Lecture Notes - Adrianna Jenkins PDF

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Guest Lecture: Appetite ❖ Biology and Food intake ➢ Evolution primacy ➢ Developed & Developing world ➢ Time occupied ➢ Expense (10% on food approx.) ➢ Motivation to eat when in energy deficit: HUNGER ➢ Regulation of food intake (even though you don’t count calories) ❖ What causes people to eat? ➢ Hunger ➢ Availability ➢ Memory for how much you eat; recent eating episodes ❖ Negative feedback homeostasis ➢ FOOD INTAKE -> (+) Energy status) -> (-) Energy status -> FOOD INTAKE ➢ Food intake -> Oral -> gastrointestinal -> Blood, liver, etc -> Brain hypothalamus ❖ Food choice: innate predispositions ➢ Omnivore: advantages and disadvantages ➢ Great adv.: 3 great omnivores (humans, rats, cockroaches ➢ Balanced neophobia and neohilia ➢ Special adapted long-delay learning ➢ Taste preferences ■ Sweet positive, bitter negative, ■ Sugar: biology drives culture ● Innate sweet preference ● Search for sweet foods (fruits) ● Cultivate sweet foods ◆ Colonization of Americas ● Extract sugar ● Develop non-caloric sugar substitutes ● Ex. Chocolate: biology drives cultural innovations to make super food ◆ Chocolate bean: bitter and not particularly aromatic ◆ Elaborate cultural technology/processing ➢ Add sugar and sometimes milk ➢ Process beans to enhance aroma ➢ Various processes to bring out smoothness of chocolate butter (fat) ◆ Creation of a sugar-fat-aromatic super food ➢ Melts in mouth, most craved food in america ❖ Preadaptation of the mouth ➢ Nutrition -> pleasure -> social marker, bonding, interacting & art form & moral entity ❖ Food is distinct among the biological systems ➢ Culturally enhanced ➢ Late 20th century developed world

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■ Epidemiological revolution: longer life, less death from degenerative diseases ■ Food surplus ■ Extraordinary range of food choices ■ Development of superfoods (ex. chocolate) ■ No work needed to attain choices ➢ Old mind in a new world ■ If it is edible, eat it: bias to eat ■ Magical thinking: the law of similarity ● Appearance = reality Obesity epidemic ➢ Avg weight gain per year by US adults: 1-2 lbs ➢ Health costs vs. obesity ➢ Cosmetic & self esteem problems ➢ France vs. usa Factors in food attitudes ➢ Consumption of a fat-reduced food ➢ Worry or concern about food ➢ Portion size ■ Smaller supermarket food portions ■ Incremental changes ● One apple less a day: loss of 8 pounds Unit bias ➢ Eating one thing (with Andrew Geier) Biology, psychology, and culture ➢ Biology: regulation system, sweet and fat preferences ➢ Psychology: experiences and learning about consequences of foods ➢ Culture: appearance norms, ideas about proper foods, proper times to eat, and proper amounts Eating ➢ Context of eating ➢ Consumption ➢ Preference ➢ Liking Determinants of liking ➢ Mere exposure ➢ Evaluating conditioning taste-aversion learning ➢ “Social influence” ➢ The family paradox ➢ Chili pepper: biology opposed by culture ■ Innate aversion to irritant tastes ■ Exposure to chili pepper somehow produces liking ■ Cultivation of chili pepper, varying irritant properties ■ Incorporation into cuisine as a flavor principle ■ Benign masochism ● Favorite level of chilli is just below rejected as too strong

● Irritant spices; ginger, black pepper, coffee ● Very hot or cold foods ● Thrill rides: roller coaster ● Sad events: movies, plays, paintings, music ❖ The 21st century New Omnivore’s Dilemma ➢ Concern about long term health ➢ Concern about animal mistreatment and killing ➢ Concern about the Earth: sustainability ❖ Solution: insects!

