1.6 Sensation

Sensation begins when _____ reach our ______

Environmental stimuli; sensory organs

The environmental stimuli that reaches our sensory organs are converted into ______

Neural signals

The process of converting environmental stimuli into neural signals requires the stimuli to ______ before being detected and processed by the brain

Meet certain thresholds

Absolute threshold is the:

Minimum stimulus intensity detected 50% of the time

The minimum sugar in a gallon of water you can taste 50% of the time is one teaspoon

Which concept is demonstrated above?

Absolute threshold

The just-noticeable difference is the:

Smallest detectable change in stimulus intensity

Joseph tells his father to turn up the volume of the TV, one notch at a time, until he notices a slight volume increase on the radio

Which concept is demonstrated here?

Just-noticeable difference

Sensory adaptation refers to:

Decreased sensitivity to constant stimulation

After staying for 10 minutes in a bakery, the initial strong smell of cookies in the bakery fades

Which concept is demonstrated above?

Sensory adaptation

Our senses rarely work:

Alone

Senses team up through:

Cross-modal processing, sensory interaction, and synesthesia

Cross-modal processing combines:

Multiple senses

A visual input (lip movement for "ga") alters auditory perception (sound of "ba"), resulting in hearing "da"

Which concept is demonstrated above?

Cross-modal processing

Food flavor is largely determined by smell; block your nose, and a jelly bean tastes like sugar water

Which concept is demonstrated here?

Sensory interaction

Sensory interaction enhances:

Overall perception

Synesthesia is when senses:

Overlap

When Tom imagines the letter A, he always imagines it in the red color

Which concept is demonstrated above?

Synesthesia

If an observer responds to a present signal, then it is a:

Hit

If an observer responds to an absent signal, then it is a:

False alarm

If an observer does not respond to a present signal, then it is a:

Miss

If an observer does not respond to an absent signal, then it is a:

Correct rejection

A tumor is present, and the doctor correctly identifies it on the scan

Which concept is demonstrated above?

Hit

A tumor is not present, but the doctor still identifies it as present on the scan

Which concept is demonstrated here?

False alarm

A tumor is present, but the doctor does not identify it on the scan

Which concept is demonstrated above?

Miss

A tumor is not present, and the doctor does not identify it on the scan

Which concept is demonstrated above?

Correct rejection

Our sensory systems are attuned to detecting:

Changes in stimulation

Our sensory systems are not attuned to detecting:

Constant levels of stimulation

Our sensory systems being attuned to detecting changes in stimulation helps us to notice:

Important environmental changes

Our sensory systems being attuned to detecting changes in stimulation helps us to conserve:

Energy

Our sensory systems being attuned to detecting changes in stimulation helps us to conserve energy by:

Reducing responses to ongoing stimulation

Weber’s law governs how we:

Detect differences

The just-noticeable difference is proportional to:

Stimulus intensity

______ are needed to detect differences in stronger stimuli

Larger changes

Weber’s law applies across:

Different sensory modalities

Enoch easily notices a gram added to an empty bag but not to a 50-pound bag

Which concept is demonstrated above?

Weber’s law

Adaptation helps us to tune out:

Constant background noise

Adaptation helps us to stay sensitive to:

New or changing stimuli

Sensory adaptation allows us to adjust to:

Different environments

Adaptation allows us to optimize sensory processing for:

What’s happening now

The brain ______ to create coherent experiences

Integrates information from multiple senses

Integration of info from multiple senses happens:

Automatically and continuously

Integration of information from multiple senses enhances our ability to:

Understand and navigate environment

Common sensory interactions include:

Taste (smell + visual), speech comprehension (auditory) + lip movements (visual) , balance (vision + auditory)

Synesthesia is a form of:

Sensory interaction

During synesthesia, one sensory experience ______

Triggers another

Associations during synesthesia are:

Consistent and automatic

Experiences during synesthesia can involve ______ combination of senses

Any

Experiences during synesthesia can boost:

Memory and creativity

What is this called?

Iris

What is this called?

Cornea

What is this called?

Conjunctiva

What is this called?

Pupil

What is this called?

Lens

What is this called?

Retina

What is this called?

Fovea

What is this called?

