Mid-term #1 Flashcards
Heritability
genetic traits must be heritable to contribute to evolution
Fitness
success at surviving and reproducing
Natural Selection
heritable features that increase the odds of reproduction will tend to accumulate in subsequent generations
CAUTION: naturalistic fallacy
how things are is how things out to be
CAUTION: deterministic fallacy
you can’t ‘escape’ your genes
CAUTION: nature-nurture binary
some trait or behavior is either because of either nature or nurture
CAUTION: teleology
evolution leads towards ‘progress’ to make the species ‘better’
Factors that Make Us ‘Us’
1) Bipedalism – walking on two limbs
2) Encephalization – the ratio of brain mass to body mass
3) Reduced sexual dimorphism – sexes more similar than other species
4) Manual dexterity – usage of tools
Intrasexual competition
Same-sex individuals compete for mates
Intersexual selection
One sex chooses mates based on attractive traits
Supernormal Stimuli
stimuli that did not exist in the environment of our species evolution
- food
- video games
-TV shows & movies
- cellphones
- internet
- pornography
Broca’s Aphasia
Difficulty producing speech, but can still move mouth muscles fine. There are no problems with understanding.
- Associated w/ damage to Broca’s area in the frontal lobe
Wernicke’s Aphasia
Difficulty understanding speech but speech production is fluent, though often nonsensical (word salad)
- Linked w/ damage in Wernicke’s area in the temporal lobe
Frontal Lobe
Action (motor cortex), cognition (executive functions), behavior, affect, and language (expressive aspects)
Parietal Lobe
Somatic sensation (primary somatosensory cortex), visuospatial perception, movement (interaction & manipulation of objects), and cognition (reading, writing, arithmetic)
Temporal Lobe
hearing (primary auditory cortex), language (speech comprehension), visual perception (object recognition and categorization), memory and emotion (hippocampus & amygdala)
Occipital Lobe
vision – primary visual cortex and visual association areas
- depth & color perception
- analysis of movement
- simple feature recognition
Descartes and Dualism
Descartes proposed dualism - the idea that the mind and body are two separate entities.
There are many problems with this assertion. It is very self-center and incompatible with known laws & facts of physics.
Social Brain Hypothesis
suggest that humans evolved larger brains to manage complex social relationships
Foraging/Diet Hypothesis
suggests that brain size increased due to the demands of finding and processing food, particularly higher-quality diets (meat, cooking, etc)
Homunculus Idea of Motor and Somatosensory Cortex
A visual representation of how different parts of the body are mapped in the motor and somatosensory cortices.
- Body parts requiring fine motor control (hands, face) have larger areas of representation
Dendrites
Soma
Axon
Myelin sheath
1) receive signals from other neurons
2) cell body; processes incoming signals and contains the nucleus
3) transmits signals away from the soma to other neurons or muscles
4) a fatty layer that insulates the axon, allowing faster transmission of electrical signals
Phineas Gage
Phineas Gage survived a severe brain injury when an iron rod went through his frontal lobe.
His personality changed dramatically, showing the role of the frontal lobe in personality and behavior.
Split-brain Patients & the Corpus Callosum
Split-brain patients have had their corpus callosum (the bridge connecting the two hemispheres) severed to treat epilepsy.
- This leads to each hemisphere processing information independently.
- The left hemisphere is responsible for language and logic, while the right hemisphere handles spatial tasks and facial recognition.
Example: If a patient sees an object in their left visual field (processed by the right hemisphere), they may be unable to name it because the right hemisphere does not control language. However, they may be able to draw or select the object with their left hand.
They cannot draw or select the object with their right hand.
Example 2: If a patient sees an object in the right visual field (processed by the left hemisphere), they can verbally describe it because the left hemisphere handles language functions.
They can also draw or select the object with their right hand but not their left.
Thalamus, Basal Ganglia, Hippocampus, and Amygdala
Cerebellum
1) relay center for sensory information going to the cortex
2) motor control & reward processing
3) long-term memory & navigation
4) emotional processing & emotional learning
5) motor coordination
Techniques in Neuroscience:
Neuroimaging, Electroencephalogram (EEG)
Single Unit Electrophysiology
Lesions & Perturbations
1) fMRI (measuring brain activity by detecting changes in blood flow)
PET (tracks a radioactive tracer to observe metabolic processes)
2) records the brain’s electrical activity through electrodes placed on the scalp
3) measures the electrical activity of a single neuron using a fine electrode inserted to or inside the neuron
4) lesions involve studying the effects of brain damage or injury
perturbations involve techniques like TMS that temporarily disrupt or exchange activity in specific brain areas to study their role in cognition, sensation, or movement
5 Sensors of the 5 Senses
Vision - photoreceptors in the eyes
Hearing - hair cells in the cochlea
Taste - taste buds on the tongue
Smell - mucous neurons in mucous membrane
Touch - mechanosensitive sensory neurons in the skin
Physical stimuli sensed by each sense
Vision - light waves
Hearing - sound waves
Taste - dissolved molecules in saliva
Smell - dissolved molecules in the area
Touch - physical pressure, temperature
Photoreceptors
1)
2)
1) Rods - vision at low light levels
2) Cones - color vision & high-resolution vision
Hubel & Weisel experiment & implications
1980s - used electrodes to record activity from individual neurons in the visual cortex of cats.