Mind contains residues of our experiences

Education Types of learning ➢ Nonassociative - Learning about a stimulus, such as sight or sound, in the external world - Habituation - Sensitization - (stimulus over time) ➢ Observational - Learning by watching how others behave ➢ Associative (intuitive) - Learning the relationship between two pieces of information - Classical conditioning - When we learn that a stimulus predicts another stimulus - Ex. green skies and tornadoes - Operant conditioning - When we learn that a behavior leads to a response ➢ Classical (pavlovian) conditioning

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When a neutral item becomes associated with a stimulus that already elicits a response, the neutral comes to elicit the response - Experiment - Food stimulates response (drooling) - Unconditioned stimulus - Stimulus that elicits a response, such as a reflex, without prior learning - unconditioned response - Used a metronome (neutral stimulus) - Conditioned stimulus, conditioned response - Are not intrinsic properties of stimuli and responses themselves - Ex. reading comments -> higher self-consciousness - Unconditioned stimulus - Symbol of commentation can become a conditioned stimulus - Sound of comment notification “ ➢ Extinguishing associations - Animals need to learn when associations are no longer valid - Extinction: when the conditioned stimulus is repeated without the outcome, it is less powerful - “Ability to unlearn” - Recovery - Extinguished response - The dog still salivated - Association is actually inhibited, not broken. - Prediction error - difference b/t that is expected and what actually happens. - Pos. prediction error strengthens an association - Neg. prediction error weakens an association - REscorla-wagner model - Cognitive model of classical conditioning - It holds that the strength of the CS-US association is determined by the extent to which the unconditioned stimulus is unexpected - Role of dopamine - Role in learning associations -

Memory ❖ ❖ Multiple memory systems

➢ Sensory input ➢ Sensory buffer (iconic & echoic memory) ■ Span of apprehension ● How many items can you apprehend from a single, brief presentation? ● Seems to be limited to about 4,5 items (using full-report procedure) ● Partial report procedure (sound added) ◆ Report different rows based on sound (high, middle, low) ◆ Perform better ◆ Suggests bottleneck in sensory buffer -> short-term memory raft ➢ “Only 4 would reach raft before the ship sank” aka. Forgotten ■ Contains momentary sensory information ■ Transfers information to short-term memory serially (1 item at a time) ■ What gets transferred first is not just random ■ Rapid loss via fading over time ➢ Short term memory (held in a verbal code) ■ Maintained via rehearsal ■ Loss via forgetting ■ The amount of info that can be held in working memory ■ Limited capacity (4-7 items) ■ Maintained through rehearsal ➢ Long term memory ■ Procedural - riding a bike ■ Declarative - things you know ● Semantic - gen. Knowledge ■ Limited capacity ■ Possibly retained for life ■ Failures more often due to retrieval than storage ❖ Primary effect ➢ People have a good memory for items at the beginning of a list ■ Reflects long-term memory ❖ Recency effect ➢ Ppl also have a good memory for items at the end of a list ■ Reflects working memory ❖ Chunking ➢ Bundling items of information together into meaningful units ➢ More efficiently you pack items into memory storage, the more you can carry with you

➢ Increases ➢ Depth of processing -> long term memory ■ Shallow processing ● Structural encoding: emphasizes the physical structure of the stimulus ◆ Is the word written in capital letters? ■ Immediate processing ● Phonemic encoding: emphasizes what a word sounds like ◆ Does the word rhyme with weight? ■ Deep processing ● Semantic encoding: emphasizes the meaning of verbal input ➢ Exposure does not guarantee encoding ■ Cannot fully recall penny ■ Not all info processed by the sensory system gets encoded into short term memory ■ Info that we attend to in the sensory buffer passes into short-term memory ■ Only then can it have a change of passing into long-term memory ■ An item's characteristics and associates are linked to it ■ The closer the nodes, the stronger the association will be ■ Activating ❖ Amnesia ➢ Retrograde amnesia ■ Losing preserved memories prior to brain injury ➢ Anterograde amnesia ■ No info encountered after brain energy is kept ■ X new information kept ➢ Global amnesia ■ Both memories before and after injury are lost ■ Basically living w/o memory ❖ What happens when no info can get from short-term to long-term memory? ➢ Ex. Clyde Werring ❖ Multiple memory systems ➢ Sensory buffer holds sensory info brioeft;y ➢ Short term working memory has a storage limit and is maintained via rehearsal ■ Chunking can help get around the storage limit ➢ Long term memory is more limited by retrieval ability than storage capacity ■ Increasing attention and depth of processing at encoding make retrieval more likely ➢ Memory is distributed in the brain ■ The hippocampus is critical for creating new memories but not critical for

remembering old ones.

