chap-2 cognitive neuroscience

Question 1

cognitive neuroscience?

Answer 1

the study of physiological basis of cognition.

Question 2

levels of analysis?

Answer 2

a topic can be studied in a number of different ways.

Question 3

nerve net?

Answer 3

continues chain of nerves in a complex pathway for conducting signals uninterrupted through the network.

Question 4

neuron’s doctrine?

Answer 4

by using the Camillo Golgi’s stain (thin slice of brain immersed with silver nitrate) to study the nerve net of baby animal. Discover that net is not continues but individual unites.

Question 5

nerve net theory?

Answer 5

the individual cells transmit signals in the nervous system, and that these cells are not continuous.

Question 6

neural circuits?

Answer 6

interconnectedness of specific neurons.

Question 7

who first recorded the electrical signal from a sensory neuron?

Answer 7

Edger Adrain.

Question 8

why action potential is the best to send signals throughout the brain?

Answer 8

because it doesn’t change the shape or height.

Question 9

neurotransmitter?

Answer 9

released chemical in the synapse in response to action potential.

Question 10

quality across the sense vs quality within senses?

Answer 10

different experience associated with each senses.
quality within sense (in vision, shape, brightness, color, etc.

Question 11

the principle of neuron presentation?

Answer 11

everything that a person experience is based on the representation in the person’s nervous system.

Question 12

what was the discovery by the recording of neurons outside the visual cortex?

Answer 12

1. many neurons at higher level of the visual system fire to complex stimuli like geometrical patterns and faces.
2. a specific stimulus causes neural firing that is distributed across many areas of the cortex.

Question 13

feature detectors?

Answer 13

neurons that responded to specific stimulus features such as orientation, movement, and language.

Question 14

experience-dependent platicity?

Answer 14

structure of the brain is changed by experience.

Question 15

hierarchical processing?

Answer 15

the progression from lower to higher areas of the brain.

Question 16

problem of sensory coding?`

Answer 16

the problem of neural representation for the senses.

Question 17

sensory code?

Answer 17

how neurons represent various characteristics of the environment

Question 18

specificity coding?

Answer 18

object could be represented by the firing of a specialized neuron that responds only to that object.

Question 19

population coding vs sparse coding?

Answer 19

representation of a particular object by the pattern of firing of a large number of neurons. (P.C)
particular object is represented by a pattern of firing of only a small group of neurons, with the majority of neurons remaining silent. (S.C)

Question 20

localization of function?

Answer 20

specific functions are served by specific areas of the brain.

Question 21

neuropsychology?

Answer 21

the study of behavior in people with brain damage.

Question 22

cortical equipotentaility?

Answer 22

the brain operated as an indivisible whole as opposed to specialized areas.

Question 23

Broca’s aphasia vs Wernicke’s aphasia?

Answer 23

Broca’s aphasia: understand the speech but can’t speak.
Wernicke’s aphasia: can’t comprehend but can speak fluently
but meaningless.

Question 24

prosopagnosia?

Answer 24

inability to recognize faces.

Question 25

which area of the brain is responsible to recognizing faces?

Answer 25

fusiform face area (FFA) in the underside of the temporal lobe.

Question 26

parahippocampal place area?

Answer 26

PPA associated with spatial area when looking at a picture and room.

Question 27

Extrastriate body area

Answer 27

EBA is activated by pictures of bodies and parts of bodies.

Question 28

distributed representation?

Answer 28

activation of neurons in different parts of the brain upon looking at a fact.

Question 29

episodic/semantic memories?

Answer 29

episodic memory: life events
semantic memory: facts.

Question 30

neural network?

Answer 30

interconnected areas of the brain that can communicate with each other.

Question 31

what is the 4 principle of neural network?

Answer 31

1. there are complex structural pathways called networks that form the brain’s information highway.
2. within these structural pathways there are functional pathways that serve different functions
3. these networks operate dynamically, mirroring the dynamic nature of cognition.
4. There is a resting state of brain activity, so parts of the brain are accive all the time, even when there is no cognitive activity.