They found that specific neurons respond to particular features of visual stimuli (edges, angles.)
–> Research showed how the brain processes visual information and supported the idea of feature detectors (neurons have preferences for certain features in the world).
1) Ventral Stream
2) Dorsal Stream
1) vision-for-perception
2) vision-for-action
Sensory adaptation
According to opponent processing, colors can ‘compete’
When one type of color-sensitive neuron gets ‘tired’ (via neural adaption) the opposing color response is stronger in our perception.
This does not apply just to colors. Neurons receptive to all kinds of sensations can get ‘tired’.
Example: Locke’s hot, cold, and lukewarm water buckets. The hand in hot water felt hot and the hand in cold water felt cold when placed in the lukewarm bucket.
Gestalt Principles
1) Closure
2) Similarity
3) Continuity
4) Proximity
Based on perception & organization. Our minds perceive things as part of a whole and we have predisposed ways of organizing information.
Closure: seeing an image with missing parts and filling them in to complete the image in your head
Similarity: objects that are similar to one another are grouped together
Continuity: people perceive continuously flowing and smooth lines even with interruption
Proximity: objects close to one another are grouped together
Stimulus cues
1) occlusion
2) crispness
3) motion parallax
4) perspective
- think of a painting-
Occlusion: Things in the foreground block things in the background
Crispness: The more definition, the closer it is. The less definition, the farther it is.
Motion parallax: Stimuli with different relative motion when the observer is moving will be perceived to be at different distances
Perspective: Background and vanishing lines can provide clues about the relative size of objects
“Wolfpack effect”
orientations of a group of moving shapes automatically yields a perception of animacy when the shapes continually point towards a single target shape, even if their actual motions were random.
Expectations shape perception, even across the senses.
1) Auditory expectancy
2) McGurk Effect
Auditory expectancy – the brain fills in gaps in unclear auditory input based on prior knowledge.
McGurk effect – visual information can alter what we hear, showing how our brain integrates multiple senses.
Neglect
failure to attend to one side of space, often due to right parietal lobe damage.
Anosognosia
lack of conscious awareness of one’s neurological condition.
Blindsight
unconscious visual processing in blind areas of the visual field, linked to damage in the primary visual cortex.
Bottom-up versus top-down attention
Bottom-up Attention: sensory-driven process that directs attention to stimuli that are considered salient or attention-grabbing
Think POP OUT (Loud noise or something moving quickly) → automatic
Top-Down Attention: moving spotlight(s) of attention
Think VISUAL SEARCH (Where’s Waldo) → conscious
Attentional capacity
attention is limited, you can usually only seriously attend to about one thing at a time.
Cocktail party effect
the ability to focus one’s auditory attention on a single sound source amidst background noise
Freud and the unconscious (id, ego, superego)
We are not always aware of our motivations.
The Unconcious drives much of our own behavior.
Id - instinctual drive present at birth: does not distinguish between reality and fantasy; operates according to the pleasure principle
Ego - develops out of the Id during infancy; understanding reality and logic, mediator between Id and Superego.
Conscious:
Superego - internalization of society’s moral standards; responsible for feelings like ‘guilt’
Top of the iceberg.
Unconscious priming
exposure to a stimulus unconsciously influences your response to a later stimulus.
Cognitive control and the “Stroop” effect
Cognitive control – conscious inhibition of automatic responses.
The brain’s ability to regulate attention, thoughts, and actions based on goals.
‘Stroop Effect’: The conflict between automatic processes and cognitive control.
Example: Saying ‘blue’ when the word ‘red’ is printed in blue ink.
Habituation
a decrease in strength or occurrence of behavior after repeated exposure to the stimulus that produces the behavior
Campus squirrels are habituated to humans.
Ironic Rebound
a psychological phenomenon that describes how trying to suppress a thought can make it more likely to occur
Sensitization
the presentation of a harmful stimulus can sometimes cause an animal to mount a defensive response to a subsequent harmless stimulus. As a result, defensive reflexes for withdrawal and escape become heightened.
Individuals with PTSD show enhanced sensitization responses to non-threatening loud noises.
Pavlovian Conditioning (UCS, UCR, CS, CR)
Learning by associating a neutral stimulus with a meaningful stimulus.
UCS - unconditioned stimulus, which is a stimulus that elicits a reflexive response
UR - unconditioned response, which is the natural response to an unconditioned stimulus
NS - neutral stimulus, which is a stimulus that does not initially elicit a response
CS - conditioned stimulus, which is a stimulus that elicits a response after being paired with an unconditioned stimulus
CR - conditioned response, which is a response that is elicited by the conditioned stimulus
Extinction & Exposure Therapy
Extinction: unlearning of a previously learned association
Exposure therapy: repeatedly exposing a person to stimulus in a safe setting = reduced phobia
Not perfect though…
Context Reinstatement
conditioned response is recovered after exposure to an unconditioned stimulus.
