370: Auditory Grouping

ILD & ITD

These are not effective for judgements on elevation since in many locations they may be zero.

JUDGING ELEVATION & DIRECTION

Hoffman had people come into the lab and try to judge where sound was coming from.  They are pretty good judges before anything happens to them.  Then they change the shape of the pina so they no longer have spectral cues.  So they can still tell left to right but they have no idea what height the sound is coming from.  However, after having this thing in your ear for 19 days you find that people start to acclimate and they can now tell where sound is coming from.  So what if you take it out?  People would basically just go right back to where they were.  So basically the shape of your ear helps you determine where sound is coming from (up or down).

Owls have feathers that grow in the same direction on both sides of their head.  This makes it so they can hunt in complete darkness.  They are a really good model if you want to study hearing ability.

The superior olivary nucleus (not sure what this word actually is) has these same type of coincidence detector neurons.  The idea is that if you have sound coming from both ears if they hit the olivary at the same time then they know something is coming from straight above, below, in front, or behind the person.

So you have coincidence detectors that only fire if they have two inputs at the same time.  If a detector takes longer to get stimulated then the side that took longer to reach the detector is the direction the sound is coming from.  Also there are different rows of coincidence detectors for different frequencies of sound.  So how do you figure out which frequency is which?  For example, if two people are singing the same not but on different sides of you (same frequency) how can you tell which is which?  Basically you can tell the difference between the timbres but we do not know how our brain is able to do this.

AUDITORY GROUPING

We can group things based on what frequencies are coming from a similar location.  Single sound sources tend to come from one location.  A single sound source tends to move continuously which is  called smooth motion (e.g., doplar effect).  Similarity is the idea that similar frequencies tend to produce sounds of the same timbre.  So the things that are closer together get grouped together.  Stream segregation is something that, when sped up, you hear sounds start to segregate into multiple melodies.  So if a low and high not alternate slowly they seem to jump back and forth between each other but if it is sped up then the high and low notes seem to be two separate melodies.  This is similar to the idea behind gestalt principles.  If the frequencies are close together it is harder to segregate notes.

EXAMPLES OF SOUND EFFECTS

There are cumulative effects of repetition on streaming, meaning that if something is played together for a short amount of time it won't segregate but if you play it for longer periods of time it can start to segregate over time.  Melodies can pop out.  We also segregate high notes from low notes.  Grouping in timbre seems to overcome grouping high and low notes in the crossing trajectory example.  There is also a "common fate"thing going on when common frequencies change.  Adding vibrato to a chord causes it to sound like a voice.  There is a type of auditory occlusion if a sound is played between a sound where if it was silence instead of a sound is seems that the sound cuts off instead.  A similar effect to this is the picket fence effect with speech.

375: Reading

FROM WORDS TO SOUNDS

Which comes first, the sound or the meaning? Or is it possible that you access both at once?  Turns out that we can dissociate between these two things.  There are three sort of possibilities.  ONE is a lexical lookup (irregular).  For this you have to use meaning first because it doesn't sound like it looks like.  TELF is a direct construction (pseudowords).  WON is a combination of lexical lookup and direct construction (irregular).

The brain has separate processes for this.  There is something called acquired dyslexia, which is acquired later on in life.  Surface dyslexics are impaired on the lexical route.  This means that you will be impaired at irregular words, fine with non words, and ok at regular words.  Deep or phonemic dyslexics are impaired at the contraction route.  This means you can pronounce both regular and irregular words but you cannot pronounce non-words or pseudo words.

Regular, then irregular, then lastly pseudo words are listed in order of which route is quickest to use to pronounce a word.  Lexical always win which is why you don't mess up when pronouncing words like ONE.  However when construction and lexical are close in a word then there is delay before you are able to pronounce the word.  We don't necessarily have to use the meaning to get the sound but this is the usual route.

USE SOUNDS TO ACESS MEANING

Van Order had people decide if words were real words or not, and then if the word is the member of a category or not (e.g., is meat part of the food category?  How about rock?)  Meat would be endorsed in this category of food 100% of the time.  Meet is endorsed about 25% of the time.  Melt is endorsed 10% of the time.  Rock is endorsed 0% of the time.  In meet and melt people will sometimes initially use the sound to get the meaning but then they will realize their mistake.  This shows that sometimes sound is used before meaning.

READING: EYE MOVEMENT

When you read what do your eyes do?  They will fixate and saccade.  Fixation will last for about 200-250 ms then it will jump between fixations (lasts about 25-50 ms & jumps 7-9 characters) and this jump is known as a saccade.  You do not actually process any information in this jumps.  So the question is how much info can you extract with each fixation?