Memory Cont. ❖ Long term memory gone right, long term memory gone weird ❖ Long term memory ➢ Explicit memory “declarative”: Requires conscious effort and often can be verbally described ■ Episodic: personally experienced events, 1st person ● Ex. how easy was it for you to get out of bed this morning? ● Ex. What did you do on your 18th birthday? ■ Semantic: facts and knowledge (Jeopardy) ● Ex. how many feet does an elephant have? ● Ex. What river runs through Budapest? ● Ex. Where were you born? (personal info can also be semantic) ■ Parts of episodic memory can become semantic memory but semantic memory doesn’t turn into episodic memory ● Ex. memories of birthday -> list of 3 activities ➢ Implicit memory “nondeclarative” ■ Doesn’t require effort and often cannot be verbally described ● Conditioning: associating two stimuli elicits a response ● Procedural: motor skills and habits ❖ Encoding ➢ Last time: depth of processing, chunking ➢ Context-Dependent Memory ■ “Compatibility principle”: situation at encoding contains cues that help retrieval ■ Ex. words studied and tested in the same environment were more likely to be recalled ➢ State-dependent Memory ■ Like context-dependent memory, but the context is your internal state (anxious, hungry, gleeful) ➢ Retrieval cue ■ Any stimulus (even a thought) that leads you to remember something ■ Why are odors such effective retrieval cues? ● Anatomy: olfactory bulb to hippocampus to amygdala ● Evolution: prepared learning: strong olfactory associations ● Dilution: smells are more difficult to rehearse, thus stay stuck in time ❖ Memory gone wild ➢ Injury, surgery, disease

➢ Everyday “sins” of memory: 7 sins of memory ■ Forgetting ● Transience ● Absent-mindness ■ Distortion ● Bias ◆ People tend to recall their past beliefs and past attitudes as being consistent with their current ones ➢ Memory bias ◆ Ex. how much should student have a say in university policies? (not at all/ a lot) Write an essay for selected position. ➢ Students shifted in the direction whichever side they were assigned to write for. ➢ Memory shifted to their own beliefs ➢ People tend to recall their past beliefs to be current their ones ● Suggestibility ◆ The thendnecyf for people to develop biased memories from misleading information ◆ Ex. participants watch drivers’ ed film of a fender-bender ➢ How fast were the cars going when they ____ into each other? ■ Words (bump, crash, smash etc) ■ Had systematically different memories ➢ Wait a week. Asked: did you see any broken glass? ■ Participants asked questions using harsher verbs had memories that they have seen broken glass. ● Misattribution ◆ False memory ◆ Elements of experience remembered yet misattributed memories ◆ Eyewitness testimony ➢ Only information that gets prioritized makes it into long term memory ➢ But it’s often not clear what information is important until later ◆ Can arise in normal, daily life ◆ Cryptomnesia ➢ When a person thinks they have come up with a

new idea, ut reality just retrieved a stored idea and failed to attribute ideas to true source ■ Persistence ■ Flashbulb memories ● Kennedy assiassination ● 9/11: SEPT 12, 2001, students were asked about what happened ◆ Flashbulb memories are no more accurate than normal memories ◆ Memory for an intense event is not generally more accurate than other memories but people believe they are more vivid ◆ Memory becomes volatile when they are retrieved & has to be restored; retrieving a memory changes the memory ➢ Common-sense view ■ Encoding -> storage -> retrieval -> ➢ Reconsolidation ◆ Long-term memory is a lot like a bed sheet; after you unpack it, you can never put it back into the package the same way again. ● Boston marathon bombing ■ Sins of memory may be a tradeoff; ● Mental time travel: memory for the past makes it possible to think about the future ◆ Associations -> predictions ◆ The imprecision of memory allows us to make predictions about future situations that are similar, but not identical to situations encountered in the past. ➢ Case study: HM (1926-2008) ■ Severe epilepsy, but otherwise normal ■ Stopped making new memories in 1953 (age 27) ■ 1953: surgery to remove the hippocampus (surrounding tissue and part of amygdala) in an effort to stop seizures. ■ No new explicit memories (asked about words made after 1953) ● Software? “Expensive clothing made of soft, twilled fabric” ● Granola? “A portable keyboard wind instrument” ■ HM could make implicit memories ● skill, procedural memory ● Tracing shapes; showed development of skill ● Even though explicit & declarative memories were unable to be formed, new implicit memories could be formed ■ Conditioning ■ Suggests importance of hippocampus in long term memory

