Lecture 1 Intro
How can we measure mental processes?
We can manipulate stimuli and infer mental processing from behavior (with cleverly designed experiments)
In terms of action potentials, higher pressure on a touch receptor causes what to happen to it?
Increases its firing rate
At what stage of the perceptual process do dreams and hallucinations happen?
Neural processing
Perception requires _______ because the basic signal from our sensory organs is ________.
Perception requires inference because the basic signal from our sensory organs is ambiguous.
Describe the two types of attention
Iconic memory (visual)
Echoic memory (auditory)
What did the cognitive map experiment show?
Rats didn't behave based on previously reinforced behavior, they instead adjusted their behavior based on a cognitive map of their environment. Refutes behaviorism
What are 2 types of excitatory input? What do they do?
1) Excitatory neurotransmitters 2) transduction
They increase the likelihood of a neuron firing
Name 4 examples of plasticity
1) Adapting to cochlear implants
2) Recovering from strokes
3) Changes in the homunculus
4) Learning to read braille
Describe Broadbent's filter model. + What class of models is it in?
Information goes into sensory memory, then filtered based on physical characteristics, then the detector processes the meaning of whatever we're attending to
Early selection models
Name the two forms of guidance of overt attention, and an example of each
Top-down processing: knowledge, expectations,task and goals, schemas
Bottom-up processing: visual salience based on things like color, contrast, motion, orientation
Describe 2 neural findings with respect to sensory memory and working memory
Working memory central executive is supported by prefrontal cortex
Sensory memory is caused by persistent neural firing in perceptual areas
Why did behaviorists dislike introspection?
- Varies person to person
- Unverifiable
What are the 3 levels of analysis for cognition? What about for neuroscience?
Cognition: Subjective internal experiences, behavior, physiology
Neuroscience (aka physiology): Neurons, brain regions, networks
List the steps of the perceptual process
- Stimulus in the environment
- Stimulus property transmitted to sensory organs
- Neural processing
- Conscious perception
- Recognition
- (Action)
Describe the load theory of attention, and the accompanying experiment on distraction
Load Theory of Attention consists of:
•Processing capacity: how much information a person can handle at any given moment
•Perceptual load: the difficulty of a given task
•Experiments suggest that it’s easier to get distracted during low-load (easy) tasks because there is remaining processing capacity to get captured by distractors
Describe the different components of eye movements, what they form when considered together, and how they are measured
Together, they form a scanpath: the series of fixations and saccades one makes on a given stimulus
Eye movements are measured using eyetracking
Name and describe the components of the Modal model, and what parts have been updated/aren't quite correct
Sensory memory: initial stage that holds all incoming information for seconds or fractions of a second
Short-term memory: holds five to seven items for about 15 to 20 seconds
Long-term memory (LTM): can hold a large amount of information for years or even decades
Control processes: active processes that can be controlled by the person
Updated: short-term memory is now an umbrella term for sensory memory and working memory (Modal model's "short term memory" essentially = today's working memory)
Modal model is not 100% correct: evidence now indicates that STM and LTM can function separately
Name 4 early psychologists we discussed and what they did
Donders: one of the first cognitive experiments
Wilhelm Wundt: analytic introspection
William James: Introspection
John Watson: Behaviorism
Edward Tolman: Cognitive maps (rats in mazes)
Noam Chomsky: Argued against behaviorism based on children's language learning
Ulric Neisser: The first cognitive psychology textbook
What are the 3 ways in which we can localize function? + for each one, name 1 example of a specific function that was localized
Neuropsychology: examining what specific type(s) of functioning decline when certain areas of the brain are damaged
Examples: Broca's aphasia, Wernicke's aphasia, hemispatial neglect
Neuroimaging: fMRI, PET
Examples: fusiform face area, extrastriate body area
Psychophysiology: EEG, MEG, ECoG
Examples: ECoG used to localize homunculus
Name 5 examples of top-down influences on perception (general categories, or specific findings)
General categories:
•Knowledge, Memory, Goals, Expectations, Reward and motivation
Specific findings:
- McGurk effect (lips moving changing what you hear)
- Odor pleasantness influenced by knowledge
- Flavor influenced by expectations
- Pain influenced by placebo
Name and describe 4 theories of how we resolve perceptual ambiguity
•Structuralism: our perception results from just the adding up of sensory information
•Gestalt psychology: the whole is different than the sum of its parts
Next 3 are all in the general category of likelihood theories:
•Likelihood principle: We perceive what is most likely to have caused our sensory experience
•This process typically happens unconsciously so it has also been called unconscious inference
•Bayesian inference: we make inferences by combining our pre-existing beliefs and knowledge with current evidence
- Prior, likelihood, inference
Describe spatial neglect, the circumstances in which we can overcome it, the area that is damaged in it, and the specific stage of attentional processing that is malfunctioning
Describe Baddeley's model and 3 experiments supporting it
Phonological loop (verbal & auditory working memory), visuospatial sketchpad (visual & spatial working memory), central executive (attention controller: Focus, divide attention, switch attention, suppression of irrelevant information
Experiments:
- Articulatory suppression: supports phonological loop
- Phonological similarity supports phonological loop
- Mental rotation supports visuospatial sketchpad
Describe Donder's reaction time experiment:
1) The goal of the experiment
2) The tasks used
3) The specific strategy to infer the cognitive process of interest
1) Understand how long it takes people to make decisions
2) Simple RT task and choice RT task
3) Decision time = choice RT - simple RT
- Describe how feature detectors can lead to experience
- Describe the logic of standard neural analyses vs decoding
Different neurons prefer different stimuli (e.g., different orientations of bars), so we can tell what we’re experiencing (e.g., viewing) based on which neurons are firing
Standard analysis: Determine how stimuli influence neural activity: compare activity between different stimuli
Decoding: Reconstruct or classify the stimuli using the neural activity: Figure out the information contained in brain activity
Note that decoding often relies on feature detectors
As we move along the ventral stream, visual features that are processed become: __________
Name 3 conditions caused by damage to the visual stream, and what specific areas are damaged
As we move along ventral stream, visual features that are processed become more complicated
1) Visual form agnosia (lateral occipital complex)
2) Alexia (visual word form area)
3) Prosopagnosia (fusiform face area)
Describe early and late selection models, and evidence for each
•Early selection models: attention is needed to process meaning; attention filters information before meaning is processed. (You’re selecting what to attend to early on in processing)
Evidence:
- Dichotic listening experiment: people can't report meaning of sentences in the unattended ear
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•Late selection models: Selection of stimuli for final processing does not occur until after meaning has been processed. You’re selecting what to attend to late in processing
Evidence:
- Cocktail party effect
- (another) Dichotic listening experiment: the meaning of attended words unconsciously influences behavior
Name 5 things that covert attention does
Covert attention alters appearance (more colorful, brighter, sharper, etc)
Covert attention alters which brain regions are involved in processing visual information
Covert attention influences what spatial regions of the world are represented in your visual brain regions
Covert attention changes what a given neuron responds to
Covert spatial attention is likely involved in deciding where to move our eyes
Describe 4 experiments used to understand sensory memory or working memory capacity or duration, and what they found
Sensory memory:
- Whole vs partial report procedure (Sperling) shows that sensory memory is only limited by duration, not capacity
- Counting backwards experiment showed that working memory worsens over time due to decay and interference
- Digit span shows the capacity of working memory is typically 5-8 items
- Change detection shows that working memory capacity is also dependent on the complexity/amount of information per item