L01 & 02 - Introduction to basic concepts in systems neuroscience

Question 1

Visual cortex can differ by ___% in individuals

Answer 1

300%

Question 2

Where are nociceptors found in the brain?

Answer 2

At the base of the brain and along major blood vessels - if you avoid those, you can cut through the brain or stimulate it without inflicting pain on the subject

Question 3

Primary visual cortex aka , area, striate _____

Answer 3

V1, area 17, striate cortex

Question 4

Lashley was searching for?

Answer 4

the engram - memory storage

*He trained animals to run mazes then lesioned different parts of brain. He re-run maze test 10 days later.

Question 5

Lashley’s 2 main findings in his search for the engram?

Answer 5

1) LARGE cortical lesions worked to destroy memory retention

2) SITE of lesion not important

Question 6

Lasheley’s 2 principles from his studies? What theory do they support?

Answer 6

1) Principle of MASS ACTION - memories stored diffusely throughout cortex
2) Principle of EQUIPOTENTIALITY - all parts of cortex play an equal role in memory storage

Support distributed theory

Question 7

Franz Josepf Gall - distributed or localised theory of brain function?

Answer 7

LOCALISED, phrenology (shape and size of cranium), each area of head has a specific mental function

Question 8

!Muller’s perspective

Answer 8

Nature of our perceptions depends on the nerves stimulated and NOT on the actual stimulus present - led to he idea of 1 to 1 mapping of end organs to parts of the brain (e.g. eye goes to one part of the brain, nerves from foot go to another)

Question 9

!Penfield’s study

Answer 9

The search for primary sites of epileptic seizures - discovered that the cortex is somatotopic

*Somatotopy is the point-for-point correspondence of an area of the body to a specific point on the central nervous system. Typically, the area of the body corresponds to a point on the primary somatosensory cortex (postcentral gyrus).

Question 10

LTP occurs when?

Answer 10

EPSP first (pre), AP second (post)

Question 11

!How does LTP occur?

Answer 11

• First there is depol. of NMDA R to remove Mg 2+ block then Glu binds leading to Na+ and Ca2+ influx
  1) Ca2+ enters NMDA R
  2) Ca2+ release from intracell. stores
  3) Activation of CaCam Kinase II
  4) Phosphorylate AMPA (increase conductance)
  5) Silent channels also activated
  6) Retrograde messenger leads to enhanced transmiter release

Question 12

Besides LTP, what is a possible explanation why humans > animals?

Answer 12

Neuronal recycling
e.g. Reading - words a child reads are words they have already heard
Writing - using something that is already there