Flashcards in Brain Myths Episode 5: How Different Are Male And Female Brains? Deck (6)
Brain size varies in both sexes. Sometimes male brain is larger; other times female’s is larger. Size is not that relevant. Quality of gray matter makes the difference.
Cortical thinning is normal healthy neural pruning during development. A thick cortex could be schizophrenia. Later in life Cortical thinning could be a sign of atrophy in the first signs of dementia. The brain is a moving target. It’s strength lies in its plasticity, which is limited by biology.
Gender defined: the cultural or social construct with which a person identifies. Sex and gender have never been black and white distinctions but the public treats them as such. A person sex identity is not easily categorized as a male or female. (MN: in other words they do not lineup in both the brain and the body. )
Ergo, The transgender person having a sex change to psychologically line up the brain and their anatomy.
Female brains are wired differently than male brains. Female brains have more gray matter and male brains have more white matter.
White matter is the stuff that connects the neurons. Women are not more emotional than men. Albeit, women express their emotions much more pronounced.
Women suppress anger in public but let it all out in private. Alzheimer’s disease: Females are more prone to have it than males.
Place notes and comments here.
These lectures are given by Dr. Indre Viskontas, PhD. Of San Francisco University.
Episode number six: how accurate is your memory.
The Bloodsworth case. The Bloodsworth case was the first case of overturning a death row conviction with DNA. Bloodsworth had spent nine years in prison because of five eyewitnesses!
Number 1: Our process of remembering is suggestible and easily manipulated. In other words, remembering is subjective.
Number 2: Our confidence in our memory is not a good proxy for how accurate it is.
Autobiographical memory, is memory for the events of our lives. Every time you recall a memory, you rewrite the whole memory again including the new changes you just made to it.
How autobiographical memory works.
It starts in the Medial temporal lobe, then passes into the “Entorhinal cortex”. Here it begins a conscious memory trace.
Note: it is this region that is often first affected by Alzheimer’s disease.
Pathology: this is why Alzheimer’s disease starts affecting long-term memories what happened 10 minutes ago is a long-term memory.
Working memories or what we are doing right now. Like looking for a bathroom in the shopping mall directory. You find a bathroom but must keep on rehearsing it or else it evaporates in the memory is gone!
Alzheimer’s victims are stuck in working memory the right now, and cannot remember they just asked use the same question two minutes ago. This is happening because the Entorhinal cortex is not functioning properly.
When the end of mental cortex is working properly, it sends sensory info to the hippocampus. The hippocampus is comparing the new info with what was stored in the past as an old memory. Then it rewrites a confabulation mixture of old and new memory which is replacing your old original memory with the new version.
So with Alzheimer’s disease the victim is stuck in working memory (short term memory) and cannot access the old memory of just asking you the same questions two minutes ago.
Now what happens in a normal brain is you already created a new long-term memory of your high school graduation ceremony. You retell the ceremony story later to friends and someone cracked a funny remark. When you sleep that night, the Medial temporal lobe, which houses your hippocampus, amygdala, etc., evaluates the funny memory with the original memory which results in a new rewritten confabulation including the funny joke with your original long-term memory of the high school graduation ceremony. This explains why we overwrite a memory each time we recall it.
Episode #8: Do you perceive the world as it really is?
Don’t believe your eyes!
The idea that we see the world as it really is—this is a myth. The human eye has about one megapixel of resolution. My smart phone has resolution of eight megapixels. That is eight times better vision than my eyes!
To get around this problem, it concentrates a sampling of your field of vision into where you can actually focus your eyes.
Hold out your thumb at an arms length and look at it. The thumb is all you can focus upon; what you can actually see with your eyes. Everything else in your vision is a crude sampling that we call peripheral vision. You cannot see well enough to read a paper beside your thumb. Your brain confabulates what it thinks should be there. This is called tunnel vision.
We do not see automatically. We learn to see. We see with our brain. Our brain interprets the photon signals and gives us a vision of what it thinks you were looking at.
Case in point, the story of “Virgil”.
Virgil had thick cataracts in both eyes and was nearly blind since childhood. Right before his wedding, his cataracts were removed after living with them for 40 years of blindness. Virgil’s first sighting was of his future bride to be.
Virgil site was a confusing blur of colors with no focused image to see. His eyes worked fine. It was his upstream visual cortex that was not functioning as it should. We actually “learn to see” when we are a baby.
Virgil’s version was like that of an infant the image was not re-created in his brain, therefore it was a blurry mixture of colors without the form of a re-created image. This is called face blindness. “Prosopagnosia”.
Other problems Virgil had:
1: No depth perception.
2: He didn’t know about his own shadow and was scared of it following him around.
3: Virgil could not see in three dimensions everything was flat no height width or depth.
4: Virgil could not use steps, he had no dimensional vision. Everything was flat.
Blindspot‘s. We all have a blind spot in our right now because of the cortex going through it. Yet we don’t see it because our brain confabulates what it thinks would be there and just fills in the empty spaces.
(My note: remember for us to see with focus on our entire vision field, we would need something like a buffering circle on a computer screen until vision could be fully drawn for us.)
Example of a person not able to detect motion. Very strange.
In the book called “an anthropologist on Mars”, the author Oliver Sacks 1933-2015 details the case.
1: Couldn’t Pour coffee in a cup because she could not see it filling up.
2: People in the room would be say 30 feet away, then instantly right next to her like they were just suddenly beamed there. People just disappear and then reappear in another room a few seconds later.
3: Couldn’t cross the street because a car that was a block away was suddenly right in front of her.
Episode #9: Is your brain too smart for magic tricks?
(MN: Your entire concept of reality is simply made up in your own brain. Self awareness, vision, sounds, colors, sensations, and being a sentient being.
Your whole world is made up in your brain. A good book that I have read is called “fooling you is what your brain does for a living.”
Indre Viskontas’s quote, “ our senses do not just make stuff up right? What we experience is really out there somewhere right?”
But that is all just an illusion!
We can only concentrate on a small amount of sensory input. Therefore our brain will focus on one part or the other and simply ignore the bulk of sensory information.
The brain will quickly make a decision on what it thinks is the most important and focus on that part automatically. This is called “top down processing”
This is how magicians trick us.
In attentional blindness-the gorilla lady nobody sees.
We are focused on counting the times the ball is passed and completely blind to the gorilla suit in the middle of the picture. We don’t see the gorilla because our brain doesn’t think it is important, therefore it never creates a re-image of the gorilla for us to see.
(This is because our brain is focused on the ball tossing.)
(MN: This is the same principle of not finding the golf ball, then suddenly here it is right under our nose!”)