Exam Two

Sensation, Perception, Memory, and Development

What is sensation?

The detection of physical stimuli from the environment and translating the information into neural impulses. HAS NO EFFECT ON THE INTERPRETATION OF THE EXPERIENCE

i.e. vision, temperature, touch, and smell

What is perception?

The selection of important info and construction of meaning from that info. Our conscious experience of the world.

When communicating physical stimuli our bodies must signal both quantity and quality of sensory experience. What is the quality component?

refers to the specific characteristics of a sensory experience, such as color in vision, or the type of taste (sweet, sour, etc.) in gustation.

When communicating physical stimuli our bodies must signal both quantity and quality of sensory experience. What is the quantity component?

refers to the intensity or amount of a sensory experience, such as brightness in vision or loudness in hearing.

What is the threshold?

The range of human experience, the sensory experience that we are capable of experiencing. The endpoints of the ranges of human sensory and perceptual ability.

What is the sensory threshold?

The point where a physical stimuli exerts a strong enough signal to turn on a sensory receptor.

What is the perceptual threshold?

The point where an individual goes from not being aware of a stimulus to being aware of the stimulus

True or False

Animals can have much lower or higher thresholds that humans.

True; dogs can determine trillions of more olfactorants than humans.

True or False

The sensory threshold is always larger than the perceptual threshold.

False; vice versa

What is signal detection theory?

The theory that explains how individuals detect signals amid noise, considering factors like sensitivity and decision criteria.

What are the two components of signal detection theory?

The sensitivity to the stimulus in the presence of other distactions and the criteria used to make the judgement from ambiguous info

Why is Signal Detection Theory necessary?

People lie about perceiving a stimulus because of the expectation of a stimulus.

If the stimulus is present ant the participant detects it, …

the outcome was a hit

If the participant does not detect the stimulus, …

the outcome was a miss.

If the stimulus is absent, but the participant indicates that they’ve detected it, …

the outcome was a false alarm.

If the stimulus is absent and the participant does not detect it, …

the outcome was a correct rejection.

What is the absolute threshold?

How intese does a stimulus have to be before you can detect it.

What is the difference threshold?

How much doe the intensity of a stimulus need to be changed before the change is noticeable.

What is the minimum stimulus of vision?

Candle at 30 miles away

What is the minimum stimulus of smell?

One drop of perfume defused through six rooms

What is the minimum stimulus of touch?

The wing of a fly falling on a cheek from 1 centimeter.

What is a supraminal stimuli?

Those above the threshold

If a stimuli is supraliminal to the sensory absolute threshold, the stimulus …

is sensed but not perceived.

If a stimuli is supraliminal to the perceptual absolute threshold, the stimulus …

is both sensed and perceived.

What is a subliminal stimulus?

Those below a threshold

If a stimulus is subliminal to the sensory absolute threshold, the stimuli is …

not sensed or perceived.

If a stimulus is subliminal to the perceptual absolute threshold, the stimuli is …

sensed but not perceived

What is a subliminal message?

A short term communication that is recognized by an individual’s sensory system but outside of their perception.

There are different types of neurological damage, what is blindsight?

Damage to the visual perception pathways, while leaving the amygdala in tact. As a result the individual is blind but can perceive and respond to visual stimuli such as movement.

There are different types of neurological damage, what is prosopagnosia?

Sensation with out perception, ionability ot recognize faces.

What is the difference threshold?

The bare minimum change required to sense/perceive the change 50% of the time. As more intense stimuli occur the difference threshold increase.

What is Weber’s Law?

states that the size of the just noticeable difference (JND) is a constant proportion of the original stimulus value. This means that as the intensity of a stimulus increases, a larger change is needed for the change to be noticed.

What is adaptation?

The sensory system responding less and less to constants, producing dramatic after effects. Along with difference threshold allows the brain to focus its attention to information changes.

What is transduction?

The process of translating physical sensory information to neural impulse.

What are rods and cones?

The photoreceptors fo the eye that together initiate transdution of light cells into neural impulse.

What are rods?

Photoreceptor cells in the retina responsible for vision in low light conditions. There are over 120 million of them in the retina. Not sensitive to color and proficient at seeing movement. Making up a large portion of the peripheral vision.

