Sensation and Perception Exam 2

Occlusion is a "monocular" depth cue that can tell you

What objects are closer to you than other objects

Complete the part of online activity 6.1 "Relative Height". In Image 3, you perceive the red cube as being further away than the blue cube because ____.

It is higher up on the screen

Which of the following best describes what happens when you look at something far away?

Your eyes turn outward slightly

When we view the world with two eyes, if an object is not on the horopter, the light from the object will land on each retina in a different location. As the difference between these locations grows, ____.

The object appears further from the horopter

When experiencing binocular rivalry, you will likely see

Two different images appearing to 'compete' with each other from whichever eye is dominant

How does the Viet-Müller circle relate to the horopter?

The Vieth-Müller circle is an imaginary geometric circle that approximates the horopter, but the two are not always the same.

Activity 6.2 demonstrates how our visual system uses binocular disparity to perceive depth (stereopsis). As you shift your focus from one object to another, the relative positioning of objects on each retina changes. Based on this principle, what happens when you shift your focus from a nearer object to a farther one?

The object you were originally focused on appears to move outward on each retina, while the new focal object aligns more closely between both eyes.

Which of the following is not a depth cue that can be perceived with just one eye (monocular depth cue)?

Horopter

The correspondence problem refers to how the brain determines which parts of an image in one retina correspond to the same parts in the other retina. Based on Marr & Poggio's constraints, which of the following best explains why this problem is solvable?

Each point in the world maps uniquely to only one point in each retina, and nearby points tend to have similar depths.

With only one eye, our perception of the world is different from reality because:

The projection of a three-dimensional scene onto a two-dimensional retina distorts spatial relationships.

In a visual search task, adding more distractors will make you slower and slower to find the target, unless it is a ____.

Simple feature search

Complete all parts of Online Activity 7.3 including the "conclusion". You are able to see the particular target scenes so quickly in these videos by ____.

Identifying the typical spatial structure of each scene

A person with visual neglect due to parietal damage in the right hemisphere will be blind in their left visual field.

False

Attention changes the way the brain process incoming visual information in ____ visual areas.

Early

Mid-Level

Parietal

All of the above

The attentional blink experiment demonstrates that if you perform a task that requires attention to a letter in the RSVP stream, you will not be able to see letters occurring ____.

About 200 ms after the letter

A radiologist is so busy searching for a tumor in their patient's occipital lobe that they completely fail to notice a piece of metal lodged in the frontal lobe. This is a real-world example of what concept?

Inattentional blindness

Response enhancement means a neuron becomes more selective by reducing its response to irrelevant information to filter out noise and make the target pop out.

False

Which of the following is a characteristic of feature binding according to Feature Integration Theory?

It requires focused attention to be processed.

In the Posner Cuing Task, what happens when a cue is valid?

Reaction time (RT) speeds up because attention is correctly directed.

A feature search is efficient because:

The target is defined by a single unique feature

Motion refers to a change in _____ over time.

Spatial position

Which of the following is an example of apparent motion?

A hand-drawn animated movie

The motion direction of a single object alone can provide information about global motion patterns.

False

When a professional athlete is determining when to extend their hand to catch a ball, when are they subconsciously calculating?

Time to collision (TTC)

Which of the following eye movements can occur voluntarily?

Saccade

If a person is living with akinetopsia, what would they experience when watching cars driving on a road?

A disjointed series of snapshots of other cars

Complete the Activity 8.5 (Distinguishing Eye from Object Movements), What occurs when there is no retinal movement, but the eyes are moving?

The object is being tracked with smooth pursuit eye movement

CompleteActivity 8.1(all parts), Why does the system fail to detect motion when the spot moves too fast?

The delay cells activate too late, preventing multiplication cells from firing.

Why does placing an aperture around some of the dots change the perception of motion?

The aperture restricts the visible portion, leading the brain to interpret the motion differently.

How does neural adaptation contribute to the motion aftereffect (MAE) illusions?

Neurons tuned to the viewed motion direction become fatigued, reducing their response.

Our experience of sound is caused by changes in the atmospheric pressure of air around us.

True

Complete Online Activity, "The Audibility Curve", Which frequency required the lowest amplitude to be heard in this experiment?

4000

The number of times a sound wave goes up and down in one second determines the ___ that we perceive, and the size of the change from up to down determines the ___.

Pitch; loudness

A trumpet sounds different than a saxophone, even playing the same note, due to difference in their ____.

Harmonic frequencies

The structure known as the "middle ear" acts to ____.

Connect the ear drum to the inner ear

Amplify incoming sounds

Dampen the response to very loud incoming sounds

All of the above

Because the basilar membrane has different qualities (shape, width) along its length, it responds maximally to different ____ at different places along its length.

Frequencies

Which of the following structures is the first to receive auditory nerve input after sound is transduced in the cochlea?

Cochlear Nucleus

What is the primary function of hair cells in the cochlea?

Converting mechanical movement into neural activity

What is the primary reason neurons cannot phase-lock to frequencies higher than 1000 Hz?

Neurons cannot fire action potentials fast enough

Why is amplification by the ossicles necessary for hearing?

