Chapter 4: Sensation and Perception Flashcards
Sound Waves
Changes in air pressure
Pure tone
Simple sound wave that consists of regularly alternating regions of higher and lower air pressure, radiating outwards in all direction from the source.
Three dimension of Sound waves
Frequency, amplitude and complexity.
Frequency
the repetition rate of the sound wave depends on how often the peak in air pressure passes the ear. Perceived as the pitch: how high or low a sound is.
Amplitude
The intensity relative to the threshold for human hearing.
Loudness
The perception of a sounds intensity.
Complexity
Mixture of frequencies, influences perception of timbre.
Timbre
The quality of sound that allows you to distinguish two sources with the same pitch and loudness.
Outer Ear
Collects sound waves and funnels them towards the middle ear. The pinna, the auditory canal, and the eardrum.
The Middle Ear
A tiny, air-filled chamber behind the ear drum with the ossicles.
Ossicles
Mechanically transmits and amplifies vibrations in fluid waves, from the eardrum to inner ear by pushing against the oval window.
The inner ear
The cochlea, basilar membrane, and hair cells.
Cochlea
A fluid filled tube that contains cells that transduce sound vibrations into neural impulses.
Basilar Membrane
A structure in the inner ear that moves up and down in time with vibrations related from the ossicles, transmitted through the oval window. Where the sound hits indicates its frequency.
Place code
The brain uses information about the relative activity across the whole basilar membrane to help determine the pitch you hear.
Timbre
The relative amounts of different frequency components, relative activity of hair cells across the whole basilar membrane.
Temporal Code
The brain uses the timing of the action potentials in the auditory nerve to help determine the pitch you hear.
Conductive Hearing Loss
The eardrum or ossicles are damaged to the point that they cannot conduct sound waves to the cochlea.
Sensorineural Hearing Loss
Damage to the cochlea, hair cells, or the auditory nerve. happens as we age.
Cochlear Implant
Can restore hearing by replacing the function of the hair cells. Stimulate the auditory nerve.
Haptic Perception
The active exploration of the environment by touching and grasping objects with our hands.
Tactile Receptive Field
Small patch of skin that relates information about pain, pressure, texture, pattern, or vibration to a receptor.
A-Delta Fibre
Axons that transmit initial sharp pain.
C Fibres
Slow axons that transmit the longer-lasting, duller persistent pain.
Referred Pain
Sensory information from the internal and external areas converges on the same nerve cells in the spinal cord. (heart attack pain in left arm)
Gate-Controlled Theory
Signals arriving from pain receptors in the body can be stopped or gated by interneurons in the spinal cord via feedback from the skin or from the brain. (rubbing the affected area)
PAG
region in the midbrain that sends inhibitory signals to the neurons.
Proprioception
Your sense of bodily position
Vestibular System
three fluid-filled semicircular canals and adjacent organs located next to the cochlea in each inner ear.
Odurants
Chemicals that make their way into our noses.
Olfactory Epithelium
A mucous membrane in the nasal cavity with contain olfactory receptors.
Olfactory bulb
A brain structure located above the nasal cavity beneath the frontal lobe.
Pheromones
Biochemical odorants emitted by other members of an animal’s species that can affect its behaviour or physiology.
Flavour
Taste and Smell combined.
Sensation
The process by which stimuli are detected, transduced into nerve impulses and sent to the brain.
Perception
The brain’s interpretation of raw sensory inputs.
Transduction
The process of converting an external energy or substance into electrical activity within neurons.
Sense Receptor
Specialized cell responsible for converting external stimuli into neural activity for a specific sensory system.
Sensory Adaptation
Activation is greatest when a stimulus is first detected and then decline in responsiveness over time.
Psychophysics
The study of how we perceive sensory stimuli based on their physical characteristics
Absolute Threshold
The lowest level of a stimulus needed for the nervous system to detect a change 50% of the time.
Just Noticeable Difference
The smallest change in the intensity of a stimulus that we can detect.
Webers Law
K x I (Constant x Intensity of the Stimulus) (0.10 x intensity)
Signal Detection Theory
Theory regarding how stimuli are detected under conditions. Accuracy = Number of correct responses / Number of attempts.
Signal-to-noise Ratio
The ratio of the power of a signal to the power of background noise
Parallel Processing
The ability to attend to many sense modalities simultaneously.
Bottom Up-Processing
Processing in which a whole is constructed from parts.
Top-Down Processing
Conceptually driven processing influenced by beliefs and prior learning.
Perceptual Set
A set formed when expectation influence perceptions
Perceptual Constancy
The process by which we perceive stimuli consistently across varied conditions.
Selective Attention
The process of selecting one sensory channel and ignoring or minimizing others.
Filter Theory of Attention
Attention is a bottle neck through which information passes.
Inattentional Blindness
Failure to detect stimuli that are in plain sight when our attention is focused elsewhere.
Change Blindness
Failure to detect changes in a visual stimulus.
Extrasensory Perception (ESP)
Perception of events outside the known channels of sensation.
Precognition
Predicting events before they occur through paranormal means
Telepathy
Reading other minds
Clairvoyance
Detecting the presence of objects or people hidden from view.
Visible Light
Electromagnetic radiation between 400-700 nm.
The Cornea
Part of the eye containing transparent cells that focus light on the retina.
Myopia (nearsightedness)
Can only see close objected. Cornea is too long to focus light.
Hyperopia (farsightedness)
Can only see far objects. Cornea is too flat to focus light.
Lens
Part of the eye that changes curvature to keep images in focus.
Accommodation
Changing the shape of the lens to focus on objects near or far.
The Retina
Membrane at the back of the eye responsible for converting light into neural activity.
Rods
Allows us to see light
Cones
Allows us to see colour.
Photopigments
Protein molecules within the rods and cones whose chemical reaction when absorbing light result in nerve impulses being generated.
Optic Nerve
Nerve that travels from the retina to the brain.
Blind Spot
Part of the visual field we can;t see because of the absence of rods and cones.
The Principle fo Gestalt Psychology
Emphasized the natural organization of perceptual elements into wholes or patterns.
- Proximity
- Similarity
- Continuity
- Closure (seeing things as complete)
- Symmetry
- Figure Group Segregation.
Trichromatic Theory
Idea that colour vision is based on our sensitivity to the three primary colours.
Opponent Process Theory
Theory that we perceive colours in terms of three pairs of opponent colours.
- red or green
- blue or yellow
- black or white.
Dual process theory
The modern colour vision theory that posits that cones are sensitive to red, green, and blue.
Colour Blindness
Inability to see some or all colours.
Depth Perception
Ability to judge distance and three-dimensional relations.
Monocular Cues
Relative Size
Texture Gradient
Interposition (blocking another object)
Linear Perspective
Height in Plane
Light and Shadow
Motion Parrallax
Binocular Cues
Binocular Disparity: comparing left and right images.
Convergence: eyes converge inward to provide distance.
Blindless
The inability to see due to problems with the eye and its related structures.
Motion Blindness
A neurological disorder in which a person is not able to perceive motion.
Visual Agnosia
A failure to recognize visually presented objects.
Blindsight
The ability of individuals with blindness to detect and response to visual stimuli despite lacking awareness of having seen anything.