What are cones?

Photoreceptor cells in the retina that are responsible for color vision and function best in bright light conditions. There are about 6 million cones in the retina, concentrated in the fovea.

What is the retina?

the photosynsitive recgion of the back of eye that contains cones and rods.

What is the pupil?

A hole in the iris that opens (dilates) and closes (constricts) to control the amount of light entering the eye.

What is the lens of the eye?

A transparent structure behind the iris that focuses light onto the retina. It changes shape to help with focusing on objects at various distances.

What is the iris?

A group of muscles that dilate and constrict the pupil determining the amount of light entering the eye.

What is the aqueous humour?

A clear fluid in the eye that maintains intraocular pressure and provides nutrients to the avascular structures of the eye, such as the lens and cornea.

What is the cornea?

The clear, dome-shaped surface that covers the front of the eye. It helps to focus light as it enters the eye and provides protection.

The view of the image in the eye is what?

Inverted, thus making the brain have to perceptually flip the image.

Why is peripheral vision colorless?

Because peripheral vision relies on rod cells, which are more sensitive to light but do not detect color, and to allow use to focus on the foveal field.

How do we translate light into neural impulse?

Photorecptors have photopiigment that decomposes. This causes an action potential that goes to bipolar cells which transfer the impulse to ganglion cells. The axons of ganglion cells make up the optic nerve.

What is photopigment?

Protein molecules that breaks down in response to light and initiates the phototransduction process in photoreceptors, allowing for the conversion of light into neural signals.

What is the blindspot?

The location where the optic nerve connects to the retina, there are no photoreceptors.

Why does our vision not have a blindspot?

Our brain fills in information with surrounding information, there are other areas from inactivity or blood cells that don’t transmit a signal. They are just filled in by perception.

How does the optic nerve operate?

It goes to the primary visual cortex, the two nerves cross at the optic chiasm exchanging neural impulses to make not contralateral.

How is vision a bi-lateral process?

Vision is seen by both eyes art the same time thus the is on from each eye needs to cross tho the optic chiasm to the contralateral side.

i.e. right visual field (both eyes), left retina, right brain

The primary visual cortex initiates visual processing. What is the lower pathway?

Ventral pathway, also known as the “What” pathway, carries impulses to the lower temporal lobe where we engage in object recognition. Allowing us to known what we are looking at.

The primary visual cortex initiates visual processing. What is the upper pathway?

The dorsal pathway, also known as the “Where” pathway, carries to the parental lobe to process spatial info.

What do we mean by color does not exist?

Color is a perception created by the brain in response to different wavelengths of light; it does not exist independently in the physical world.

What color are shorter wavelengths of light (400-500nm)?

Violets & Blue

What color are medium wavelengths of light (500-600nm)?

Green & Yellow

What color are longer wavelengths of light (600-700nm)?

Orange & Red

Wha tis Trichromatic Theory?

A theory of color vision that proposes that the human eye has three types of receptors sensitive to different wavelengths of light: short (blue), medium (green), and long (red). These three types of cones work together to allow us to perceive a wide range of colors.

What are the S-cones of the Trichromatic theory?

the type of photoreceptor cells in the human eye that are sensitive to short wavelengths of light, primarily associated with the perception of blue colors.

What are the M-cones of the Trichromatic theory?

the type of photoreceptor cells in the human eye that are sensitive to medium wavelengths of light, primarily associated with the perception of green colors.

What are the L-cones of the Trichromatic theory?

the type of photoreceptor cells in the human eye that are sensitive to long wavelengths of light, primarily associated with the perception of red colors.

Certain colors like yellow can be sensitive to multiple types of cones?

M & L cones

What is the odd thing about Red Light?

At 650nm barely activates even L-cones

What is Subtractive Color Mining?

A method of color mixing where colors are created by subtracting varying amounts of light, typically using pigments. This process involves combining different colors of inks or paints to produce a desired color.

What is the Additive Color Mining?

Think stage lighting/ our eyes, stimulation of multiple cones to cause a color. This method involves mixing different colors of light, where the addition of different wavelengths creates new colors.

What is Opponent-process theory?

