PSY 207 Test #1
Chapter 1: Introduction to Cognitive Psychology
Cognitive Psychology
Definition: The scientific study of mental processes such as perception, memory, reasoning, and language.
Example: Studying how people interpret language or make decisions.
Key Terms:
Introspection
Definition: The process of examining one's own conscious thoughts and feelings.
Example: Describing your emotions after reading a sad story.
Limitation: Unreliable and subjective as it depends on personal interpretation.
Behaviorist Movement
Definition: Focused on observable behavior and dismissed the study of internal mental processes.
Example: B.F. Skinner’s studies on operant conditioning.
Key Point: More reliable methods but couldn't explain internal thoughts.
Transcendental Method
Definition: The approach to studying internal mental states by observing behavior and making inferences.
Example: Inferring someone's thought process by observing how they solve a problem.
Connection: Rooted in Immanuel Kant’s ideas.
Response Time (RT)
Definition: The time it takes for a person to respond to a stimulus.
Example: Measuring how quickly a person presses a button after a math problem.
Cognitive Neuroscience
Definition: A field that studies the brain's role in cognition through neuroimaging and related techniques.
Example: Using fMRI to see brain activation while solving problems.
Clinical Neuropsychology
Definition: The study of brain-damaged individuals to understand cognitive functions.
Example: Studying patient HM to understand memory.
Neuroimaging Techniques
Definition: Tools for measuring brain activity and structure.
Examples:
fMRI: Measures brain activity through blood flow.
EEG: Records brain’s electrical activity.
CT Scans: Show brain structure using X-rays.
Tolman
Example: Conducted experiments on rats and latent learning. Rats navigated mazes without rewards and later used that knowledge to find food, showing learning occurred even without reinforcement.
Chomsky
Example: Argued against Skinner’s theory of language acquisition, asserting that humans have an innate capacity for language.
Bartlett
Definition: Developed the concept of schema (organized bodies of knowledge) to help make sense of new information.
Example: People recall a story differently depending on their schemas (expectations) about the story.
Gestalt Psychology
Definition: Focuses on how people perceive objects as wholes rather than just sums of parts.
Example: Perception of a triangle when you only see three edges of it.
Chapter 2: Brain and Neuropsychology
How to Study the Brain
Methods include neuroimaging (fMRI, PET) and studying individuals with brain damage (clinical neuropsychology).
Key Terms:
Amygdala
Function: Processes emotions, especially fear.
Example: Reacting to a threat triggers the amygdala.
Prefrontal Cortex
Function: Responsible for decision-making, planning, and impulse control.
Example: Involved in reasoning before making a major life decision.
Hindbrain
Function: Regulates essential functions like balance, heart rate, and breathing.
Example: Damage to the hindbrain can result in difficulty walking and breathing.
Cerebellum
Function: Coordinates voluntary movement and balance.
Example: Affects fine motor skills like writing.
Midbrain
Function: Processes auditory and visual information.
Example: Allows you to quickly turn your head toward a sound.
Forebrain
Function: Involved in higher functions like thought, emotion, and memory.
Example: Includes the thalamus and hypothalamus.
Thalamus
Function: Serves as a relay station for sensory information.
Example: Sensory information passes through the thalamus before reaching the cortex.
Hypothalamus
Function: Regulates basic survival behaviors (e.g., hunger, temperature regulation).
Example: Stimulates hunger when blood glucose is low.
Corpus Callosum
Function: Facilitates communication between the left and right hemispheres.
Example: Damage can cause difficulties in tasks that require both hemispheres to work together.
Lesion
Definition: Brain damage in a specific area.
Example: Studying lesions in the hippocampus helps us understand its role in memory.
Neglect Syndrome
Definition: Ignoring half of the visual field due to brain damage.
Example: A person with right hemisphere damage may ignore objects on their left side.
Agnosia
Definition: The inability to recognize objects despite normal sensory processing.
Example: Apperceptive agnosia (can’t recognize objects due to a failure in perceptual processing).
Aphasia
Definition: Language impairments caused by brain damage.
Example: Wernicke’s aphasia – difficulty understanding spoken language.
Apraxia: Disturbance in the initiation of organized or voluntary action
Agnosia
Disruption in the ability to identify familiar objects
Apperceptive agnosia: can see the features of an object (like color and shape) but can’t put those together to see the object as a unified whole. (bottom-up processing).
