Psych Unit 1.6-2.1

Sensation

is the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.

Perception

is the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.

Bottom-up processing

• analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information (sensation first)

Top-down processing:

• information processing guided by higher-level mental processes , as when we construct perceptions drawing on our experiences and expectations (experience first)

transduction

The process of converting one form of energy to another or, in this case, converting sensory stimulation into neural signals

Signal detection theory

predicts how and when we  detect the presence of a faint stimulus amid background stimulation, thus assuming there is no single absolute threshold and that detection depends on the person. 

subliminal

Stimuli you cannot consciously detect 50% of the time

Priming

is a phenomenon in which exposure to one stimulus influences how a person responds to a subsequent, related stimulus.

absolute threshold

is the minimum amount of stimulus energy needed to detect a particular stimulus 50% of the time.

difference thresholds

note the minimum difference between two stimuli required for detection 50% of the time. 

Weber’s law

states that, to be perceived as different, two stimuli must differ by a constant percentage rather than a constant amount.

Sensory adaptation

is diminished sensitivity as a consequence of constant stimulation or exposure.

wavelength

(distance from the peak of one wave to the next)

hue

(color)

(height)

determines the intensity

intensity

(the amount of energy the wave contains)

cornea

(the eye’s clear, protective layer)

pupil

(adjustable opening of the eye allowing light to pass through)

iris

(colored ring of muscle tissue)

lens

(transparent structure which changes shape to focus images)

retina

(the light sensitive inner surface of the eye with layers of neurons to convert light into neural impulse, step 2 of transduction)

accommodation.

These neural impulses are carried to the brain via the optic nerve

Feature detectors

are nerve cells in the visual cortex respond to specific features, such as edges, angles, and movement.

Parallel processing

refers to our ability to analyze many aspects of a problem (or in this case, a sensation) simultaneously.

Sensorineural hearing loss

• (a.k.a. Nerve deafness): inability to hear due to damage to the cochlea’s receptor cells or to the auditory nerves

Conduction hearing loss

inability to hear due to damage to mechanical elements of the ear (parts other than the cochlea)

Place theory

states that the pitch of a sound we hear is due to activation of specific hair cells on the basilar membrane (like a piano).

Frequency theory

states that the entirety of the basilar membrane vibrates in response to sound, and the speed of the vibration is how we perceive pitch (like a drum). 

Gate-control theory

states that the spinal cord acts as a buffer between pain and the brain, deciding which signals will pass through; pain is a function of the balance between the information traveling into the spinal cord through large nerve fibers and information traveling into the spinal cord through small nerve fibers.

phantom limb sensations

after a limb amputation. Without normal sensory input, the brain may misinterpret and amplify spontaneous but irrelevant central nervous system activity.

Olfaction,

or our sense of smell, is also a chemical sense and works closely with taste through a process called sensory interaction (when one sense influences another)

Gustation

 or our sense of taste, is a chemical sense.

Sensory interaction

refers to the ability of one sense to influence or interact with another.

embodied cognition

the influence of bodily sensations, gestures, and other states on cognitive preferences and judgments. 

selective attention

 

Frankly, some information isn’t important. Therefore, we rely on selective attention, or focusing our conscious awareness on a particular stimulus.

cocktail-party effect

refers to the ability to focus one's attention a particular stimulus while filtering out a range of other stimuli

inattentional blindness

Failing to see visible objects when are attention is focused elsewhere is known as

change blindness.

Failing to notice changes in the environment

Figure-ground

is the organization of the visual field into objects (figures) that stand out from their surroundings (the background). 

depth perception. 

From two-dimensional objects falling on our retinas, we somehow organize three-dimensional perceptions that allow us to estimate that object’s distance from us.