Question 32

structural connectivity?

Answer 32

the brain’s wiring diagram created by nerve axons that connect different brain areas.

Question 33

Track-weighted imaging?

Answer 33

TWI is based on detection of how water diffuses along the length of nerve fibers.

Question 34

connectome?

Answer 34

structural description of the network of elements and connections forming the human brain OR the wiring diagram of neurons in the brain.

Question 35

functional connectivity?

Answer 35

the extent to which neural activity in two brain areas are correlated.

Question 36

time-series response?

Answer 36

indication of how the response changes overtime.

Question 37

six common functional network? VEDDSS

Answer 37

1- Visual: vision; visual perception (occipital lobe)
2- somato-motor: movement and touch (parietal lobe)
3- Dorsal Attention: attention to visual stimuli and spatial locations (prefrontal, parietal and occipital lobe)
4- executive control: higher-level cognitive tasks involved in working memory and directing attention during tasks (prefrontal, parietal, and occipital lobe)
5- Salience: attending to survival-relevant events int he environment (prefrontal and parietal lobe)
6- Default mode: mind wandering, and cognitive activity related to personal life-story, social functions, and monitoring internal emotional states. (temporal, prefrontal, and parietal lobe)

Question 38

default mode network?

Answer 38

a network that was activated when people were not engaged in the activity. wondering and side tracking of the attention while doing a task.

Question 39

voxel

Answer 39

activity is recorded in Voxel (small cube shape area in brain 2mm, small unit of analysis created by fMRI , not the actual structure of the brain.

Question 40

functional connectivity vs structural connectivity?

Answer 40

Structural connectivity: connected by structure/ wires
functional: connected by wifi, function communication through neural pathways.

Question 41

Resting potential?

Answer 41

o cell is polarized = at rest, the inside of neuron is more negatively charged (ion concentrations) than the outside by about -70mV.

Question 42

Action potential?

Answer 42

Ø when a neuron “fires”, the ion concentration changes along the axon
Ø depolarization of cell membrane = the inside-outside axon difference in ion concentration reverses to +40mV
Ø propagated response = depolarization travels down axon without decreasing in size
depolarization is immediately followed by repolarization in that same area

Question 43

Name the major techniques to study the brain?

Answer 43

• Localization of Function = specific cognitive functions are supported by

Destruction & Stimulation
Brain Structure
Brain Activity

Question 44

studying the brain through destruction?

Answer 44

Animal Studies (majority of studies)
Ø Ablation = remove portion of the brain (animal studies), see the impact on functioning.
Ø Lesion = focused damage in specific area/ removal
o Usually use tiny electrodes > focused damage (animals)
o Damage produced by heat/cold/electricity/chemical

Question 45

Studying brain through stimulation?

Answer 45

• Stimulation of brain areas through mild electric current to see the changes in behavior.
  Can enhance or disrupt cognitive functions associated with brain area depending on the stimulation and the area.

Question 46

Wilder Penfield?

Answer 46

(the first neural surgeon that did the awake-brain surgery).
* stimulated brain of awake patient during brain surgery (invasive)
* no pain receptors in CNS (so local anesthetic is fine)
* patients describe their sensations, and surgeons note changes in behavior
* some places, stimulation caused movement of limbs, or the report of feeling a light touch, hearing a melody, or the smell of a rose.

Question 47

Major Techniques to study brain’s structure?

Answer 47

1. CAT / CT
2. MRI
3. EEG
4. fMRI

Question 48

CAT/ CT?

Answer 48

• computerized (axial) tomography (CAT/CT): take images of slices of brain, then piece slices together to create a 3D image of the brain
  Ø similar to very powerful x-ray
• utility: reveals localized brain tumors and lesions
• Advantages
  o instantaneous
  o non-invasive
• Disadvantages
  o exposure to radiation
  o poor spatial resolution, can’t specify about the exact area of the brain.
  Can’t differentiate between the white and grey matter.