Associative Bias (aka Garcia Effect)
we are predisposed to get conditioned by some stimuli (e.g., snakes and guns) more easily than neutral stimuli.
Generalization
if we learn that a certain stimulus leads to particular outcomes, stimuli with similar features may produce conditioned responses.
Example: A painful bite from one bug may lead to a fear of other bugs.
Blocking
prior conditioning with one stimulus prevents the conditioning of a new stimulus.
Example: A dog conditioned to respond to a bell does not learn to respond to a light presented with a bell.
Operant conditioning
Learning based on consequences (rewards or punishments)
Main dichotomies of operant conditioning
Reinforcement vs. Punishment
Reinforcement: increases behavior
Punishment: decreases behavior
Positive vs. Negative
Positive reinforcement: adding a pleasant stimulus
Negative reinforcement: removing an unpleasant stimulus
Positive punishment: adding an unpleasant stimulus
Negative punishment: removing a pleasant stimulus
Behaviorist Philosophy
Emphasizes observable behavior over internal mental states.
Focuses on learning through conditioning.
Believes behavior is shaped by the environment
Generally adopts a deterministic view on behavior.
Sensory Memory
- short-lasting, high-capacity ‘imprint’ in a sensory system (hearing, vision, etc) that lasts about a second or less.
Short-Term Memory and Chunking
STM - active, conscious memory for recent events/stimuli
Chunking information allows you to remember more.
Think of remembering a phone number!
Persistent brain activity in short-term memory tasks
The prefrontal cortex maintains information and refreshes it over seconds/minutes.
Semantic vs. Episodic LTM
Episodic LTM: specific autobiographical events, with spatial and temporal context.
Ex: Memories at your high school graduation.
Semantic LTM: facts or knowledge about the world, including ‘general’ personal information.
Ex: The year of your high school graduation.
Semantic memory as distributed neural representations
Semantic memory is represented across a network of neurons.
- Neural networks involve multiple brain areas.
- Different features of concepts are processed in distinct regions.
- Concepts are formed through associations and connections.
- Neural plasticity allows for the updating and organization of semantic memory.
3 Key Points on Memory Encoding
1)
2)
3)
& Flashbulb Memories & The Method of Ioci
1)Attention matters.
2)Emotion matters.
- Emotion can strengthen memory encoding.
- Trauma and ‘flashbulb’ memories – people reported that their memories of traumatic events (9/11, the Challenger Explosion, etc) were surprisingly vivid and recalled them with high confidence.
However, people may be overconfident about these memories and get many details wrong.
3) Mental imagery helps.
- Bizarre/novel mental imagery is effective for memory.
The Method of Ioci (the ‘memory palace’)
2 Key Points on Memory Retrieval (and cues)
1) The original encoding context matters for retrieval
2) Cues are everything!
Free Recall: Describe your high school gymnasium
Cued Recall: Here’s a photo of the entrance to your high school gymnasium. What does it look like inside?
Recognition: Is picture A or B your high school gymnasium?
False recognition experiment with word lists
DRM paradigm - People falsely recognize items they have never seen, especially when those items are semantically related to things they did see.
Source misattribution – misremembering the source of a memory
Retrieving a memory can change it - the encoded location moved when recalled.
Implies that episodic memory is constructive.
“Lost in the Mall” study
Loftus & Pickerel, 1995 – participants were presented with 3 true events from their childhood and 1 fabricated memory (getting lost in the mall)
The stories were presented by an older relative, who was secretly working with the experimenters.
25% of the participants reported remembering FALSE memories of getting lost in the mall.
Some even stated they vividly remembered it happening.
Car Crash video Loftus & Palmer study
All participants watched the same video of a car accident, were grouped, and given a different questionnaire.
“About how fast were the cars going when they (smashed/collided/bumped/hit/contacted each other)
When asked how fast the cars were going when they smashed/collided, they recalled higher speeds.
This even applied when asked whether or not people saw broken glass (even though there was no broken glass).
Those who were asked w/ the word ‘smashed’ more often reported seeing broken glass.
HM experiments and findings, and implications for different components of long-term memory
HM - underwent hippocampus & surrounding medial temporal lobe removal to treat epilepsy, resulting in profound amnesia.
H.M. could not form new explicit memories but could learn new skills (implicit memory)
- Cannot learn new words/concepts after surgery.
- He can remember and recognize celebrities pre-surgery but not after.
-He can only remember 6 digits after studying a list.
HOWEVER, he can learn a new motor skill, even though he doesn’t consciously remember ever performing it.
Implications:
Explicit memory: reliant on the hippocampus
Implicit memory: involves different brain areas, including procedural memory.
Multiple memory systems: different types of memory have distinct neural mechanisms
Memory consolidation and retrieval: emphasizes the importance of the hippocampus in consolidation and the role of other regions in long-term storage.
Theories of infantile amnesia
Hippocampal neurogenesis - the process of generating new neurons in the hippocampus.
New neurons disrupt existing memories, leading to memory loss.
Neurological development - immature hippocampus hinders memory formation
Language development - lack of language skills affects memory encoding and retrieval
Freud: repression - we repress childhood memories.
