Sensation and Perception Flashcards
(97 cards)
Sensory Receptors
•Specialized neurons that respond to specific types of stimuli
Occurrence of Sensation
- Sensation occurs when sensory information is detected by a sensory receptor
- Example – light that enters the eyes causes the chemical changes in cells that line at the back of the eye. These cells relay messages, in the form of action potentials, to the nervous system
- Not all sensation result in perception
Transduction
•The conversion from sensory stimulus energy to action potential
What are our senses?
- Vision
- Hearing (audition)
- Smell (olfaction)
- Taste (gustation)
- Touch (somatosensation)
- Vestibular Sense (balance)
- Proprioception and Kinesthesia (body position and movement)
- Nociception (pain)
- Thermoception (temperature)
Absolute Threshold
- Refers to the minimum amount of stimulus energy that must be present for the stimulus to be detected 50% of the time
- Generally measured under incredibly controlled conditions in situations that are optimal for sensitivity
- May be influenced by motivation, experience and expectations
Difference Threshold (jnd)
- The minimum difference in stimulation that a person can detect 50% of the time.
- Changes depending on the stimulus intensity
Weber’s Law
•The difference threshold is a constant fraction of the original stimuli
Perception
•Refers to the way sensory information is organized, interpreted, and consciously experienced
Bottom-up Processing
•Refers to the fact that perceptions are built from sensory input
Top-down Processing
•Interpretations of those sensations that is influenced by our available knowledge, our experiences, and our thoughts
Sensory Adaption
•Individuals often don’t perceive stimuli that remain relatively constant over prolonged periods of time
Inattentional Blindness
•The failure to notice something that is completely visible due to lack of attention
Signal Detection Theory
•Ability to identify a stimulus when it is embedded in a distracting background
Muller-Lyer Illusion
- Lines appear to be different lengths although they are identical.
- Arrows at the ends of the lines may make the lines appear longer or shorter
Amplitude
•The height of a wave measured from the highest point on the wave (peak or crest) to the lowest point of the wave (trough)
Wavelength
- Length of a wave from one peak to the next
* Directly related to the frequency at a given wave form
Frequency
- Refers to the number of waves that pass a given point in a given time period
- Often expressed in terms of hertz (Hz), or cycles per second
- Longer wavelength will have lower frequencies, and shorter wavelength will have higher frequencies
Electromagnetic Spectrum
- Encompasses all the electromagnetic radiation that occurs in our environment
- Includes gamma rays, x-rays, ultraviolet light, visible light, infrared light, microwaves and radiowaves
Wavelength of Light (ROYGBIV)
- Our experience of Red is associated with longer wavelengths
- Greens have intermediate wavelengths
- Blue and violets are shorter in wavelengths
Amplitude of Light
- Associated with our experience of brightness or intensity of color
- Larger amplitudes appearing brighter
High-frequency Sound Waves
•Perceived as high-pitched sounds
Low-frequency Sound Waves
•Perceived as low-pitched sounds
Audible Range of Sound Frequencies
- Between 20Hz and 20000Hz
* Greater sensitivity to those frequencies that fall in the middle of this range
Amplitude of Sound Waves
- Higher amplitudes are associated with louder sounds
* Loudness is measured in terms of Decibels (dB)