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● The hippocampus might be essential for transfer from STM to LTM, but it might not be essential for retrieval from LTM Sensory input -> sensory buffer -> short term memory -> (HIPPOCAMPUS NEEDED) -> long-term memory Korsakoff’s Syndrome ■ Anterograde + retrograde amnesia ■ Filling in memory gaps based on environmental cues ● “Confabulation” Amnesia: what we’ve learned ■ Explicit (declarative) memory: impaired in amnesia ■ Implicit memory: spared in amnesia Long term memory ■ There are multiple types of long term memory ■ The hippocampus plays an important role in acquiring long-term memory; over time, memory becomes distributed in the brain ■ Long term memory retrieval depends on context ■ Long term memory is constructive and malleable ■ “We most consider what person stands for...which, I think, is a thinking intelligent Being, that has reason and reflection, and can consider itself as itself, the same thinking thing in different times and places” - John Locke ● Memory and continuity is important our experience as a self

Consciousness ❖ Own memory provides basis for imagination ➢ Range of our imagination is bound by our experiences ❖ Consciousness ➢ Thought experiment: “P-zombies” ■ Philosophical zombie: someone who looks and acts in every way like a typical human but lacks conscious experience ■ Capacities of different entities ■ Ex. ● Which is more capable of hunger, planning ahead, feel joy, etc. ■ We treat other entities according to ur perceptions of their consciousness ■ Agency vs. Experience ● Babies: High capacity for experience ◆ Protect from harm ● Adult male: high capacity for agency ◆ Hold responsible for actions ➢ Continuity of consciousness as the basis for responsibility

■ “If the same Socrates waking and sleeping do not partake of the same consciousness, Socrates waking and sleeping is not the same person . ❖ “Easy” problem ➢ What are the neural correlates of consciousness? ➢ What is different between sleep and wakefulness? ➢ Coma ■ A prolonged states of unconsciousness ● Unresponsive to the environment ● Some patient’s brains react from stimulus ◆ Ex. standard to deviant tone played to patient ➢ Patients more likely to wake up from coma are patient that have different EEG maps during standard and deviant sounds ◆ Ex. coma patient ➢ Tennis imagery vs spatial navigation imagery ➢ Activity in patient’s brain and healthy volunteer’s brain were similarly activated ➢ The global workplace model ■ No single area of the brain is responsible for general awareness, or consciousness ■ At any one tie, each person can be conscious of a limited number of things ■ There is a tight link b/t attention and conscious awareness ● Selective attention ● Attentional blink ■ Case of hemi-neglect ● A lack of attention to one side of the perceptual field ● Right parietal hem-neglect: lack of attention to the left part of the world (ex. Contralateral neglect) ● Caused by damage to the right parietal lobe ● Radar for left hand side is not working ● Unable to bisect lines ● If hemi-neglect is rally a lack of attention to a particular part of aspace, it should be a multisensory phenomenoN ● Interim summary ➢ Conscious awareness has a limited capability ➢ Attention gates conscious awareness ➢ We can miss even “big” stimuli in our environment if we're not attending to them ➢ Automatic ■ Fast, unconscious, everyday decisions

➢ Effortful ■ Slow, conscious, ➢ Myth of multitasking ■ Confusing the use of two different sense, or two different body parts, with attending to multiple things ■ There is only one “attention” ● And it has a limited capacity ➢ Stroop task (reading colors with different color words) ■ Word reading is automatic ■ Color naming is effortful ■ The automatic process and the effortful process produce different answers. The automatic process is faster and, in this case, wrong. ❖ Heuristics in decision-making ➢ Shortcuts that reduce the amount of thinking that is needed to make decisions ➢ Availability Heuristic ■ Making a judgement based on how easily information comes to ind ● Ex. is r more commonly the first letter in a word or the third letter? ◆ R__? Or __R__? ◆ Brain thinks more words start with R because it is easier to think of ■ After a plane crash is reported in the news, more people take the train ■ Days with unseasonably cool weather can lead people to deny climate change. ➢ Representativeness Heuristic ■ Evaluating the likelihood of something belonging to a particular category based on how well its ■ Ex. ● medical diagnoses ● Legal proceedings ● Everyday stereotyping ● “If it looks like a duck and it quacks like a duck, it is probably...a duck” ■ The way we think about ourselves fundamentally different than the way we think about other people and things ● In reasoning ● In memory ● In brain activity ● Better than average “lake woebegon” effect ◆ Where all the women are strong, all the men are good looking…” ◆ Ex. compared to the average person, how good a driver are

you? ◆ Most reported they were above average. ■ The self=good heuristic ● Information about ourselves are generally positive ● Information ◆ Self dependable ◆ Other polite ◆ Self daring ◆ Other curious ● The way we think about ourselves is fundamentally different than the way we think about other people and things in reasoning, memory, and brain activity...