Autodidact: self-taught

Apr
24
2012

M

by V. L. Craven

Mind Hacks by Tom Stafford and Matt Webb
MoinMoin Python WikiClone http://moin.sourceforge.net
Recommended reading: Phantoms in the Brain: Probing the Mysteries of the Human Mind by V.S. Ramachandran
-01- p2: Cognitive Psychology is the psychology of basic mental processes—things like perception, attention, memory, language, decision-making. It asks the question, ‘What are the fundamental operations on which mind is based?’

-02- pp3-4: People aren’t consistent in the same way software or machines usually are. Two sources of variability are noise and learning. We don’t automatically respond in the same way to the same stimulus every time. This sometimes happens for no apparent reason, and we call this randomness noise. But sometimes our responses change for a reason, not because of noise, and that’s because the very act of responding first time around creates feedback that informs our response pattern for the next time…
-03- p4: For cognitive psychologists, why you think you did something is just another bit of data, no more privileged than anything else they’ve measured, and no more likely to be right.
–A psychologist called Daryl Bem formalized this in ‘self-perception theory.’ He said “Individuals come to know their own attitudes, emotions, and internal states by inferring them from observations of their own behaviour and circumstances in which they occur. When internal cues are weak, ambiguous or uninterpretable, the individual is in the same position as the outside observer.’ Bem, D.J., “Self Perception Theory.” In L. Berkowitz (ed.) Advances in Experimental Psychology, volume 6 (1972).
-04- p5: An electroencephalogram (EEG) produces a map of the electrical activity on the surface of the brain. Fortunately, the surface is often what we’re interested in, as the cortex—responsible for our complex, high-level functions—is a thin sheet of cells on the brain’s outer layer.
-05- p6: Positron emission topography (PET) is more invasive than any of the other imaging techniques. It requires getting a radioactive chemical into the blood-stream (by injection) and watching for where in the brain the radioactivity ends up—the ‘positron emission’ of the name. …
When neurons fire to send a signal to other neurons, they metabolize more energy. A few seconds later, fresh blood carrying more oxygen and glucose is carried to the region. Using a radioactive isotope of water, the amount of blood flow to each brain location can be monitored, and the active areas of the brain that require a lot of energy and therefore blood flow can be deduced.
-06- p7: [Regarding Functional Magnetic Resonance Imaging (fMRI)] : The magnetic field pushes the hydrogen atoms in your brain into a state in which they all ‘line up’ and spin at the same frequency. A radio frequency pulse is applied at this exact frequency, making the molecules ‘resonate’ and then emit radio waves as they lose energy and return to ‘normal.’ The signal emitted depends on what type of tissue the molecule is in. By recording these signals, a 3D map of the anatomy of the brain is built up.
-07- p8: Transcranial magnetic stimulation (TMS) isn’t an imaging technique like EEG or fMRI, but it can be used along with them. TMS uses a magnetic pulse or oscillating magnetic fields to temporarily induce or suppress electrical activity in the brain….
Neurons communicate using electrical pulses, so being able to produce electrical activity artificially has its advantages. Selected regions can be excited or suppressed, causing hallucinations or partial blindness if some part of the visual cortex is being targeted.
-08- p9: “Savant for a Day” by Lawrence Osbourne—an article in the New York Times, which describes Lawrence Osbourne’s experience of TMS, having higher-level functions of his brain suppressed, and a different type of intelligence exposed.
-09- p9: Neuropsychology is the study of what different parts of the brain do by studying people who no longer have those parts. As well as being the oldest technique of cognitive neuroscience, it refutes the oft-repeated myth that we only use 10% of our brains.
-10- p10: Two distinct language processing regions in the brain: Broca’s area (named after the neuropsychologist Paul Broca) is in the frontal lobe and supports understanding and producing structure in language. Those with damage to Broca’s area speak in stilted, single words. Wernicke’s area (on the junction between the temporal and parietal lobes and named after Carl Wernicke) supports producing and understanding that semantics of language. People with brain damage to Wernicke’s area can produce grammatically correct sentences, but often with little or no meaning, an incomprehensible ‘word salad.’ …
…there are no areas of the brain that are ‘black holes’–areas that never ‘light up’ in response to some task or other. Indeed, the neurons that comprise the cortex of the brain are active to some degree all the time, even during sleep.
… The human brain is a very expensive organ, requiring approximately 20% of blood flow from the heart and a similar amount of available oxygen, despite accounting for only 2% of body weight. …
-11- p11: Developmental studies indicate that neurons that are not employed early in life are likely never to recover and behave normally. For example, if the visual system is not provided with light and stimulation within a fairly narrow developmental window, the neurons atrophy and vision never develops. If the visual system is deprived of a specific kind of stimulation, such as vertical lines, it develops without any sensitivity to that kind of stimulus.
