Quiz 1 - Chapters 1-3 Flashcards
(25 cards)
“Perceiving machines” that can negotiate the environment with humanlike ease
have yet to be developed.
The process of transforming energy in the environment into electrical energy in the neurons is called
transduction
Which of the following best describes the steps of the perceptual process?
The sequence of steps is dynamic and constantly changing.
Kimmy is casting shadows on the wall and watching whether her cat Tiger jumps at the shadows or not. She uses different hand motions to see if there is a difference in whether Tiger jumps or not. Kimmy is informally studying which relationship?
the stimulus-perception relationship
As used in the textbook, the “DL” is the abbreviation for
differenze limen
Which of the following methods are used to measure the quantitative relationship between the stimulus and perception?
classical psychophysical methods
The theory that accounts for response criterion in a detection experiment is
signal detection theory
Our perception of the environment depends on
both the properties of the environmental objects and properties of the electrical signals in the nervous system
Jan tries to focus on the tip of her pencil as she brings it closer to her. She feels the strain on her eye as she does this. What she is feeling in her eye is due to the process called
accommodation
The visual pigment molecules are contained in the
outer segments of the visual receptors.
The blind spot is located
where the optic nerve leaves the eye.
Rushton demonstrated that the physiological mechanism behind dark adaptation is
visual pigment regeneration
The difference in charge between the inside and the outside of the nerve fiber when the nerve is at rest is _____ mV.
a. –70
Rods and cones synapse with ______ cells, which then synapse with ____ cells.
bipolar; ganglion
_________: Limulus :: ________: human retina.
. Lateral plexus; horizontal and amacrine cells
The inability of lateral inhibition to explain White’s illusion suggests that some contrast effects are based in
the cortex.
The flow of information in the LGN is best described as
bi-directional, with signals coming from the retina and the cortex to the LGN
As we travel farther from the retina, neurons fire to
more complex stimuli.
When you stare at a grating of wide bars for 55 seconds, then look at a grating with narrow bars, the narrow bars will
seem to be thinner than they actually are
Which of the following proposed representational systems is the least likely to actually be in place in the human visual system?
Specificity coding
Discuss four reasons why it is important to study perception.
It is important to study perception to gain valuable knowledge of the environment. Understanding the environment we live in,
knowing how to better interact with the environment and adapting to environmental stimulus are essential to our survival.
Learning perception may also help us to develop our knowledge of other subject areas such as medicine, computing science and how to improve those areas for the betterment of human life.
Name and describe three classical psychophysical methods.
The three classical psychophysical methods are: Methods of limits, method of adjustment and method of constant stimuli.
In the method of limits, the experimenter presents stimuli by increasing or decreasing intensity. The experimenter continues to increase or decrease the intensity ( ascending or descending order) until the participant cannot detect the stimulus.
In the method of adjustment, the stimulus is also increased or decreased until the participant can just detect the stimulus. But, in the case of the method of adjustment, the participant ( and not the experimenter as it is the case with the method of limits) is the one who adjusts the stimulus intensity until the participant can just barely detect the stimulus.
In the method of constant stimuli, the experimenter is the one who presents stimuli with different intensities and in a variety of order. Each time the experimenter presents the stimulus, the participant confirms or declines seeing the stimulus. Also, the experimenter ensures the intensities varies from a lowest intensity that cannot ever be detected by the participant and the highest intensity that can always be detected by the participant.
(a) Discuss the major differences between the rods and the cones.
(b) Describe two retinal disorders that differentially affect the rods and the cones.
The major differences between rods and cones are:
Rods are more sensitive to dark, which means that 20-30 minutes after a room is dark, rods are functioning better and vision is dark-adapted. Also, rods do not have colour vision. Rods and cones are also distributed distinctively in the retina, with rods being more predominant in the peripheral retina ( although there are also cones located in this area).
Cones are more sensitive to light, they are also responsible for vision acuity ( or detailed vision). Cones are more predominant in the fovea, a small area in the retina that contains only cones ( although cones can be found in other areas as well).
Macular degeneration is a disorder in which the some areas of the retina stop functioning creating a blind region in the vision. The region is in the center which is the fovea and surround which is an area full of cones.
retinitis pigmentosa is a condition that attacks rods and result in poor peripheral vision.
Describe the process of synaptic transmission. Include in this description the differences between excitatory and inhibitory transmitters.
When an action potential reaches the end of the neuron axon, there is a small space between the neurons called synapse. When this action signal reaches the synapse, the nerve impulse causes a chemical called neurotransmitter to be released. The neurotransmitter flows into the receptive sites of the receiving neuron and if the neurotransmitter shape matches the shape of the receptor site, an electrical signal is activated in the receiving neuron. However, this signal can be either excitatory or inhibitory. If the signal is excitatory, it causes the inside of the neuron to become more positive. If the transmitter causes an inhibitory response, the inside of the neuron becomes more negative. A more positive neuron may generate an action potential.
