Chapter 4 part 1-2 Psychology Sensation and Perception

What is sensation?

The process of receiving stimulus energies from the external environment and transforming them into neural energy.

What is perception?

The process of organizing and interpreting sensory information so that it makes sense.

What is bottom-up processing?

A method where the brain takes in sensory information at the level of individual units and combines them to understand the world.

What is top-down processing?

A method where perception, influenced by memory and expectations, affects how sensory information is organized.

What are sensory receptors?

Specialized cells that selectively detect and transmit sensory information to the brain.

What is the absolute threshold?

The minimum amount of energy an organism can detect 50 percent of the time.

What is 'noise' in the context of sensation?

Any stimulus that interferes with the perception of another stimulus.

What is a 'signal' in sensory perception?

The stimulus we are trying to sense.

What is the difference threshold?

The minimum difference in stimulus intensity necessary for detection, also known as Just Noticeable Difference (JND).

How does Weber's Law relate to JND?

JNDs are determined by the proportion of change rather than the amount of change.

What does subliminal mean?

Information below the level of conscious awareness.

What is priming?

Activating a particular concept or idea in memory so that the person is affected by that concept.

What is Signal Detection Theory?

An approach to perception that focuses on decision making about stimuli under conditions of uncertainty.

What factors can affect the detection of sensory stimuli?

Fatigue, expectations, and urgency.

What is selective attention?

Focusing awareness on a narrowed aspect of the environment.

What is the cocktail party effect?

The ability to focus on a single conversation in a noisy environment.

What is the Stroop effect?

A failure of selection where attention is attracted by conflicting information.

What is perceptual set?

A predisposition or readiness to perceive something in a particular way.

What is sensory adaptation?

A change in responsiveness of the sensory system to unchanging stimuli.

What is wavelength in vision?

The distance between wave peaks, perceived as hue.

What is amplitude in vision?

The height of a wave, perceived as brightness.

What is purity in vision?

The mixture of wavelengths, perceived as saturation.

What is the sclera?

The white, outer part of the eye.

What is the iris?

The colored muscle of the eye that controls the size of the pupil.

What is the retina?

The multi-layered light-sensitive surface that transforms light energy into neural impulses.

What are rods in the eye?

Photoreceptor cells sensitive to dim light but not color, functioning well in low illumination.

What are cones in the eye?

Photoreceptor cells that respond to color and operate best under high illumination.

What is the pathway of visual information?

Neural impulses leave the eye for the brain, with information from the right side sent to the left occipital lobe.

What is the trichromatic theory of color vision?

The theory that cones are specialized to pick up red, green, or blue.

What is the opponent-process theory?

The theory that two types of ganglion cells process color information in opposing pairs.

What is an afterimage?

A sensation that remains after a stimulus is removed.

What does Gestalt psychology focus on?

How people naturally perceive their environment, emphasizing that 'the whole is worth more than the sum of the parts.'

What is the Closure principle in Gestalt psychology?

The tendency to perceive incomplete shapes as complete.

What does the Proximity principle state?

Objects that are close together are perceived as a group.

What is the Similarity principle in Gestalt psychology?

Items that are similar are grouped together in perception.

What is depth perception?

The ability to see objects in three dimensions, despite retinal images being in 2-D.

What are monocular cues?

Depth cues that require only one eye, such as familiar size, linear perspective, and overlap.

What are binocular cues?

Depth cues that require both eyes, such as retinal convergence.

What is perceptual constancy?

The recognition that objects do not physically change despite changes in vantage point and viewing conditions.

What are the three types of perceptual constancy?

Size constancy, shape constancy, and color constancy.

What does wavelength determine in hearing?

The frequency of sound, perceived as pitch.

What does amplitude determine in hearing?

The loudness of sound, measured in decibels (dB).

What is the function of the outer ear?

The pinna funnels sound waves into the ear.

What is the role of the tympanic membrane?

It vibrates in response to sound waves in the middle ear.

What is the cochlea?

A fluid-filled structure in the inner ear that converts sound vibrations into neural impulses.

What is the Place Theory of hearing?

It states that the location of vibrations on the basilar membrane determines pitch.

What does Frequency Theory propose?

What we hear depends on the frequency of neuronal firing in the auditory nerve.

What is the Volley principle in hearing?

Clusters of neurons can fire in rapid succession, filling the gaps between impulses.

What is the pathway for hearing processing?

Cochlea → auditory nerve → brain stem → temporal lobe.

What are the skin senses?

Touch, temperature, and pain.

What are the receptors for temperature?

Thermo receptors that detect warm and cold sensations.

What is the role of endorphins in pain perception?

They can turn pain signals on and off.

What are the basic tastes detected by the tongue?

Sweet, sour, bitter, salty, umami, and fat.

What is the olfactory epithelium?

The tissue involved in the sense of smell, connected to the temporal lobe and limbic system.

What do kinesthetic senses detect?

Movement, posture, and orientation of the body.

What do vestibular senses help with?

Balance and movement, detected by the semicircular canals.

What is the significance of sensory thresholds?

They define the minimum stimulus required for detection in various senses.

What factors can affect perception?

Context, expectations, and previous experiences can influence how we perceive stimuli.

What is the outer wall of the eye called?

Sclera

What covers the iris and lens at the front of the eye?

Cornea

What connects the eye to the brain?

Optic nerve

What is the function of the retina?

It lines the inner surface of the sclera and receives light to create images.

What is the purpose of the pupil?

It is an opening in the iris that allows light to enter the eye.

Where is the upside-down image created in the eye?

On the retina

What is the fovea?

A depression in the retina that is responsible for sharp central vision.

What are the three main structures of the ear?

Outer ear, middle ear, and inner ear.

What is the exposed part of the outer ear called?

Pinna

What are the three tiny bones in the middle ear?

Hammer, anvil, and stirrup.

What is the function of the cochlea?

It converts sound waves into nerve impulses.

What is the role of the auditory nerve?

It transmits sound information from the cochlea to the brain.

What is the function of the semicircular canals?

They help maintain balance.

What is the process of visual information crossing from the eyes to the brain?

Images from the right visual field are processed in the left hemisphere and vice versa.

What does the opponent-process theory explain?

It explains color vision in terms of opposing color pairs: red-green, blue-yellow, and black-white.

What is the figure-ground relationship in visual perception?

It refers to the ability to distinguish an object (figure) from its background (ground).

What are Gestalt principles?

They are rules that describe how we organize visual elements into groups or unified wholes.

What is a texture gradient in monocular cues?

It refers to the way texture appears denser as it recedes into the distance.

How does motion perception work?

It involves the brain interpreting changes in position of objects as we move.

What are the three physical dimensions of sound?

Amplitude (loudness), frequency (pitch), and complex sounds (timbre).

What is the role of the olfactory bulb?

It processes smell information received from the olfactory receptors in the nasal passage.

What is the function of the auditory canal?

It channels sound waves from the outer ear to the eardrum.

What happens to sound waves when they reach the eardrum?

They cause the eardrum to vibrate.

What is the significance of the basilar membrane in hearing?

It contains hair cells that convert sound vibrations into neural signals.

What is the role of the tectorial membrane?

It interacts with hair cells in the cochlea to facilitate sound transduction.

What is the function of the olfactory epithelium?

It contains receptor cells that detect odorants.

What is the blind spot in the eye?

It is the area on the retina where the optic nerve exits, lacking photoreceptors.