Light

Question 1

Johannes Müller (1801–1858)

Answer 1

DOCTRINE of SPECIFIC NERVE ENERGIES –> nature of a sensation depends on which neurons are active, and not on how the neurons are stimulated.

Question 2

Charles Sherrington (1857–1952)

Answer 2

Neurons not physically connected, but work in networks

Question 3

Wilder Penfield (1891–1976)

Answer 3

Stimulating neurons in certain regions of the brain lead to patients feeling sensation of touches on their body.

Question 4

Horace Barlow (1921 - )

Answer 4

Neuron doctine (1972): perception depends on a combination of specialized neurons, each selective for a particular stimulus attribute.

Question 5

The brain has a __ organization

Answer 5

modular

Question 6

The sensory modalities have __ receiving areas:

Answer 6

primary

Question 7

Some areas of the brain that are __, meaning that information from several senses is combined

Answer 7

Polysensory

Question 8

Hermann von Helmholtz (1821–1894) invented the

Answer 8

ophtalmoscope

Question 9

Helmholtz argued:

Answer 9

That all behaviour could be explained by only physical forces (materialism)

Question 10

How did hermann von helmholtz prove that all behaviour could be explained by only physical forces:

Answer 10

he measured the speed of the neural impulse and proved that neurons obey the laws of physics and chemistry

Question 11

Santiago Ramón y Cajal (1852–1934)
created :

Answer 11

Incredibly detailed drawings of neurons and neural structures

Question 12

Santiago Ramón y Cajal (1852–1934)

Answer 12

Was the first person to discover the synapse

Question 13

Santiago Ramón y Cajal (1852–1934) won

Answer 13

the nobel prix in

Question 14

microelectrodes are used to record:

Answer 14

neuronal activity from single neurons

Question 15

Describe how microelectrodes are placed:

Answer 15

• Recording electrode is inside the nerve cell
  -Null electrode is outside the fibre
  -Difference in charge between null and recording electrode is -70 mV
  -This negative charge of the neuron relative to its surroundings is the resting potential

Question 16

Action potentials remain:

Answer 16

the same size

Question 17

Increase in stimulus intensity can increase the

Answer 17

firing rate of neurons

Question 18

Electroencephalography (EEG)

Answer 18

A technique that, using many electrodes on the scalp, measures electrical activity from populations of many neurons in the brain

Question 19

Event-related potential (ERP)

Answer 19

A measure of electrical activity from a subpopulation of neurons in response to particular stimuli that requires averaging many EEG recordings

Question 20

Visually Evoked potentials (VEP):

Answer 20

A measure of electrical activity from a sub population of visual neurons in response to a visual stimulus.

Question 21

Magnetoencephalography (MEG):

Answer 21

A technique, similar to EEG, that measures changes in magnetic activity across populations of many neurons in the brain

Question 22

Computerized tomography (CT):

Answer 22

An imaging technology that uses X-rays to create images of slices through volumes of material (e.g., the human body)

Question 23

Magnetic resonance imaging (MRI):

Answer 23

An imaging technology that uses the responses of atoms to strong magnetic fields to form images of structures like the brain

Question 24

Positron Emission tomography (PET):

Answer 24

functional neuroimaging technique based on measurement of changes in blood flow associated with brain activity, using a radioactive substance introduced into the blood.

Question 25

Functional Magnetic Resonance Imaging (fMRI)

Answer 25

A variant of MRI that
makes it possible to measure localized patterns of activity in the brain.

Activated neurons provoke increased blood flow, which can be quantified by measuring changes of oxygenated and deoxygenated blood to strong magnetic fields

Question 26

Blood oxygen level-dependent (BOLD) signal

Answer 26

The ratio of oxygenated to deoxygenated hemoglobin that permits the localization of brain neurons that are most involved in a task

Question 27

Visible spectrum for humans ranges from

Answer 27

400 to 700 nanometers.

Question 28

Energy is described by:

Answer 28

wavelength

Question 29

Spectrum ranges from

Answer 29

short wavelength gamma rays to long wavelength radio waves.

Question 30

Most perceived light is

Answer 30

reflected light i.e. bounces off objects within out environment.

Question 31

Light can be (5):

Answer 31

absorbed, scattered, reflected, transmitted, or refracted

Question 32

Absorbed

Answer 32

Energy (e.g., light) that is taken up, and is not transmitted at all

Question 33

Scattered:

Answer 33

Energy that is dispersed in an irregular fashion

• When light enters the atmosphere, much of it is absorbed or scattered and never makes it to the perceiver.

Question 34

Reflected:

Answer 34

Energy that is redirected when it strikes a surface, usually back to its point of origin

Question 35

Transmitted:

Answer 35

Energy that is passed on through a surface (when it is neither reflected nor absorbed by the surface)

Question 36

Refracted:

Answer 36

Energy that is altered as it passes into another medium, (e.g., light entering water from the air)