-12- p11: …the remarkable capacity of the brain to assign functioning to alternative areas if there are problems with the ‘standard’ areas during a specific time-point in development. Such “neuronal plasticity”, as it is known, is not seen following brain damage acquired in adulthood.
-13- p13: Senses and muscles all over the body are connected to nerves, bundles of neurons that carry signals back and forth. Neurons come in many types, but they’re basically the same wherever they’re found in the body; they carry electric current and can act as relays, passing on information from one neuron to the next. That’s how information is carried from the sensory surface of the skin, as electric signals, and also how muscles are told to move, by information going the other way.
Nerves at this point run to the spinal cord two by two. One of each pair of nerves is for receptors) a sense of touch for instance) and one for effectors—these trigger actions in muscles and glands. At the spinal cord, there’s no real intelligence yet but already some decision-making—such as the withdrawal reflex—occurs. Urgent signals, like a strong sense of heat, can trigger an effector response (such as moving a muscle) before that signal even reaches the brain.
-14- p13: This, with some other central regions, is known as the hindbrain. Working outward from the brain stem, the other large parts of the brain are the cerebellum, which runs behind the soft area you can feel at the lower back of your head, and the forebrain, which is almost all the rest and includes the cortex. Hindbrain activities are mostly automatic: breathing, the heartbeat, and the regulation of the blood supply.
The cerebellum is old brain—almost as if it were evolution’s first go at performing higher brain functions, coordinating the senses and movement. It plays an important role in learning and also in motor control: removing the cerebellum produces characteristic jerky movements. The cerebellum takes input from the eyes and ears, as well as the balance system, and sends motor signals to the brain stem.
Sitting atop the hindbrain is the midbrain… It acts partially to control movement, linking parts of the higher brain to motor neurons and partially as a hub for some of the nerves that don’t travel up the spinal cord but instead come directly into the brain: eye movement is one such function.
…The forebrain, also known as the cerebrum, is the bulbous mass divided into two great hemispheres—it’s the distinctive image of the brain that we all know. Buried in the cerebrum, right in the middle where it surrounds the tip of the brain stem and midbrain, there’s the limbic system and other primitive systems. The limbic system is involved in essential and automatic responses like emotions, and includes the very tip of the temporal cortex, the hippocampus and the amydala, and, by some reckonings, the hypothalmus. …
For us humans, the limbic system has been repurposed. It still deals with smell, but the hippocampus, for example—one part of the system—is now heavily involved in long-term memory and learning.
Online resources for brain anatomy: Brain Info http://www.med.harvard.edu/AANLIB/home.html
The Navigable Atlas of the Human Brain http://www.msu.edu/~brains/humanatlas
The Whole Brain Atlas: http://braininfo.rprc.washington.edu/mainmenu.html
Brain Voyager: http://www.brainvoyager.com
-15- p17: The wrinkles you can see on the outside [of the brain] are actually folds: the cerebrum is a very large folded-up surface, which is why it’s so deep. Unfolded, this surface—the cerebral cortex—would be about 1.5m2 (a square roughly fifty inches on the side), and between 2 and 4mm deep. It’s not thick, but there’s a lot of it and this is where all the work takes place. The outermost part, the top of the surface, is grey matter, the actual neurons themselves. Under a few layers of these is the white matter, the fibers connecting the neurons together. The cortex is special because it’s mainly where our high-level, human functions take place.
-16- p17 [Cerebral Lobes] You can cover the frontal lobe if you put your palms on your foreheaf with your fingers pointing up. It’s heavily involved in planning, socializing, lanuage and general control and supervision of the rest of the brain.
The parietal lobe is at the top and back of our head, and if you lock your fingers together and hook your hands over the top back, that’s it covered there. It deals a lot with your senses, combining information and representing your body and movements. The object recognition module for visual processing is located there.
You can put your hands on only the ends of the temporal love—it’s right behind the ears. It sits behind the frontal lobe and underneath the parietal lobe and curls up the underside of the cerebrum. Unsurprisingly, auditory processing occurs here. It deals with language too (like verbal memory), and the left hemisphere is specialized for this (non-linguistic sound is on the right). The curled up ends of the temporal love join into the limbic system at the hippocampus and are involved in long-term memory formation.
Finally, there’s the occipital lobe, right at the back of the brain, about midway down your head. This is the smallest lob of the cerebrum and is where the visual cortex is located.
The two hemispheres are joined together by another structure buried underneath the lobes, called the corpus callosum. It’s the largest bundle of nerve fibers in the whole nervous system.