The fixation point is about the size of a quarter held at arms length.  That is not very big so are we only able to see detail in this point or can we see details from the whole scene or page?

Eye Tracking
How do we see these saccades?  People have volunteered to let researchers put a camera close to their eye and track the movements.  They found that a person who is reading has smaller times for fixation than people doing a visual search. The visual searchers also move backwards sometimes.  Visual search in dyslexics is pretty similar to normal but in reading by someone with dyslexia it was very jerky and random seeming.

Moving-window Technique
If you mask out the letters that are outside the fixation point then it was found that people didn't notice.  So the words in the fixation point were normal (about 15 characters long) and there were random jumbles of letters outside of the fixation point.  They also did this with X's instead of random letters but that was a bit more noticeable.  The reason we don't notice is that we are not attending to that information.  It was also found that we read about 2 words at a time (normal reading rate is 330 wpm, 1 word takes us to 200 wpm, 2 words is 300 wpm, & 3 words is 330 wpm).  Good readers process the currently read word plus the next word at the same time.

Perceptual span is where you are fixating plus a little bit to your right (or left if you read right to left).  You can switch fluently between these two (left or right) if you start reading in a different direction.  What if you could increase the perceptual span?

INCREASING THE PERCEPTUAL SPAN

Just & Carpenter took these speed reading classes and measured their saccades to see if the speed reading classes really did what they claimed to do.  They found that reading speed increased but comprehension did not improve.

CONTEXT ON WORD IDENTIFICATION

Do you read faster if you know what is coming up next?  Yes.  So for example if you see a sentence with a baker taking a bomb to a wedding or a baker taking a cake to a wedding you will process the second sentence faster because it is normal but the surprising bomb would cause you to process the information slightly slower.

382: Exam II Review

1. Lecture 10 Stress Management
1. Successful Aging
1. Successful Aging
2. Harvard Study
1. some people are more extroverted
2. high social status and prestige is related to longevity
3. happily married = longevity
4. No smoking or alcohol
2. Stress Management
1. lifestyle
1. best exercise is to do one that you enjoy/like
2. Psychosocial factors
1. Religiosity and Meditation
1. These do not work for everyone.  You have to enjoy it.
2. People that don't like to meditate don't get help from it.
3. Methods
1. Learning to Breathe at your resonant rate (5 or 6 breaths/minute)
2. Visualization
3. Imagery
4. Progressive Muscle relaxation
5. Body scan
6. Autogenics: my body is warm and heavy (associated with parasympathetic system)
7. Sleep heigene: consistent sleep time, don't exercise right before bed time, no TV in your room, cool temperature of the room, comfortable quiet dark environment, only sleep on your bed
3. Breathing
1. Braking: learning to breathe deeply
1. If you do four hours of training you usually have developed the habit well enough to do it on your own
2. Breathing
3. Awareness
2. Lecture 12: Stress and Your Heart
1. Stress and Health
1. Stress and Death
1. 5 steps of stress response
1. get energy now
2. move energy
3. stop long term projects
4. blunt pain
5. increase cognitive function
2. Allostasis
2. Hypertension
1. Defined
1. 115/75
2. 140/90 is hypertension
3. Pre hypertension is
2. Mechanisms
3. Heart Health
1. LVH
1. Left Ventricular Hypertrophy
1. Your heart beats harder and develops the muscles more but the bulky muscles causes less flexible heart
2. Hypertension is really the result of a high stress lifestyle
3. Ischemia
1. lack of oxygen to the heart pump/muscle
2. even though all the blood goes through the heart the heart is not fed by that blood.  It is fed by it's own arteries on the outside of the heart that feed the heart and those are what get blocked.
4. SNS/PNS balance
1. SNS can contribute to heart disease but we need it for energy.  The biggest thing is that we need to have balance between SNS and PNS
3. Lesson 13: Stress and EAting
1. Food Principles
1. Eating Guides
1. myplate.gove
2. Eating Principles
1. all fat is not bad.  Emphasize omega 3 and poly & mono unsat fats
2. 
   
