green, blue, and yellow. Red and green oppose each other, as do blue and yellow cones
Rods versus cones
- More rods than cones
- Cones in fovea
- Rods more sensitive (more important to see light than detail/color)
- Cones detect color but also some light
- Rods have slow recovery and cones have fast recovery (eyes adjust to darkness)
Parvocellular pathway
Good at spatial resolution (boundaries, shape, color) but poor at motion (temporal)
Magnocellular pathway
Good at temporal (time and motion)
Place Theory
Place theory posits that one is able to hear different pitches because different sound waves trigger activity at different places along the cochlea’s basilar membrane.
Base vs apex of cochlea
Base (start of cochlea) activated by high freq sounds
Apex (end of cochlea) activated by low frequency
(THINK: long wavelengths can travel farther)
