Midterm 1 Flashcards
What is the perceptual process?
The steps we take (seven) plus “knowledge” inside our head to summarize the major events that occur in the environment
What are the first two steps of the perceptual process?
Stimuli i.e. Environmental stimulus - the tree that the person is observing
What is the principle of transformation?
Stimuli and responses created by stimuli are transformed or changed, between the environmental stimulus and perception
When a reflected light reaches the eye, it is transformed as it is focused by the eye’s optical system, which is the __ at the front of the eye and the __ directly behind it. If these optics are working properly, they form a sharp image of the tree on the __ of the person’s __, a 0.4-mm thick network of nerve cells that covers the back of the eye
Cornea; lens; receptors; retina
What is the principle of representation?
Everything a person perceives is based not on direct contact with stimuli but on representations of stimuli that are formed on the receptors and on activity in the person’s nervous system
__ are cells specialized to respond to environmental energy, with each sensory system’s receptors specialized to respond to a specific type of energy
Sensory receptors
__ receptors respond to light, __ receptors to pressure changes in the air, __ receptors to pressure transmitted through the skin, and __ & __ receptors to chemicals entering the nose and mouth
Light; auditory; touch, smell taste
When the visual receptors that line the back of the eye receive the light reflected from the tree, what two things do they do?
- Transform environmental energy into electrical energy
2. They shape perception by the way they respond to stimuli
The transformation of one form of energy (i.e. light energy) to another form (i.e. electrical energy) is called __
Transduction
Electrical signals from each sense arrive t the __ for that sense in the cerebral cortex of the brain
Primary receiving area
The __ is a 2-mm thick layer that contains the machinery for creating perceptions, language, memory, and thinking
Cerebral cortex
The primary receiving area for vision occupies most of the __ lobe; the area for hearing is located in part of the __ lobe; and the area for the skin senses - touch temperature and pain is located in an area in the __ lobe
Occipital; temporal; parietal
The __ lobe receives signals from all of the senses, and it plays an important role in perceptions that involve the coordination of information received through two or more senses
Frontal
__ involves the interactions between the signals traveling in networks of neurons early in the system, in the retina; later, on the pathway to the brain; and finally within the brain
Neural processing
__ which is conscious awareness of the object (i.e. tree), and __, which is placing an object in a category, such as a “tree” that gives it meaning
Perception; recognition
What is visual form agnosia?
An inability to recognize objects i.e. may be able to perceive the object and recognize parts of it - but cannot recognize it as a whole
The final behavioral response is __, which involves motor activities
Action i.e. walk toward the tree or climb it
__ processing is processing that is based on the stimuli reaching the receptors; __ processing refers to processing that is based on knowledge
Bottom-up; top-down
The __ approach measures the relationship between the stimuli and the behavioral response
Psychophysical
Horizontal and vertical lines (stimuli) resulted in better detail vision (the behavioral response) than slanted lines, this detail vision is called the __
Oblique effect
The __ approach involves measuring two relationships, the relationship between stimuli (steps 1-2) and physiological responses (steps 3-4)
Physiological approach
__ is the minimum stimulus intensity that can just be detected
Absolute threshold
What is the method of limits (Fechner’s classical psychophysical methods)?
The experimenter presents stimuli in either ascending order (intensity increased) or descending order (intensity decreased) which indicates the results of an experiment that measure’s a person’s threshold for hearing a tone
What is the method of adjustment?
The stimulus intensity is either increased or decreased until the stimulus can just be detected. However, the observer adjusts the stimulus intensity continuously until he/she can barely detect the stimulus
What is the method of constant stimuli?
The experimenter presents 5 to 9 stimuli with different intensities in random order. On each trial, observer says yes or no to indicate whether he/she sees the light
Which method of the method of limits is the most accurate?
the method of constant stimuli, because it involves many observations and stimuli are presented in random order
Disadvantage - Time-consuming
What is the difference threshold?
The smallest amount by which two sensory stimuli can differ in order for someone to perceive them as different
What is the magnitude estimation experiment?
Requires subjects to estimate the magnitude of physical stimuli by assigning numerical values proportional to the stimulus magnitude they PERCEIVE
- perceived magnitude
When the increased perceived magnitude is SMALLER than the increase in stimulus intensity, it is called __
Response compression
As intensity is increased, perceptual magnitude increases more than intensity. This is called __
Response expansion
One way to measure behavioral response to a stimulus is the __, in which a person is asked to describe what he or she is perceiving or to indicate when a particular perception occurs
Phenomenological method
What is visual search?
Finding one stimulus among many, as quickly as possible i.e. searching for a friend’s face in a crowd
__ is the time between presentation of the stimulus and the observer’s response to the stimulus
Reaction time
The energy in the electromagnetic spectrum can be described by its __ - the distance between the peaks of the electromagnetic vages
Wavelength
Visible light, the energy within the electromagnetic spectrum that humans can perceive, has wavelengths ranging from about __ nanometers
400-700
Light can be described as consisting of small packets of energy called __
Photons (one photon - smallest possible packet)
Light reflected from the objects in the environment enters the eye through the __ and is focused by the __ and __ to form sharp images of the objects on the __, the network of neurons that covers the back of the eye and that contains the receptors for vision
Pupil; cornea; lens; retina
What are rods and cones?
Visual receptors that contain light-sensitive chemicals called visual pigments that react to light and trigger electrical signals
__ is the change in the lens’s shape that occurs when the ciliary muscles at the front of the eye tighten and increase the curvature of the lens so that it gets thicker
Accommodation
The distance at which your lens can no longer accommodate to bring close objects into focus is called the __
Near point
What is presbyopia?
The distance of the near point increases as a person gets older
- most 20 year olds is about 10cm
What is myopia, or nearsightedness?
Inability to see distant objects clearly
What is refractive myopia?
The cornea and/or lens bends the light too much
What is axial myopia?
The eyeball is too long
The distance at which light becomes focused on the retina is called the __
Far point; when the object is at the far point, a person with myopia can see it clearly
What is hyperopia, or farsightedness?
The ability to see distant objects clearly but has trouble seeing nearby objects
In the __ eye, the focus point for parallel rays of light is located behind the retina, usually because the eyeball is too short
Hyperopic
What is transduction?
The transformation of one form of energy into another form of energy
vision - light energy into electrical energy
Visual pigments have two parts:
1) A long protein called opsin
2) Smaller light-sensitive component called retinal