3. The future
2. Eating and Disease
1. Disease
1. heart disease and diabetes type II
2. 2 years ago in texas was first type II diabetes case in a 12 year old
2. Metabolism
1. affected by stress and what you eat
3. Stress and Appetite
1. Cortisol
1. after you have been through a stressor cortisol will increase your appetite
2. Evolutionarily stress implies a use of energy but in our society now stress does not always involve using energy but we still get the craving
2. Craving
1. We crave sugar and fat
4. Lecture 14:Stress Management - lifestyle
1. Time management and personal Values
1. Covey Big Rocks example
2. Priorities
1. it is important to start with time management
2. Exercise and Diet
1. Exercise
1. if you do an exercise you don't enjoy your amygdala will activate fear and threat making it hard to continue
2. Diet
1. eat a balanced diet
3. Sleep/Your Goals
1. Sleep
1. sleep principles
2. increase sleep quality will decrease your cortisol and stress levels
2. Your Goals
5. Lecture 15: Stress and Growth
1. Prenatal Environment
1. FOAD
1. fetal origins of adult disease
2. Fetal environment predicts significantly the adult diseases you will or won't have
2. Fetal Stress
1. What the mother experiences the baby experiences
2. They will both have stress
3. Dutch Hunger Winter
1. 2nd and 3rd trimester is when metabolism is programed for the baby.
2. Lack of nutrients means the baby will have a thrifty metabolism to adapt to famine.  They will store food and will be more likely to have obesity.
3. This is passed on to kids and grandkids
2. Responsive Brain Video clip
1. Defined
1. Baby got messages gained weight quicker and got discharged earlier
2. Jan Berry stressed dwarfism
3. Orphans that have been psychologically deprived and then placed into a loving family will grow 10 inches in a year and thrive
4. Fish
1. environment impacts physiology
2. Mechanisms
3. Postnatal Environment
1. Epigenetics
2. Environment
6. Lecture 16: Stress management relaxation
1. Basic Concepts and Practice
1. Concepts
2. Regular practice
3. Website
2. Body Focused Relaxation Techniques
1. Breathing
2. Body scan
3. Prog muscle
3. Mind Focused relaxation techniques
1. Visualiz
2. Auto
3. Self
7. Lecture 17:  Stress and Health Pain & Memory
1. Physical Pain
1. Definition
2. Pathway
3. Gate Control Theory
1. Hypothesized to be in the spine
2. If you are more anxious you are more sensitive to pain
3. Closing the Gate
1. Social Support
2. Acute stress can blunt pain (
2. Social Pain
1. Eisenberger
1. Social pain lights up the same areas in the brain as physical pain
2. Tylenol
1. Gave tylenol for 3 weeks and they found that people feel better socially because they were less hurt by social pains
3. Memory
1. Acute Stress: increases memory
2. Chronic Stress: decreases memory
8. Lecture 18: Stress Management - Self-talk basics
1. Basics
1. Concepts (perception, narrative
2. Practice
2. Self-Talk
1. Automatic thoughts
2. Schemas:since childhood you look at the world in a way that is not always adaptive
3. Mediation
1. Concepts
1. This can be hard for religious people because it is difficult to be accepting and let things go
2. Religiosity
1. Gratitude, compassion, and forgiveness
1. Forgiving people are much less stressed because they can let go of anger
2. The person you really punish is yourself when you are unforgiving
3. Forgiveness is really a religious concept
9. Lecture 19: Stress and Health - Sleep and Aging (today is on the test)

382: Stress & Health - Sleep and Aging

SLEEP

REM Sleep
Why is REM sleep called paradoxical sleep?  It is because you are paralyzed.  Your brain is extremely active during REM sleep so this paralysis is something that is essential for us to keep us from acting out these activities.

Consolidation
We consolidate our memories during our sleep.  The brain is exercising pathways that were underused during the day.  If you don't get adequate REM then you will mess up your cognition which means you will not learn or remember things as well.

Limbic System & Dreaming
The limbic system is active during REM sleep which contributes to our dreams being full of emotional content.  The prefrontal cortex is inactive during sleep which contributes to the impracticality of dream content.

Sleep Deprivation: Stress
Sleep deprivation is a stressor.  Delta sleep factor is a corticotropin inhibiting hormone which means that CIH inhibits glucocorticoids or CRF. When you have elevated glucocorticoid levels you sleep onset will be disrupted and it will also disrupt energy restoration in your brain.  This creates a vicious cycle of stress decreasing sleep and lack of sleep making it you feel more stress (this contributes to insomnia).  Anticipating poor sleep increases glucocorticoids.

AGING

As humans we have this idea that as we get older we just naturally get more fragile.  However, many species do not age and throughout their life they have about the same amount of health and then they die.  But mammals seem to have a more obvious aging process.  Why does this happen?

As humans we are very adaptive in our earlier ages.  But this adaptation often has a cost associated with it which makes us much more susceptible to disease later in life.