M

My Wars are Laid Away in Books: The Life of Emily Dickinson by Alfred Habegger
001. ”Sad” may be the simplest and least pretentious of words she could have chosen for “secret sorrow” that had formerly obsessed her. What she now sees is that that sadness was willed or chosen—was something she dared to feel, and which called up a strength that in retrospect looks superhuman.
002. More imperious than ever, the poet turned most visitors away, saw a few by appointment, and always prescribed certain rituals that abolished both the casualness and the stupid conventionalities of ordinary social encounters. Within these limits, she was remembered as indescribably direct, fresh, fascinating, her terms being as generous as they were nonnegotiable.
003. There is never a hint of reproach, even when the subject is the poet’s distance from the world: “Sisters, I hear robins a great way off, and wagons a great way off, and rivers a great way off, and all appear to be hurrying somewhere undisclosed to me. Remoteness is the founder of sweetness.”
004. What she seeks is not marriage (clearly out of reach) but some sort of private, nonphysical union, which no one else need ever know about and in which she will always be the best little girl anyone could possibly wish for.
005. Accepting, embracing her exclusion from the public world, she redefined it as the freedom to do and be whatever she chose at home. Her way of living with Father was to create a private domain of friendship, thought, and art he could not enter.
006. Emily
“Things are not what they seem”
Night in Midsummer

A Library dimly lighted, three mignonettes in a little stand. Enter a spirit clad in white, figure so draped as to be misty, face moist, translucent alabaster, forehead firmer as of statuary marble. Eyes once bright hazel now melted & fused so as to be two, dreamy, wondering wells of expression, eyes that see no forms but glance swiftly to the core of all things—hands small, firm, deft but utterly emancipated from all claspings of perishable things, very firm strong little hands absolutely under control of the brain, types of quite rugged health. Mouth made for nothing and used for nothing but uttering choice speech, rare thoughts, glittering starry misty figured, winged words.
007. She said her life could be of no interest to others and denied anyone’s authority to speak for her.
008. ‘Such being the Majesty of the Art you presume to practice, you can at least take time before dishonouring it.’
009. ‘The tie between us is very fine, but a Hair never dissolves.’
010. ”To lose what we never owned might seem an eccentric Bereavement but Presumption has its Affliction as actually as Claim.” The idea (not so very far-fetched if you live in anticipation) was eventually molded into a nice paradox: “the parting of those that never met.”
011. The secretly cherished “relationship” was the fantasy that helped her devise a very real and powerful freedom.

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