science section 5 - Technology & neuroscience

Question 1

which scientist used early microscopes to see individual neurons in the brain?

Answer 1

santiago ramon y cajal

Question 2

what was the goal of the brain research through innovative technologies (BRAIN) project?

Answer 2

to give scientists the resources they needed to get a “dynamic picture of the brain in action”

Question 3

Human connectome project

Answer 3

the largest map of neural circuits structure

Question 4

perturbing (The brain)

Answer 4

changing something in the brain and seeing how cells in the brain/subject behavior changes in response

Question 5

lesion studies

Answer 5

damaging part of the brain and seeing how the subject then interacts with the world. still done on animals

Question 6

paul broca

Answer 6

met a patient with an extreme speech impediment. Broca later did an autopsy on this patient, and found that the patient had a massive lesion in the left side of his brain. led broca to believe that speech and language areas are localized on the left side of the brain.

Question 7

electrical brain stimulation

Answer 7

implanting an electrode into the brain and stimulating a certain region; led to important treatments such as electroshock therapy

Question 8

transcranial direct current stimulation (tDCS)

Answer 8

uses a positive and negative electrode on the scalp to change brain activity. stimulation created with this is very small

Question 9

optogenetics

Answer 9

genetically modifying a neuron to have a ChR2 gene, which manifests as an ion channel that depolarizes in light. in this way, scientists can trigger an action potential just with light and be highly specific about which neuron they’re targeting.

Question 10

transcranial magnetic stimulation (TMS)

Answer 10

creates an electric field within the cortex, causing neurons in the targeted region to turn “on” or “off”. used to confirm what brain regions correlate to what functions (e.g. if a subject can’t speak when the left side of their brain is “turned off”, then left side must correlate with speaking.)

Question 11

pro of TMS

Answer 11

can target a small area without spread

Question 12

con of TMS

Answer 12

can only stimulate brain regions near the surface

Question 13

intracellular/single-unit recording

Answer 13

implanting an electrode in one neuron and recording changes in membrane potential; hard bc neurons are small

Question 14

extracellular recording

Answer 14

electrode measures membrane potential from a population of cells, not just one

Question 15

phrenology

Answer 15

developed by Franz Joseph Gall, who believed you could determine traits and abilities by feeling bumps on a subject’s skull. this pseudoscience was used to justify belief that some people are inferior (e.g. enslaved people in America)

Question 16

theory of localization

Answer 16

idea that particular areas of the brain have particular jobs to do

Question 17

electroencephalogram (EEG)

Answer 17

developed by Hans Berger. he originally stuck metal wires directly into brain, but today electrodes are just stuck to the scalp.

Question 18

whats the EEG used for?

Answer 18

electrodes record electrical impulses of a large population of neurons. Berger used it to show differences between electrical activity of healthy brain vs irregular brain (e.g. one with epilepsy)

Question 19

dipole

Answer 19

most neurons in an area have similar charges, creating a dipole, an area of positive charge next to an area of negative charge.

Question 20

Event related potential (ERP :P)

Answer 20

an electrical potential that directly results from a stimulus; ERP experiments record EEG activity at certain times to track neural response to events/stimuli

Question 21

cons of EEG

Answer 21

only for outermost brain areas, and poor spatial resolution (can’t really pinpoint where in brain certain activity is coming from)

Question 22

Magnetic resonance field imaging (MRI)

Answer 22

medical imaging technique that produces a strong magnetic field to generate map of inner body

Question 23

what is the process of an MRI scan?

Answer 23

1.) patient lays inside
2.) strong magnetic pulses align the protons in the patient’s body 3.) until a radio frequency (RF) momentarily disrupts this alignment
4.) the atoms gradually float back into alignment which emits a radio signal that the MRI can measure

Question 24

what does the magnet component do in an MRI?

Answer 24

generates magnetic field

Question 25

what do the gradient coils do in an MRI?

Answer 25

allow the scanner to assess where a particular signal is coming from

Question 26

what do the radio frequency coils do in an MRI?

Answer 26

produce the radio frequency (RF) pulse

Question 27

deoxygenated

Answer 27

red blood cells not carrying oxygen. these have different magnetic properties from those that are carrying oxygen.

Question 28

functional MRI (fMRI)

Answer 28

creates maps of what brain areas are active during different activities. if a brain region has oxygenated blood flowing to it, then it is probably related to whatever activity the person is doing. scientists can tell where oxygenated blood is going because it stands out on an MRI scan (remember it has different magnetic properties from deoxygenated blood cells!)

Question 29

fusiform face area

Answer 29

tiny region in temporal lobe that is very active when person is looking at faces. would not have been discovered without fMRI.

Question 30

brain computer interface

Answer 30

a system that allows a person to control a device by way of implanted electrodes. still experimental

Question 31

invasive methods of brain computer interface

Answer 31

any involving brain implants. electrocorticography, local field potentials, multi-unit activity, sing-unit activity.

Question 32

non-invasive methods of brain computer interface

Answer 32

any surface detectors. EEG, fMRI, near-infrared spectroscopy (NIRS)

Question 33

computational neuronal modeling

Answer 33

use of computer algorithms or simulator programs to model behavior of neurons and understand their processes. these mimic existing network of neurons in brain.

Question 34

what can computational neuronal modeling do?

Answer 34

simulate the interactions between multiple neurons in a larger neuronal network

Question 35

artificial neural networks

Answer 35

give computers the ability to perform tasks that a human would typically do (e.g. a self driving car can spot pedestrians with enough accuracy to avoid them)

Question 36

deep neural network

Answer 36

neural network that is capable of complex problem solving (e.g. the neural network that beat Europe's champion at Go in 2015)

Question 37

computational psychiatry

Answer 37

researchers argue that adding computer algorithms to patient descriptions and behavioral testing could provide more data about psychiatric patients and provide clinicians with vital tools to improve diagnosis; fast-growing field

Question 38

what's the goal of computational psychiatry?

Answer 38

improve patients’ responses to treatment, improve patients’ adherence to therapeutic drugs, and improve patient outcomes