Topic 1: Introduction to Perception Flashcards
(49 cards)
In what terms can perception be described in?
can be defined in terms of sensory processes, like receptor activation and neural firing
or in terms of mental activity that mediates between sensation and awareness, interpreting what our senses tell us (subjective experience)
What is the definition of sensation?
process of encoding energy or chemicals in the environment in terms of neural signals
a basic experience elicited by a simple stimulus
more concerned with your own physical experience (ego centric)
e.g. feeling of warmth on your skin
What is the definition of perception?
organization and interpretation of neural signals, making them meaningful
more complex conscious experiences produced by integrating sensations
more concerned with identifying the stimulus
e.g. you see a glowing red stove element, producing heat you feel; you know it is 50 cm away, and it can burn you
Why do we study perception for understanding?
to determine how underlying mechanisms function
first step in understanding cognition (e.g. mind-body relationship)
to know why the world looks. sounds, feels, tastes, and smells the way it does
Why do we study perception to solve practical problems?
to develop solutions for the sensory impaired (e.g. Braille, glasses)
to understand the practical applications of illusions
to produce substitutes for the world (e.g., stereo sound, surround sound)
to produce substitutes for the observer (e.g. robotic vision)
What is the central problem in perception?
the world is three-dimensional
the image on our retina is 2-D
yet we think of the world in 3-D
this problem is called underdetermination
What is a distal stimulus?
the object in the world
e.g. an apple, a finger poking your arm, a vibrating string
What is a proximal stimulus?
the pattern of energy or chemicals impinging on our receptors
e.g. pattern of photons on your retina; kinetic energy on your skin; sound energy hitting your eardrum
How do we go from an underdetermined proximal stimulus produced by a distal stimulus, and arrive at a correct perception of the world?
not enough info in the proximal stimulus at our sensors to tell you what a distal stimulus actually is
2-D retinal image of an apple –> percept of 3-D apple
there are many possible interpretations of the proximal stimulus
different answers to this question define different schools of thought in the study of perception
What is structuralism?
goals: analyze conscious processes into basic “elements”; specify how elements become connected
Wilhelm Wundt: first psychology lab
Edward Titchener relied on introspection: analysis of one’s own conscious experience
What is the problem with structuralism?
perception is holistic, not elemental
can’t break down your conscious experience
What is Gestalt psychology?
opposed structuralism: decomposition to elementary components loses information
was a holistic approach that emphasized consciousness
goal: specify the relationship among stimuli
motto: “the whole is different than the sum of its parts”
founded by Max Wertheimer
What is constructivism?
perceiving is an active process, affected by our knowledge and experience
we must interpret ambiguous information provided by the environment
computations over internal representations yield percepts
Hermann von Helmholtz, Irvin Rock, Richard Gregory
What is the ecological approach?
we should study perception in natural settings
enough information is available in the environment to make mental calculations unnecessary
J.J. Gibson: proposed information is directly picked up from the government
What is the computational approach?
assumes the mind is an information processor that receives, stores, retrieves, transforms, and transmits information
David Marr: defined vision mathematically, using computer simulations
information processing has three levels of analysis: computational theory, representation and algorithm, and hardware implementation
What is computational theory?
what is the system doing?
e.g. what does it mean to “see” something?
What is representation and algorithm?
what is the percept? how is it being processed?
e.g. do the eyes function like cameras? is there an “inner screen” in our heads?
What is hardware implementation?
what physical “machinery” does this?
e.g. what neural circuits allow us to see?
What is the neurophysiological approach?
based on reductionism: understanding of behavior via studying the underlying biological processes
important for sensation, less effective for perception
Perception
the experiences that result from stimulation of the senses
Sensation
often identified with elementary processes that occur at the beginning of a sensory system
Perceptual Process
a sequence of steps leading from the environment to perception of a stimulus, and action with regard to the stimulus
Distal Stimulus
the stimulus “out there”, in the external environment
Proximal Stimulus
the stimulus on the receptors
in vision, this would be the image on the retina