Associative agnosia: can see the object, and can put the features of the object together, but cannot connect the object to the knowledge of the world (top-down processing).
Aphasia
Disruption to language ability
Neurons
86 billion nerve cells in the brain
Cell body
Also known as soma
Dendrites
Receives signals from other neurons
They pick up neurotransmitters released by other neurons
Axon
Sends signals away from the neuron
Can be extremely long
Synapse
Space between neurons
Neurotransmitters are released into here
Cortex
Definition: The outer layer of the brain, involved in many complex functions such as thought, memory, and consciousness.
Example: The cerebral cortex is responsible for processing sensory information, decision-making, and problem-solving.
Convolutions
Definition: The folds and grooves on the surface of the brain, which increase the surface area of the cerebral cortex.
Example: The brain's convolutions allow for a greater amount of cortical area to fit within the skull.
Longitudinal Fissure
Definition: The deep groove that divides the brain into two hemispheres (left and right).
Example: It runs from the front to the back of the brain and is the largest fissure in the brain.
Cerebral Hemisphere
Definition: One of the two halves of the brain (left and right), each responsible for different functions.
Example: The left hemisphere is typically associated with language and logical tasks, while the right hemisphere is linked to creativity and spatial awareness.
Frontal Lobes
Definition: The part of the cerebral cortex located in the front of the brain, involved in decision-making, problem-solving, and control of behavior.
Example: The frontal lobes are responsible for voluntary muscle movements and cognitive functions like planning.
Central Fissure
Definition: The groove that separates the frontal and parietal lobes.
Example: The motor cortex is located just in front of the central fissure.
Parietal Lobes
Definition: The region of the brain located at the top and rear, involved in processing sensory information, particularly touch and spatial awareness.
Example: The parietal lobes allow you to recognize how your body is positioned and help with understanding where objects are in space.
Lateral Fissure
Definition: The deep groove that separates the temporal lobe from the frontal and parietal lobes.
Example: The lateral fissure is important for the division of brain regions that specialize in different functions.
Temporal Lobes
Definition: The part of the brain located on the sides, associated with processing auditory information, language comprehension, and memory.
Example: The temporal lobes are involved in understanding spoken language and storing long-term memories.
Occipital Lobes
Definition: The part of the brain located at the back, primarily involved in visual processing.
Example: The occipital lobes help you recognize shapes, colors, and the movement of objects.
Subcortical Structures
Definition: Brain structures located beneath the cerebral cortex, involved in basic life functions, emotion, and memory.
Example: Includes structures like the thalamus, hypothalamus, amygdala, and hippocampus.
Limbic System
Definition: A group of structures in the brain involved in emotion, motivation, and memory.
Example: The amygdala and hippocampus are part of the limbic system and are crucial for emotional responses and memory formation.
Commissures
Definition: Bundles of nerve fibers that connect the left and right hemispheres of the brain.
Example: The corpus callosum is the largest commissure and allows communication between the two hemispheres.
Event-Related Potentials (ERPs)
Definition: Brain responses that are the direct result of a specific sensory, cognitive, or motor event.
Example: An ERP might be recorded when a person hears a sound or sees an image, and it reflects the brain's immediate response.
Fusiform Face Area (FFA)
Definition: A region in the temporal lobe specialized for facial recognition.
Example: The FFA helps us identify and differentiate faces from one another.
Transcranial Magnetic Stimulation (TMS)
Definition: A non-invasive technique that uses magnetic fields to temporarily stimulate or inhibit brain activity in specific areas.
Example: TMS is used to investigate the role of brain areas in cognition and treat conditions like depression.
Localization of Function
Definition: The idea that specific areas of the brain are responsible for particular cognitive functions.
Example: The Broca’s area is responsible for speech production, while Wernicke’s area is involved in language comprehension.
Primary Motor Projection Areas
Definition: Areas of the cerebral cortex that send signals to muscles to control movement.
Example: The motor cortex in the frontal lobe is involved in voluntary muscle movement.
Primary Sensory Projection Areas
Definition: Areas of the cerebral cortex that receive and process sensory information.
Example: The somatosensory cortex in the parietal lobe receives information about touch and pain.
