Exam 2 Miller + Smith Flashcards
What is Cognitive Science
The interdisciplinary study of the mind and its processes; Study of intelligent behavior; The brain mechanisms and computations underlying that behavior.
The Major movements in the history of Cognitive Science
1800s- Mind not an object of (scientific) study
1800-1840 - Phrenology
1880 - 1920s - Structuralism
1913 - 1960s - Behaviorism
1950s - Cognitive Revolution
1970s- Cognitive Neuroscience
Before the 1800s
Major Figures
Rene Descartes and William James
Key Legacy: Mind body problem
1800- 1840 Phrenology
Frank Joseph Gall
Pseudoscience
Measures skull to infer about the brain and mind
Legacy: Brain areas have specific local functions.
1880s - 1920s Structuralism
Key Figures: Wilhelm Wundt (1st Psych Lab)
Edward Titchener
Key Legacy: Break down things into elements
Methods of analytical introspection.
1913- 1960s Behaviorism
John Watson
B.F. Skinner
Ivan Pavlov
Legacy: Focus on behavior (Operant conditioning)
1950s- Cognitive Revolution
Noam Chomsky (1959) criticized Skinners book
Argued language is biologically innate
Children say things and are never rewarded,
Information Processing
Likened the mind to a computer
Thought of processing info in a series of stages and both have limited capacity.
Cognitive Science
The mind can and should be studied
Goal= understand how our experience are represented in the mind and brain
Measurement (Recording)
Reveal Brain regions associated with certain mental processes/ behaviors
Assess correlations between brain and behavior
Correlation
Perturbation (causal) techniques
Require changing the brain
Access causal relationships
What is the difference between special and temporal resolution?
3 Measurements/ recordings
FMRI
PET
EEG
Functional Magnetic Resonance Imaging
How does it work?
1. Brain is activated
2. Associated part gets blood for oxygen
3. FMRI reads different magnetic properties
Subtraction Method
(Condition A - Condition B)
Resting state functional connectivity measures how closely FMRI signals in diff region track each other in the absence of an experimental task
Advantages and Disadvantage of FMRI
Advantages: Good spatial resolution
Noninvasive
Disadvantages: Poor temporal resolution
Expensive, loud disruptive. Can’t move.
Positron Emission Tomography
How does it work?
1. Radioactive Ligands injected into body
2. Ligands bind to relevant receptor
3. Machine detects gamma rays
Advantages and Disadvantages of PET
Advantages: Distribution/ degree of neurotransmitter signaling
Can detect early onset of diseases
Disadvantages :
Very poor temporal resolution
Very expensive and invasive
Electroencephalography (EEG)
How does it work?
1. Scalp electrodes worn by participant
2. Brain produces electric activity
3. Signals are averaged over trails to create Event Related Potential (ERPS)
Advantages and disadvantages of EEG
Advantages
Good Temporal resolution
Direct measure of neural activity
non invasive; inexpensive
Relatively mobile and feasible for infants
Disadvantages: poor spatial resolution
Perturbation (stimulation
Assess causal relationships
Requires changing the brain
Ex. Naturally occurring lesions
TMS
How do we study Naturally Occurring Lesions?
- Major event causes lesion
- Brain examined to identify lesion
- Behavior studied to identify changes and effects
Pros and Cons of NOL
Advances: powerful for inferring causality
Disadvantages: legions are often not focal
Patients can be difficult to find
Can’t induce legions
Transcranial Magnetic Stimulation
How does it work?
1. Emits magnetic pulses
2. Pulses converted to electrical current
3. Inhibits or excites particular function
What is stimuli?
Physical Phenomena that interacts with sensory organs
Ex. Light waves, sound waves, volatile chemicals
What are sensory receptors?
Cells within sensory organs with specific process purposes
Ex. Rods/cones, olfactory nerves
Transduction
Translation of a stimulus into neural signals transmitted to the brain.
Excite or inhibit action potentials
Sensation
The interacting with the physical stimuli of the world
Perception
the Cognitive experience of the stimuli, involves elaboration and interpretation of sensory stimuli
Sensation of a green light
Stimulus= Green light
Sensory organ = eye
Sensory Receptors = photoreceptors
Sensation of Stimulus
Effect of stimulus on sensory receptors.
Translation of stimulus into neural signals that are transmitted to the brain
Turned into chemical and electrical signals
The processing and interpreting into mental representation
What is transduction?
Transduction = translation of stimulus into neural signals transmitted to the brain.
What is sensation?
Sensation= Interaction with physical stimulus of the world.
What is perception?
Perception= cognitive experience of stimuli
What are the two sensory receptors involved in vision?
- Cones
- Rods
Where are the rods and cones located?
Cones are located in the center of the retina
Rods are located in peripheral
What sensory receptor is more sensitive during the day?
Cones are more sensitive during the day
What receptor is more sensitive during the night?
Rods are more sensitive at night.
How do light waves travel through the brain to trigger changes In MP?
From Light waves to the brain.
1. Light goes through optic nerve
2. Lens is able to refract light and bend light to put it in focus
3. Light converted on rods and cones
4. APs in ganglion created
5. APs sent down membrane
What is the receptive field?
Small area of photoreceptors respond (visual field). Fovea is densely packed with cones and correspond to outer part of visual field, have high spatial resolution. Outside= less dense; more peripheral less spatial resolution, corresponds to outside area of visual fields.
Center-surround organization
Light falling on center of reception field leads to activation
Light off center leads to inhibition
Off-Center On-Surround
Light falling on center of reception field leads to inhibition
Light off center leads to activation
What is the first part of the brain that the optic nerve projects to?
The optic nerve projects to the lateral Genicular Nucleus (LGN) which projects to primary visual cortex.
What are the two streams of the visual system?
Dorsal stream
Ventral stream
What is the dorsal stream?
“Where” pathway involved in spatial perception allows us to spatially locate objects. Originates in V1 and extends into posterior parietal cortex ( and ultimately dorsal front context)
What is the ventral stream?
“What” pathway, object detection analyzes shape, texture ID. Extends into anterior temporal lobe
How does information processing become more complex via hierarchical coding hypothesis?
Things are processed in stages, as stages go up everything becomes more complex. Neurons coding for more rudimentary features synapse onto neurons coding more complex features.