Suggests that in addition to having three photoreceptors that are specifically sensitive to certain wavelengths of light that lead to primary colors of blue (S), green (M), and red (L). If the image does not stimulate a cone, it suggest that it contains an opposite color.

What does the length of wavelengths determine?

The hue

What does the amplitude determine?

The brightness

What is the moment of transduction in the hearing system?

The moment when sound waves are converted into electrical signals by hair cells in the cochlea, allowing the brain to process sound.

How sound waves are heard is determined by what?

The frequency and amplitude of the wave.

What is the eardrum or tympanic membrane?

a thin membrane that vibrates in response to sound waves, transmitting sound from the outer ear to the middle ear.

What are the three bones that make up the ossicles?

The hammer, anvil, and stirrup.

What are the semicircular canals?

Three fluid-filled structures in the inner ear responsible for maintaining balance and spatial orientation.

What is the cochlea?

A spiral-shaped, fluid-filled structure in the inner ear that converts sound vibrations into neural signals for the brain.

What nerve delivers neural impulses from the cochlea to the brain?

The auditory nerve, also known as the cochlear nerve, transmits sound information from the cochlea to the brain.

What is the oval window?

The point of attachment for the ossicles where virbation causes the formation of a wave in the cochlea.

What is the first step in the process of hearing?

Soundwaves enter the ear and vibrate the eardrum

What is the second step in the process of hearing?

The vibration of the eardum causes the ossicles in the middle ear to vibrate.

What is the third step in the process of hearing?

Ossicle vibration causes oval window to vibrate making a wave to move through fluid of cochlea.

What is the fourth step in the process of hearing?

The wave in teh cochlea moves through the basilar membrane, where it causes hair cells (cilia) on top of the membrane to move and bend.

What is the fifth step in the process of hearing?

The bending of the hair cells release neurotransmitters which stimulates the auditory nerve to send a signal to the primary auditory cortex .

What is the basilar membrane?

A membrane in cochlea to hold cilia for vibration detection

What is the transition path of soundwaves?

Sound Waves to Vibration Waves to Pressure Waves

What is audition?

The sensation of hearing

What is the measurement of the sound-wave pitch?

Hertz (Hz), cycles per second

Sound is encoded in two ways, what is temporal coding?

The encoding of lower frequencies that the cilia can match up to 4,000 Hz

Sound is encoded in two ways, what is place coding?

The encoding of sound frequencies that are higher than 4,000 Hz, based on the location of activated hair cells along the cochlea. This allows us to perceive signals of higher frequency sounds.

Wha tis localization of sound?

The ability to identify the origin of a sound in space, using cues such as interaural time differences and interaural level differences. The ears do not determine sound, the brain perceives it.

What is interaural time difference?

The difference in arrival time of a sound between two ears, which helps in determining the direction of the sound source.

What is interaural intensity difference?

The difference in sound pressure level reaching each ear, which aids in localizing the sound source based on which ear receives a louder signal.

True or False

Differences in the origin of sound can occur straight on

False; differences in sound can only occur from angles to the left or right, not directly in front or behind.

What is the inner ear?

The cochlea, semicircular canals, and vestibule. It is responsible for the vestibular sense; hearing and balance.

How does the semicircular canals function?

They detect rotational movements of the head, helping to maintain balance and spatial orientation. By having liquid that moves as the head is bent.

How does taste occur?

It is a chemical process where molecules from doos stimulate tast receptors within tase buds, and action potential goes to the thalamus to the frontal lobe. Taste also relies on the sense of smell, touch, and texture.

What are the five basic taste sensations?

They are sweet, sour, salty, bitter, and umami.

True or False:

The tongue is divided into regions for taste.

False; the tongue is not divided into distinct regions for taste. All areas of the tongue can detect the five basic taste sensations.

What is a supertaster?

A supertaster is an individual who has a heightened sensitivity to certain tastes, particularly bitter flavors, due to a higher density of taste buds. This can affect their food preferences and dietary choices.

What is the olfactory system?

The system for smell.

What is gustation?

Taste

What stimulates olfactory receptors?

Olfacotrants of which there are 350 protein receptors fro in the human body.