Optic nerve

The retina serves as the:

Primary visual receptor

The retina converts ______ into ______

Light into neural signals

The retina contains:

Multiple cell layers

The cell layers in the retina begin _______ before the visual information reaches the brain

Processing visual information

Initial visual processing includes detecting:

Light intensity, basic edge and motion, and color processing

Color processing happens in _____ areas

Cone-rich

After initial visual processing, the ______ makes up for retinal limitations

Brain

After initial visual processing, the brain makes up for retinal limitations by filling in the:

Blind spot

After initial visual processing, the brain makes up for retinal limitations by maintaing:

Perceptual stability

After initial visual processing, the brain makes up for retinal limitations by integrating information from:

Both eyes

The lens adjust to:

Focus images on retina

The lens focusing images on retina is called:

Accommodation

The lens changes shape for:

Near and far vision

The pupil size adjusts for:

Light intensity

Eye muscle coordinates for:

Binocular vision

Examples of vision problems:

Myopia, hyperopia, astigmatism

Myopia is when images focus:

In front of retina

Myopia is also called:

Nearsightedness

Hyperopia is when images focus:

Behind retina

Hyperopia is also called:

Farsightedness

Astigmatism is caused by:

Irregular cornea shape

An irregular cornea shape causes:

Distortion

Mr. Davis, a 65-year-old high school teacher, has recently noticed that he struggles to read the student essays on his desk. He can see the students at the back of the classroom clearly, but anything up close appears blurred and out of focus. A trip to the ophthalmologist confirms that the structure of his eye responsible for focusing light has become less flexible with age. 

Which eye structure is involved here?

Lens

Maria walks from a brightly lit school hallway into a dark theater to watch a play. Initially, she cannot see well because her pupils were constricted (small) to protect her eyes from the bright light. In the darkness, her pupils will soon dilate (expand) to allow more light to enter the eye and reach the retina, which improves her vision in low-light conditions.

Which part of the eye is responsible for this?

Pupil

Sarah closes her left eye and stares at a cross mark on a piece of paper held at arm's length. A few inches to the right of the cross is a small dot. As she slowly moves the paper closer to her face, keeping her right eye fixed on the cross, the dot suddenly disappears from her peripheral vision at a certain distance

Which concept is demonstrated above?

Blind spot

A student watches her school bus approach from a quarter-mile down the street. Although the image of the bus on her retina gets larger and larger as it gets closer, she does not perceive the bus as physically "growing" in size. Instead, she perceives it as a normal-sized bus that is simply getting nearer.

Which concept is demonstrated above?

Perceptual stability

Maria holds her pointer finger out at arm's length. She closes her left eye and notes the position of her finger relative to a distant object. When she opens her left eye and closes her right eye, her finger appears to jump to a different position. The brain uses this difference (disparity) in the two images to calculate how far away her finger is.

Which concept is demonstrated above?

Binocular vision

Fourteen-year-old Sarah is sitting at the back of her history classroom and cannot clearly read the words written on the whiteboard, but she can perfectly read the textbook on her desk

Which concept is demonstrated above?

Myopia

Sarah, a 45-year-old high school teacher, is grading papers one evening. She can see her students at the back of the classroom clearly during the day and has no issues driving. However, when she tries to read the comments she has written on the papers in front of her, the words appear blurry and out of focus. To read them clearly, she has to hold the papers at arm's length. After an hour of grading, she develops a headache and eye strain. 

Which concept is demonstrated above?

Hyperopia

Mrs. Thomas is reading a newspaper and notices that some lines of text appear clear while others, particularly those at a different angle (e.g., vertical vs. horizontal), look blurry or smeared. When she looks at a circle of lines radiating like a star some lines look darker and clearer than others

Which concept is demonstrated here?

Astigmatism

Rod cells give us vision in:

Low light

Rod cells are crucial for detecting movement in our:

Peripheral vision

Rod cells ______ as lighting conditions change

Adapt significantly

Light adaptation happens ______ when entering bright areas

Fast

When entering bright areas, rod sensitivity:

Decreases

When entering bright areas, cone cells become:

More active

When entering bright areas, the pupil ______

Constricts

When entering bright areas, the pupil constricts to:

Reduce light entry

Dark adaptation is ______ than light adaptation

Slower

Dark adaptation involves ______ rod senstivity

Increased

Dark adaptation involves ______ cone activity

Reduced

Dark adaptation involves pupil ______

Dilation

Dark adaptation involves ______ regeneration

Rhodopsin

Sarah is walking home late at night. The streetlights are dim, and the environment is mostly dark.Sarah can still see the general shapes of trees and buildings along the street. When a cat darts across the path in her peripheral vision, she immediately notices the movement

Which part of the eye is responsible for these sights?

Rod cells