Contralateral Control
Definition: The principle that each hemisphere of the brain controls the opposite side of the body.
Example: The left hemisphere controls movements of the right hand, and the right hemisphere controls the left hand.
Association Cortex
Definition: Brain regions that integrate information from multiple senses and are involved in higher cognitive functions such as thinking and decision-making.
Example: The prefrontal cortex is an association cortex involved in planning and reasoning.
Apraxia
Definition: A motor disorder characterized by difficulty in executing voluntary movements, despite having no paralysis.
Example: A person with apraxia might be unable to button a shirt or wave goodbye, even though they understand the task.
Glia
Definition: Support cells in the brain that assist with neuron function, including nutrient supply and waste removal.
Example: Glial cells outnumber neurons and play a role in maintaining brain health.
Neurotransmitter
Definition: Chemical messengers that transmit signals across synapses between neurons.
Example: Dopamine is a neurotransmitter involved in reward and pleasure systems.
Presynaptic Membrane
Definition: The membrane of the neuron that releases neurotransmitters into the synapse.
Example: When an action potential reaches the axon terminal, it triggers the release of neurotransmitters from the presynaptic membrane.
Postsynaptic Membrane
Definition: The membrane of the neuron that receives neurotransmitters from the synapse.
Example: Neurotransmitters bind to receptors on the postsynaptic membrane to initiate a response.
Threshold
Definition: The minimum level of stimulus required to trigger an action potential in a neuron.
Example: If the depolarization of the neuron reaches the threshold, it will fire an action potential.
Action Potential
Definition: A rapid electrical impulse that travels along the axon, triggered when the neuron's membrane potential reaches the threshold.
Example: The action potential is essential for communication between neurons.
Myelin Sheath
Definition: The insulating layer around axons that speeds up the transmission of action potentials.
Example: Diseases like multiple sclerosis involve damage to the myelin sheath, slowing down nerve communication.
Glial Cells
Definition: Non-neuronal cells that support and protect neurons, including astrocytes, oligodendrocytes, and microglia.
Example: Glial cells help maintain the blood-brain barrier and repair neuronal damage.
Neuroimaging Techniques:
CT Scans
Definition: X-ray-based imaging technique used to view brain structures.
Example: Used to detect brain tumors or strokes.
PET Scans
Definition: Uses glucose tracers to observe areas of high brain activity.
Example: Shows which brain regions are active during a task.
fMRI
Definition: Measures brain activity through blood flow.
Example: Used to study brain activation while recalling a memory.
EEG
Definition: Records electrical activity from the brain.
Example: Used to study brain waves during sleep.
TMS
Definition: Non-invasive method to temporarily stimulate or inhibit brain activity.
Example: Used in research to study motor function by stimulating the motor cortex.
Chapter 3: Visual Perception
Key Terms:
Rods and Cones
Definition: Photoreceptors in the retina that detect light and color.
Example: Rods help in low-light vision, while cones detect color.
Fovea
Definition: The central part of the retina responsible for sharp vision.
Example: We use the fovea to focus on fine details when reading.
Optic Nerve
Definition: Carries visual information from the retina to the brain.
Example: Transmits electrical signals from the retina’s ganglion cells to the visual cortex.
Lateral Geniculate Nucleus (LGN)
Definition: The relay station in the thalamus for visual information.
Example: Information from the retina is processed here before reaching the occipital lobe.
Gestalt Principles of Perception
Definition: The theory that the brain organizes sensory input into wholes rather than parts.
Examples:
Similarity: We group similar items together.
Proximity: Objects near each other are perceived as a group.
Good Continuation: We tend to perceive continuous lines, even if interrupted.
Perceptual Constancy
Definition: The tendency to perceive objects as constant despite changes in sensory input.
Examples: Size constancy, Shape constancy, Brightness constancy.
Binding Problem
Definition: The challenge of integrating various aspects of a stimulus (e.g., color, shape, motion) into a coherent perception.
Example: We need to "bind" features like color and shape to perceive a full object.
Depth Perception
Binocular Cues: Use both eyes for depth perception (e.g., convergence, disparity).
Monocular Cues: Use one eye for depth (e.g., size, interposition).
Motion Parallax: Objects closer to us appear to move faster than those farther away.
