Chapter 4: Sensation and Perception Flashcards
When a stimulus is at its absolute threshold what percentage of the time will it be detected?
50%
Which type of cells are found on the fovea?
Cones
Which theory of colour vision provides the best explanation of complimentary colour afterimages?
Opponent process theory
Rachel is looking at her dog. The dog itself is the ____ stimulus, the image of the dog on her retina is the ____ stimulus.
Distal; proximal
Which of the following is an example of pictoral depth cue?
Interposition
Research suggests that when an object evokes feelings of ____ it appears further away than it is.
Disgust
Which physical property of sound determines its pitch?
Wavelength
Which of the following theories suggests that sounds of different pitch cause the hair cells to vibrate at different rates?
Frequency theory
Where in the human body can you find the ossicles?
In the middle of the ear
Hilary sees a steady image of the world outside the car window despite the fact that she is travelling over a bumpy dirt road. Which perceptual system is detecting the bumps in the road?
Vestibular system
Focuses light rays falling on the retina
Lens
Regulates the amount of light passing to the rear of the eye
Pupil
The neural tissue lining the inside back surface of the eye
Retina
A hole in the retina that corresponds to the blind spot
Optic disk
A tiny spot in the centre of the retina where visual activity is greatest
Fovea
Consists of rods and cones, which are organized into receptive fields
Visual receptors
Play a key role in night and peripheral vision and greatly outnumber cones
Rods
Play a key role in day and colour vision and provide greater activity than rods
Cones
A collection of rods and cones that funnel signals to specific visual cells in the retina or the brain
Receptive fields
Projects through the thalamus, where signals are processed and distributed to the occipital lobe.
Main visual pathway
mediates the ability to localize visual objects in space
Second visual pathway
In the occipital lobe handles initial processing of visual input
Primary visual cortex
Neurons that respond selectively to specific features of complex stimuli
Feature detectors
Works by removing some wavelengths of light, leaving less light
Subtractive colour mixing
Works by putting more light in mixture than any one light
Additive colour mixing
Holds that the eye has three groups of receptors sensitve to wavelengths associated with red, green, blue
Trichromatic theory
Holds that receptors make antagonistic responses to three pairs of colours
Opponent process theory
What is form perception?
- The same visual input can result in very different perceptions
- Form reception is selective, as the phenomenon of inattentional blindness demonstrates
- Some aspects of form perception depend on feature analysis, which involves detecting specific elements and assembling them into complex forms
- Gestalt principles help explain how scences are organized into discrete forms
- Form perception often involves perceptual hypothesis, which are inferences about the forms that could be responsible for the stimuli sensed
Clues about distance based on the differing views of the two eyes
Binocular cues
Refers to the fact that the right and left eyes see slightly different views of objects. The closer the object gets, the greater the disparity
Retinal disparity
Clues about distance based on the image in either eye alone
Monocular cues
Are monocular clues that can be given in a flat picture, such as linear perspective, texture gradients, relative size, height in plane, interposition, and light and shadow.
pictoral cues
A discrepency between the appearance of a visual stimulus and its physical reality
visual illusion
such as the Muller-Lyer illusion, the Ponzo illusion, and the moon illusion - show that perceptual hypotheses can be wrong and that perception is not a simple reflection of objective reality
Illusions
The external ear’s sound-collecting cone
Pinna
A taut membrane (at the end of the auditory canal) that vibrates in response to sound waves
Eardrum
Three tiny bones in the middle ear that convert the ear drum’s vibrations
Ossicles
The fluid-filled, coiled tunnel that houses the inner ear’s neural tissue
Cochlea
Holds hair cells that serve as auditory receptors
Basiliar membrane
Perception of pitch depends on the portion of the basilar membrane vibrated
Place theory
Perception of pitch depends on the basilar membrane’s rate of vibration
Frequency theory
Consists of locating where a sound is coming from in space
Auditory localization
Incoming pain signals can be blocked in the spinal cord
Gate-control theory
____ absorb chemicals in saliva and trigger impulses rooted through the thalamus.
Taste cells
Olfactory ____ absorb chemicals in the nose and trigger neural impulses
cilia
Smell is the only sensory sysyem that isn’t routed through the ____.
Thalamus
____ receptors in the skin respond to pressure, temperature, and pain
Sensory
Pain signals travel along _____ _____ that registers localized pain and a ____ ____ that carries less localized pain sensations.
Fast pathway
Slow pathway
Light waves vary in ____ (height) and in ____ (the distance between peaks)
Amplitude and wavelength
