Psych 100 Midterm

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107 cards   |   Total Attempts: 184
  

Cards In This Set

Front Back
What does grey matter refer to?
The cortex is referred to as grey matter, because its cells are not wrapped in a fatty white sheet (myelin).
What does white matter refer to?
The inner parts of the brain that are wrapped in a fatty white sheath are often called white matter.
Compare and contrast sensation and perception.
Sensation is picking up the stimuli in the environment and is the process of gathering information from the environment. Perception is organizing and selection the senses, it is how you interpret the sensations.
Define the Just Noticeable Difference.
The just noticeable difference is the smallest difference between two similar stimuli that can be distinguished.
Contrast Weber's Law, Fechner's Law, and Stevens' Power Law.
Weber's Law: The minimum change in intensity/length/weight goes up as its intensity goes up.
Fechner's Law: each JND represents an equal step in the psychological magnitude of a sensation.
Stevens' Power Law: different numbers were assigned to sensations of different magnitudes - can study sensation over a great range.
Explain the contributions of signal detection theory to our understanding of perception.
Signal Detection Theory: every stimulus requires discrimination between Signal(stimulus) and noise(background stimuli and random activity of nervous system).
Describe how the psychological attributes pitch, loudness and timbre arise in the auditory system and the physical characteristics of sounds to which they correspond.
Pitch - Frequency, Loudness- Amplitude, Timbre - Complexity
Contrast the functions of the dorsal and ventral streams of cortical processing in vision.
Dorsal - Where pathway - enables us to perceive location of objects so we can do correct actions to those objects (ie. catch a ball)
leads to the upper occipital and parietal lobes.
Ventral - What pathway * identify objects and give meaning to them goes to the temporal lobe
Describe how perceptual disorders arise from damage to brain regions involved in visual processing.
Damage to ventral pathway leads to visual agnosia.Types of visual agnosia:Form Agnosia - can't identify shapesVisual Object Agnosia - know shape, not objectProsopagnosia - can't identify human faces
What is the fusiform face area? (FFA)
It's an area of brain activated specifically by faces.
Describe lateral inhibition and its role in helping the brain 'find edges' of objects.
In the retina, when one receptor gets excited, its neighbour gets excited as well. With lateral inhibition, edges or boundaries become intensified.
Describe the concept of the receptive field and how receptive fields contribute to perception.
Answer 12
When the activity of cell changes by being onset or offset by light - we call this the receptive field.
Excitation is when light shines on the middle of the cell. Inhibition is when light stops shining on its outside.
Describe how perception of a visual object differs from the raw sensory (retinal) image.
When an image lands on your retina, it is an inverted mirror image (upside-down, and left-right reversed). The image projected is 2D, but you must make it 3D. There's also a blind spot, where the axons form the optic nerve, so we don't actually see anything. But your brain fills in the details at the perceptual level.
What are perceptual constancies and why are they useful?
Depth perception is intimately connected with perceptual constancy. This means that we can maintain a perceptual judgment as the external stimulus changes.

Ex:
Size constancy: even though visual image of object changes with distance - our perception of that object's size does not.
Visual Constancy: visual features of stimuli remain perceptually constant.
Lightness constancy: brightness constancyShape constancy:size

Helmholtz suggests that all of these theories are due to unconscious inferences performed by the visual system. IT assumes that the information contained in the stimulus is insufficient to generate the full perceptual response.
Compare structuralist, Gestalt, and constructivist (knowledge-based accounts) of perception.
Structuralist - perception is the joining together of elementary sensations
Gestalt - whole was not necessarily equal to sum of its parts - there can be a level of pattern and order at the whole that is not simply accounted for by examining each of its parts in isolation.