Lateral geniculate nucleus (LGN)
Second for visual processing: LGN, in the thalamus, then goes to the occipital lobe
Lateral inhibition
Early processing, in ganglion cells
Neural synchrony
If neurons are firing at the same time, we think the information they give us goes with the same object.
Brightness constancy
We assume that objects have the same amount of brightness, regardless of the light that they’re in.
We increase/decrease the brightness of objects to compensate for the lighting they are in.
Unconscious inference
We know that things look smaller when they’re farther away.
We calculate the size of an object (unconsciously) based on how much space it takes up on our retina and how far away we think it is
Binocular cues
Involve comparison of what we see in each eye
Monocular distance cues
Only involves information from one eye
Motion parallax
Things that are closer to us appear more different as we move than things that are farther from us do.
Cornea
Definition: The transparent, dome-shaped surface that covers the front of the eye. It focuses light that enters the eye.
Example: The cornea helps bend light rays so they can enter the pupil and reach the retina, allowing us to see clearly.
Retina
Definition: The light-sensitive layer at the back of the eye that contains photoreceptors (rods and cones) responsible for converting light into neural signals.
Example: The retina processes visual information, sending it to the brain via the optic nerve.
Photoreceptors
Definition: Specialized cells in the retina (rods and cones) that detect light and color.
Example: Rods are responsible for vision in low-light conditions, while cones allow us to see in color and in bright light.
Acuity
Definition: The sharpness or clarity of vision, typically measured in terms of the ability to distinguish fine details.
Example: Someone with high visual acuity can read small print easily, while someone with low visual acuity might struggle to see fine details.
Bipolar Cells
Definition: Neurons in the retina that connect photoreceptors (rods and cones) to ganglion cells, transmitting visual information from the photoreceptors to the brain.
Example: Bipolar cells act as intermediaries, transmitting signals from the photoreceptors to the ganglion cells, which then send the signals to the brain.
Ganglion Cells
Definition: Neurons in the retina that receive input from bipolar cells and transmit the visual information through their axons to the brain via the optic nerve.
Example: Ganglion cells help form the optic nerve, which carries visual information to the brain for processing.
Edge Enhancement
Definition: A visual processing phenomenon where the contrast at the edges of objects is increased, making boundaries more distinct.
Example: Edge enhancement helps us perceive the shape and size of objects more clearly by making their edges stand out against the background.
Mach Band
Definition: An optical illusion in which adjacent regions of differing shades seem to exaggerate the difference in lightness at their borders.
Example: When two shades of gray are placed next to each other, the borders seem brighter or darker than the actual color, due to the Mach band effect.
Single-cell Recording
Definition: A research method that involves measuring the electrical activity of a single neuron to study how it responds to different stimuli.
Example: Researchers might use single-cell recording to study how neurons in the visual cortex respond to different shapes or colors.
Receptive Field
Definition: The specific region of the visual field that a neuron responds to. Each neuron in the visual system has its own receptive field.
Example: A neuron in the retina may have a receptive field that responds to a particular spot of light or a specific color in the visual scene.
Center-surround Cells
Definition: A type of receptive field found in the visual system where the central part of the receptive field is excited by light, while the surrounding area is inhibited.
Example: These cells help detect contrasts and edges in visual stimuli, enhancing the perception of objects' boundaries.
Area V1
Definition: The primary visual cortex, located in the occipital lobe, where visual information from the retina is first processed.
Example: In Area V1, neurons are organized to process different visual features like lines, angles, and movement.
Serial Processing
Definition: A cognitive process in which information is processed one step at a time, in a linear sequence.
Example: Serial processing occurs when we analyze one aspect of a visual scene (e.g., shape) before moving on to another (e.g., color).
What System
Definition: The brain's system for processing information about "what" an object is, typically associated with the ventral stream in the visual processing pathway.
Example: The "what system" helps us identify objects, such as recognizing a car, a face, or a tree.
Where System
Definition: The brain's system for processing information about "where" an object is located, typically associated with the dorsal stream in the visual processing pathway.
Example: The "where system" helps us understand the position and movement of objects in space, such as tracking the movement of a ball.
Conjunction Errors
Definition: Errors that occur when two features of an object (such as color and shape) are mistakenly combined during visual perception.