More energy is required to move fluid in the cochlea than to move air

How do people resolve the ambiguity caused by cones of confusion?

By moving their head to introduce new ITD and ILD cues

How does the Doppler Effect relate to echolocation?

It informs about the motion of objects based on shifting frequencies

The interaural time difference is largest when a sound comes from _____.

Your side

CompleteOnline Activity 10.5, both the Introduction and Phonemic Restoration. These demonstrations show that our auditory system tries to figure out when a sound has been interrupted, or masked by another sound, and fills in the missing sound information for us.

True

What is the purpose of the musical helix model?

To combine tone height and chroma in one structure

Because the interaural level and time differences used by the brain to localize sound rely critically on knowing the shape of your head and your ear, young children have difficulty localizing sounds because their head and ears are smaller than the brain assumes they will be.

False

If the fundamental frequency is missing from a harmonic sound, what do listeners perceive?

The same pitch as if the fundamental were present

What is auditory stream segregation?

The ability to distinguish between different sound sources in an environment

Which aspect of speech makes computer recognition more difficult?

Coarticulation and contextual variability

The McGurk effect shows that visual information has no influence on how we hear speech sounds.

False

Binocular Summation

Combining two noisy pictures of something gives more info than one alone

Binocular Disparity

Difference between two retinal images of the same scene

Bigger the disparity, the closer the object is

Depth Cues

Information about a third dimension of space

Binocular Rivalry

Two eyes receive incompatible inputs that switch between dominance

Monocular Depth Cues

Only using one eye

Occlusion

Relative Size

Text Gradients

Occlusion

Depth based on order

Nonmetrical, only gives relative position of objects

Relative Size

We assume smaller objects are further away

Aerial Perspective

More light that's scattered, the further away things are

Linear Perspective

Parallel lines in a 3d image will converge to a point in the retina

Vanishing Point

The point where the lines appear to converge

Anamorphosis

Use of linear perspective to create a two-dimensional image so distorted that it only looks correct from a certain angle

Motion Parallax

During movement, close things will sweep across the retina more quickly than distant things

Horopter

Location of objects whose image lie on corresponding points

Vieth Muller Circle

Location of objects whose images fall on corresponding points in two retinas

Horopter Disparity

The larger the disparity, the further something away is

Accomodation

Lens in eye changes shape to focus nearby

Convergence

Eyes rotate inward when focusing at difference

Focus on nearer objects

Divergence

The ability of two eyes to turn outward

Focus on further objects

Uniqueness

Each point in world is only one point on each retina

Each point in one retina must have exactly one point in the other

Continuity

Nearby points probably have similar depth values

Stereoblindness

Inability to make use of binocular disparity as a depth cue

Stereoacuity

Measure of smallest binocular disparity that can generate a sensation of depth

Dichoptic

Presentation of two stimuli, one to each eye

Strabismus

Misalignment of the eyes

One eye captures in the fovea, the other has it in the non-fovea

Attention

Process that whittles down, filters out, and selects small subset of incoming information for processing

Attentional Selection

Process of choosing what to attend

Feature Integration Theory

Attention is needed to glue features of an object together

Attention is limited by a bottleneck

Priority Map

Brain first gathers basic features

Enhances relevant color features

Enhances shape features

Features combine into a priority map, where the most relevant object gets the highest activation

Response Enhancement

Neuron increases firing rate

Sharper Tuning

Neuron becomes more selective, reducing response to irrelevant information

Altered Tuning

Neuron actually shifts preference to better match the attended stimulus

Inhibition of Return

Once you've attended a location, you have a hard time returning to that location

Visual Search

Finding target stimulus among distractor stimuli

Efficient Search

Operates in parallel

Inefficient Search

Requires serial processing

Guided Search

Basic features narrow down search set, then serial search within that set

Visual-Field Neglect

Inability to respond to stimuli in a portion of space

Results from damage to parietal lobe

Extinction

Patient can perceive stimuli in impaired field if presented alone

Soap Opera Effect

When the number of images per second in the video doesn't match the display's number of images per second

Delay Neuron

Neuron delays signal in one eye so that both eyes perceive at the same time

Is checked by a multiplication cell

Reichardt Detector

Delay neuron ensures the circuit is direction-sensitive

More neurons, more fluid the motion

Aperture Problem

Not enough information, so the brain makes an educated guess

Placing an aperture around dots changes perception of their movement

Global Motion

Movement for large, rapidly moving objects

Differential activation in the magnocellular layers of the LGN

Local Motion

Fine, subtle movements detected in the center of vision

Differential activation in the parvocellular layers of the LGN

First Order Motion

Motion is defined by changes in luminance

Second Order Motion

Motion in an object that occurs due to changes in texture in the absence of motion

Used in camouflage

Optic Flow

Changing angular positions of points so that they simulate how we move through the world

Comes from Focus of Expansion FOE), the center of the horizon

Biological Motion

Movement patterns produced by living organisms

Humans are good at detecting biological motion, even when only a few points are available

Tau (Time to Collision)

As something approaches, its size grows on the retina in a structured way

Motion-Induced Blindness

Stationary targets in the periphery will disappear when global moving pattern is superimposed

Also known as troxler effect