Sensation Flashcards
Introspection
A systematic examination of subjective mental experiences that requires people to inspect and report upon the content of their thoughts
What Is Cognition
All forms of knowing and awareness such as perceiving, conceiving, remembering, judging, reasoning, imagining and problem solving.
ie; the study of mental functions such as intelligence, thinking, language and memory
Dualism
The mind and body are of separate essence but they can influence and interact with one another. Th relationship is not one directional
Sensation
The detection of external stimuli and the transmission of this information to the brain
Perception
the processing, organisation and interpretation of sensory signals
Bottom-Up Processing
Perception based on physical features of the stimulus i.e.; you see it the way that it is
Top-Down Processing
How knowledge, expectations and past experiences influence our interpretation of sensory signals
Sensory Coding
Sensory receptors translate the physical properties of stimuli into patterns of neural impulses
Transduction
The process by which sensory stimuli are converted into signals that the brain can interpret
Vision
STIMULI- Light Wave
RECEPTORS; Light sensitive cones and rods in the retina of the eye
PATHWAY- Optic Nerve
Hearing
STIMULI- Sound Wave
RECEPTOR- Pressure sensitive hair cells in the cochlea of the inner ear
PATHWAY- The auditory nerve
Taste
STIMULI- Molecules dissolved in fluid on the tongue
RECEPTOR- Cells in tastebuds on the tongue
PATHWAY- Portions of facial glossopharyngeal and vagus nerves
Touch
STIMULI- Pressure on Skin
RECEPTOR- Sensitive ends of touch neurons on skin
PATHWAY- cranial nerve (above neck), spinal nerve (touch elsewhere)
Smell
STIMULI- Pressure on Skin
RECEPTOR- Sensitive ends of the olfactory mucous neurons in the mucous membranes
PATHWAY- Olfactory Nerve
Anatomical Coding
The receptors (in eyes, ears etc.) are connected to specific parts of the brain. When those parts of the brain are activated, the source of stimulation is clear
Temporal Coding
Different stimulation gives rise to different rates of activity in the receptor i.e., bright or low light
Absolute Threshold
The minimum intensity of a stimulation to occur before you experience a sensation. Its the stimulus intensity that you would experience 50% of the time
Difference Threshold
The minimum amount of change for a person to detect a difference between two stimuli
Weber’s Law
The just noticeable difference between two stimuli based on a proportion of the original stimulus rather than on a fixed amount of difference
Signal Detection Theory
A theory of perception based on the idea that the detection of a stimulus requires a judgement and is not an all or nothing process
Sensory Adaption
A decrease in sensitivity to a constant level of stimulation i.e. the sound of the fridge humming
Fechner
He originated three methods for threshold measurement-
The method of limits
The method of constant stimuli
The method of adjustment
Synesthesia
Unusual combination of the senses i.e. associating sounds with certain colours
Retina
The thin inner surface of the back of the eyeball, which contains the sensory signals that transduce light into neural signals
Rods
Retinal cells that respond to low levels of light and result in black and white perception
Cones
Retinal cells that respond to higher levels of light and result in colour perception
Fovea
The center of the retina where cones are densely packed
Audition
The sense of sound perception
Sound Wave
A pattern pf changes in air pressure during a period of time; it produces the perception of sound
Prosopagnosia
The inability to recognise faces
Gestalt Principles
The brain uses innate principles to group sensory information into organised wholes -Proximity
-Similarity
- good continuation
- closure
-illusory contours
- common fate
Object Constancy
Correctly perceiving objects as constant in their shape, size, colour and lightness, despite raw sensory data that could mislead perception
Binocular Depth Cues
Cues of depth perception that arise from the fact that people have two eyes
Monocular Depth Cues
Cues of depth perception that are available to each eye alone
Binocular Disparity
A depth cue; because of the distance between the two eyes, each eye receives a slightly different retinal image
Convergence
A cue of binocular depth perception; when a person views a nearby object, the eye muscles turn the eye inwards
Motion Parallax
A monocular depth cue observed when moving relative to objects, in which the objects that are closer appear to move faster than the objects that are farther away.
Eardrum
A thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate
Vestibular Sense
Perception of balance determined by receptors in the inner ear
Place Coding
The soundwave is encoded by the location of the hair cells along the basilar membr ane
Supertaster
Amplified sense of taste
Olfactory Epithelium
A thin layer of tissue within the nasal cavity that contains the receptors for smell
`Presbyopia
A condition that emerges as you age when the lens hardens so it becomes more difficult to focus on close images
Photopigments
Protein molecules that become unstable and split apart when exposed to light
Ganglion Cells
-The first neurons in the visual pathway with axons
- During the process of seeing, they are the first neurons to generate action potentials
Ventral Stream
-Occipital lobe to the temporal lobe
- Specialised in perception and recognition of objects, colour and shape
Dorsal Stream
- Occipital lobe to the parietal lobe
- Specialised in spatial perception i.e. determining what an object is and relating it to other objects in a scene
Object Agnosia
The inability to recognise objects
Trichromatic Theory
Colour vision results from activity in three types of cones that are sensitive to different wavelengths
Opponent Process Theory
Red and green are opponent colours as are yellow and blue. When you stare at one colour for too long, the receptors become fatigued and you automatically see the other one
Hue
-Distinctive characteristics that place a particular colour in the spectrum i.e. a colours greenness
- Depend on lights dominant light wave when it reaches the eye
Saturation
Purity of the colour i.e. pastels are less pure as they have a number of wavelengths
Lightness
- The colours perceived intensity.
- Determined by how much light reaches the eye
Stereoscopic Vision
The ability to determine an objects depth based on that objects projection to each eye
Occlusion
A near object blocks an object that is farther away
Relative Size
Far off objects project a smaller retinal image than close objects, if the far off and close objects are of the same physical size
Familiar Size
Because we know how large familiar objects are, we can tell how far away they are by the size of their retinal images
Linear Perspective
Seemingly parallel lines appear to converge in the distance
Texture Gradient
As a uniformly textured surface recedes, its texture continuously becomes denser
Position relative to horizon
All else being equal, objects below the horizon that appear higher in the visual field are perceived as being farther away and objects above the horizon that appear lower in the visual field are perceived as being further away
Stroboscopic Movement
A perceptual illusion that occurs when two or more slightly different images are presented in rapid succession
Motion Aftereffects
-When you gaze at a moving image for a long time and then look at a stationary scene
- You experience a momentary impression that the new scene is moving in the opposite direction from the moving image
Amplitude
Determines its loudness
Frequency
- Determines its pitch
- Measured in Hertz
Cornea
- Eye’s outer layer
- Focuses the incoming light
Lens
- Light is bent further inward and focused to form an image on the retina
Iris
- Determines the eye colour
- Controls the pupils size
Pupil
- Determines how much light can enter the eye by dilating and contracting
Eardrum
A thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate
Ossicles
Three tiny bones often known as the hammer, anvil and stirrup
Oval Window
Membrane located in the cochlea
Vestibular Sense
Perception of balance determined by receptors in the inner ear
Fast Fibers
Sharp, immediate pain
Slow Fibers
Chronic, dull, steady pain
Myelinated Axons
Can send information quickly
Non- Myelinated Axons
Send information slowly
