Unit 3 Test: Sensory and Perception

sensation

the process by which the nervous system detects the physical world

perception

the process by which the nervous system organizes and interprets sensory information (a cognitive process)

3 steps required for a physical stimulus to be perceived

1. detect the physical stimulus
2. transduction
3. deliver to proper destination in the brain

Sensory Transduction

the conversion of physical stimulus into neural impulses and action potentials for the brain to interpret

Bottom-Up Processing

perception that begins with the sensory receptors and input, working up to the brain's integration

Top-Down Processing

perception that begins with higher-level mental processes and is guided by experience and expectations

Sensory Adaptation

the process of adjusting to physical stimulus that is unchanging

Psychophysics

the study that relates the physical characteristics of a stimulus to the psychological experience

Absolute Threshold

the smallest quantity of sensory input that can still be detected 50% of the time

Difference Threshold (just-noticeable-difference, jnd.)

the smallest change in sensory input that can still be detected 50% of the time

What is Weber's Law?

the idea that to be perceived as different, two stimuli must differ by a constant, minimum percentage.

What is the Weber constant?

K - the constant percentage by which two stimuli must differ to be perceived as different

Signal-Detection Theory

a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation

Sensory Coding

how the qualities of the sensory input are translated into specific representations within the nervous system

Specificity Theory (of Sensory Coding)

the theory that sensory coding is labeled-line coding, where different neurons correlate to different sensory characteristics

Pattern-Theory (of Sensory Coding)

the theory that sensory coding is based on patterns of neurons, where some fire more or less to correlate to different sensory characteristics

Selective Attention

our tendency to focus on just a particular stimulus among the many that are being received

The cocktail party effect

being able to focus attention to one particular stimulus amidst an abundance of other stimuli

Inattentional Blindness

the phenomenon where if one is not actively looking or paying attention to a stimulus, then they are blind to it

Change Blindness

the phenomenon where one is blind to change when they are NOT paying attention to certain details

Perceptual Set

a mental predisposition to perceive something in a particular way due to expectations, prior knowledge, or context

What factors influence Perceptual Set?

priming, context, culture, and emotions