Example: In a visual search task, someone might incorrectly identify a red square as a green circle due to a conjunction error.
Necker Cube
Definition: A famous optical illusion where a 2D drawing of a cube can be perceived in two different orientations, demonstrating the brain's ability to interpret ambiguous visual stimuli.
Example: The Necker Cube illusion shows how the brain alternates between two possible interpretations of the same visual input.
Reversible (or Ambiguous) Figure
Definition: An image that can be interpreted in multiple ways, where different viewers might see different objects or shapes within the same visual stimulus.
Example: The classic example is the image of a vase that can also be seen as two faces, depending on how the brain interprets the visual input.
Figure/Ground Organization
Definition: The process by which the brain distinguishes an object (figure) from its background (ground) in visual perception.
Example: In a visual scene, we typically focus on the figure (e.g., a person) while the background (e.g., a park) recedes into the background.
Visual Features
Definition: Basic elements of visual stimuli, such as color, shape, size, and motion, that are processed by the visual system.
Example: Identifying a red square among a group of blue circles involves processing visual features like color and shape.
Perceptual Constancy
Definition: The ability to perceive an object as stable and unchanging despite variations in sensory input (e.g., lighting, distance).
Example: A car appears the same size whether it is close or far away, due to size constancy.
Size Constancy
Definition: The perception that an object maintains its size despite changes in the distance from which it is viewed.
Example: A car appears to remain the same size even as it moves farther away from you.
Shape Constancy
Definition: The perception that an object maintains its shape even when viewed from different angles.
Example: A door appears rectangular whether it is seen from the front or at an angle.
Distance Cues
Definition: Visual information that helps us perceive depth and judge the distance of objects in our environment.
Example: We use cues like the size of an object, shading, and motion parallax to estimate how far away an object is.
Pictorial Cues
Definition: Static visual cues in images or scenes that provide information about depth and distance.
Example: Cues like linear perspective and interposition help us perceive three-dimensional space on a flat surface.
Interposition
Definition: A depth cue where one object partially blocks another, signaling that the blocked object is farther away.
Example: If a tree blocks part of a building, we perceive the building as farther away.
Linear Perspective
Definition: A depth cue where parallel lines appear to converge as they recede into the distance.
Example: The train tracks seem to come together at a point in the distance, even though they remain parallel.
Optic Flow
Definition: The pattern of motion that occurs as we move through an environment, providing cues about direction and speed of movement.
Example: As you walk toward a door, objects around you seem to move backward relative to your viewpoint—this is optic flow.
Chapter 4: Object Recognition
McClelland and Rumelhart modification of feature net (inhibition and top-down additions)
1. Added inhibitory connections (e.g., seeing a Q not only excites a U, but it also inhibits an S).
2. Added top-down communication (two-way communication).
If a letter is seen, it makes us more likely to see words with that letter in it.
If a word is seen, it makes us more likely to see letters that are in that word.
Recognition by components (geons)
?
Feature detectors→Geon detectors→Geon assemblies→Object model
Facial recognition
Different than object recognition:
1. Viewpoint matters–our perception of faces does not work well when face is inverted
2. It is a holistic, rather than bottom-up perception
Recognition by Components (RBC) Theory
Definition: Objects are recognized by identifying basic shapes (geons).
Example: Recognizing a chair by identifying its geons: cylinders for legs, rectangular shapes for the seat.
Bottom-Up vs. Top-Down Processing
Bottom-Up: Starts with sensory input and builds perception.
Example: Identifying a shape by analyzing its edges.
Top-Down: Uses prior knowledge to interpret sensory input.
Example: Recognizing a word in a sentence even if it’s incomplete.
Prosopagnosia
Definition: The inability to recognize faces due to brain damage.
Example: Unable to recognize family members by their faces.
Inversion Effect
Definition: Faces are harder to recognize when inverted.
Example: Faces viewed upside-down are more difficult to identify.
Holistic Perception
Definition: Faces are recognized as whole units, not by individual parts.
Example: People are better at recognizing faces when viewed upright than when inverted.
Tachistoscope
Used to present people very briefly with a letter, series of letters, or word.
Used to study what makes people better able to identify letters and words.
Feature nets
Idea that there is a hierarchy of perception, from features at the bottom level to words at the top level.