No Free Lunch Hypothesis
This is basically the idea that evolutionarily, to propagate our genes, we are very adaptive to change in the early stages of our life but eventually we pay the bill by aging later in life.  Negative pleiotropy is the notion that a genetic trait give you advantages earlier in life at the cost of disadvantages later on.

Stress
Aging is a time of life when organisms don't deal with stress very well.  Mistakes are made in copying DNA with creation of new cells which happens frequently.  Lots of stress through the lifetime can accelerate the aging process.  So what you see is that lack of stress can cause the body itself can act as a stressor.  Just being alive is stressful for mammals.

In humans glucocorticoids levels stay about the same until extreme old age and then rises with age.  They have found that the amount of glucocorticoids released during stress does not change with age and the recovery time from stress increases.

Biological Processes
Neurogenesis in hippocampus decreases with aging.  They have also found that if you give someone an anti-cortisol pill then their hippocampus will improve.  It will increase neurogenesis in the hippocampus to help fight against the decrease in neurogenesis caused by aging.  

375: Semantic Memory Pt2

MODELS OF MEMORY ORGANIZATION

There is a similarity idea that we organize things in terms of similarities.  This can account for typicality effects.  So if he gave you a few hundred star constellation pictures after a while if you get a new picture you will be able to categorize things because you will have a mental representation of the average of all the constellations you have seen.

375: Semantic Memory Pt1

SEMANTIC MEMORIES

So far we have talked about episodic memories which are memories about events in your life.  Semantic memories are memories for factual types of information such as "who was the first president of the United States."  We all know who it is but we don't have a specific event in memory of when we learned this information.

ORGANIZATION OF SEMANTIC MEMORY

How do you organize your memories?  Is it nice and organized or maybe more like a bunch of random piles of information.  Theories of how we organize this need to account for accessing relevant information when crucial information is not stored.

Something very impressive is that we can use our semantic memories in novel ways.  For example if we were to drop an egg off of the Eifel Tower would it break?  Well we know that it would break because we can use other semantic information that we have and use it in a flexible way.

CATEGORIZATION

1. Categorization
1. Semantic Memory
1. Category VS Exemplar: group of objects that have something in common VS particular instance of a category
2. Concept: Mental representation to compare to novel object
3. Generalization: ability to gather info about one exemplar and compare it to another
4. Typicality effect
1. Effects how quickly you categorize and how you reason about things
2. How do you know if something is typical?
5. Typicality - levels
1. Basic level (e.g., "Maple")
1. most inclusive but members still share most of their features
2. Superordinate level (e.g., "Trees")
1. category is one level more abstruse; winged or not, tailed or not, warm blooded or not...
3. Subordinate level (e.g., "Sugar Maple")
1. categories are less abstract than basic level
6. Some people argue that the basic level is psychologically privileged.
1. This means that when we are thinking about cars what we imagine is on a basic level

370: Binocular Cues

ANGULAR DISPARITY

Angular disparity is the difference between the angle of light hitting the retina in the right eye minus the left eye.  For all the angles that = 0 degrees creates what is known as the horopter.  The horopter is an imaginary line around you where there is 0 disparity between your two eyes.  Well what about things closer than the horopter.

Closer than the Horopter (Crossed)
Things that are closer yield what is known as cross disparity which is a disparity that is greater than 0.  The closer something is the more cross disparity there will be.  With a magic eye illusion if you focus closer than the horopter you will see the image pop out towards you.

Further than the Horopter (Uncrossed)
Things that are further away yield disparity that is less than 0 and it is known as uncrossed disparity.  The further away something is the more negative the disparity will be.  With a magic eye illusion if you focus further than the horopter you will see the image pop out away from you.

STEREOPSIS

Your brain is seeing two different images (angular disparity) but through stereopsis these two images are fused.  This fusion gives you very fine depth information but the degree of depth information depends upon the amount of disparity between the two images.  So for example, if you have one image taken from above an object, say from space, then you will not be able to see depth.  However, if you instead take two images and present those two pictures to two different eyes you will then be able to see depth of objects.

CORRESPONDENCE PROBLEM

This is the problem that if we are seeing two different images in our eyes how is it that we are able to line those images up to perceive only one image.  It is a matter of what depth you would need to focus on in order to get the two images to line up.  Usually we solve this by things like, images correspond if they are on the same horizontal plane.  We really don't know how the correspondence problem is solved by the brain.

A Study
When people were presented with random patterns and told that some of the patterns had a face and some did not about 40% of the time people would say they saw a face when there wasn't actually a face there.  The researchers took the average of all the ones they said there was a face and the ones where they said there was not a face and they found that there was a face in this average and people will pick up on this pattern and do so consistently.