Composite effect
Facial recognition relies on whole face and relationship between parts.
Visual Search Tasks
Definition: A type of cognitive task where individuals search for a target item among a set of distractors. This task helps study attention, visual processing, and the efficiency of feature detection.
Example: In a visual search task, you may be asked to find a red "X" among several blue letters.
Mask
Definition: A stimulus presented briefly after the target stimulus, designed to disrupt or prevent further processing of the target stimulus. It is often used in studies of attention or perception to limit the duration of visual exposure.
Example: In a visual search task, a mask (such as random letters) may be shown immediately after the target (e.g., a specific letter) to prevent full processing of the target.
Priming
Definition: A phenomenon where exposure to one stimulus influences the response to a subsequent stimulus. Priming occurs unconsciously and can affect perception, memory, and decision-making.
Example: If you are shown the word "doctor" and then asked to quickly identify the word "nurse," you will likely recognize it faster because of the semantic priming effect.
Repetition Priming
Definition: A specific type of priming where exposure to a stimulus (such as a word) increases the speed or accuracy with which that same stimulus is processed when encountered again.
Example: If you read the word "apple" and then later encounter the same word in a different context, your response time for recognizing the word may be faster due to repetition priming.
Word-Superiority Effect (WSE)
Definition: The phenomenon where individuals are more likely to correctly identify a letter when it appears in the context of a word compared to when it appears alone or in a nonword.
Example: It’s easier to identify the letter “R” in the word “RAT” than when presented alone, such as in a string of random letters like "QZY."
Well-Formedness
Definition: A property of a string of letters or sounds that makes it resemble a real word in the language, as opposed to a random or nonword string. Well-formedness affects cognitive processes like word recognition and reading.
Example: The string “TREND” is well-formed, while “TKNEA” is not because it doesn’t follow typical English letter patterns.
Activation Level
Definition: In cognitive models, particularly those involving feature detectors or neural networks, the activation level refers to the degree of activation or responsiveness of a particular node or neuron in response to input.
Example: When processing a word, the activation level of the node representing that word increases, making it more likely that the word will be recognized.
Response Threshold
Definition: The minimum level of activation required for a response or decision to be made. If the activation of a node or detector reaches this threshold, a cognitive response (e.g., recognition, action) is triggered.
Example: In a word recognition task, the activation threshold for recognizing a word might be lower for familiar words than for unfamiliar ones.
Bigram Detectors
Definition: In cognitive models of word recognition, bigram detectors are units that respond to pairs of letters (bigrams). These detectors help recognize familiar letter combinations (e.g., “th,” “he,” “in”).
Example: In reading, the combination "TH" is detected by a bigram detector, which aids in recognizing the word "THE."
Local Representation
Definition: A cognitive model where information is represented by a single unit or node, which holds the entire representation of the item (e.g., a word or concept).
Example: In a local representation system, the word "dog" might be represented by one unit that holds all relevant information about a dog.
Distributed Representation
Definition: A cognitive model where information is represented by the interaction of multiple units, with each unit contributing part of the information.
Example: The word "dog" might be represented by multiple interconnected units (e.g., a node for "animal," a node for "pet," a node for "four legs"), with the interaction of these nodes creating the full representation of "dog."
Excitatory Connections
Definition: In neural networks or cognitive models, excitatory connections are those that increase the activation of the receiving node or neuron. They "excite" the node and make it more likely to fire.
Example: In a neural network model of word recognition, excitatory connections might make it more likely that the concept of "dog" is activated when the input is the letter "D."
Inhibitory Connections
Definition: In neural networks or cognitive models, inhibitory connections decrease the activation of the receiving node or neuron. These connections "inhibit" the node and reduce its likelihood of firing.
Example: If a model is recognizing a word, inhibitory connections might prevent the activation of a wrong word (e.g., "cat") when the correct word ("dog") is being processed.
Geons
Definition: Geons (geometric ions) are basic, three-dimensional shapes that serve as building blocks in the recognition of objects in the Recognition by Components (RBC) model. Objects are identified by the arrangement and combination of geons.
Example: The letter "A" can be broken down into geons like a triangle and two lines. The arrangement of these geons allows for the recognition of the letter "A" in different perspectives.