Ch 1. Principles of signaling and organization

Question 1

neurobiology

Answer 1

consists of anatomy, physics, biochemistry, molecular biology, cognitive science and more

Question 2

the nervous system continuously…

Answer 2

-receives info
-analyzes it
-creates perception (meaning) around it
-makes decision
-acts and moves

Question 3

how does the NS act and move?

Answer 3

by producing coordinated and coherent muscle contractions

Question 4

Sensory neurons

Answer 4

translate sensory info into electrical signals that are then transmitted from one nerve cell to another across specific connections

Question 5

what does neurobiology try to do?

Answer 5

it tries to decode the info transmitted by signals

Question 6

How can neurobiology decode signals?

Answer 6

by determining where the signal came from, where it goes, the frequency and the temporal pattern
ex: signals in the optic nerve carry info from the retina.

Question 7

define the complexity of reading a book to demonstrate how complex the brain is even when it does seemingly simple things

Answer 7

• the brain needs to distinguish between black and white to make up the letters
  -the brain needs to take info from both eyes to make it into 1
  -the brain needs to make sure the image stays still even tho we are constantly moving
  -the brain must accurately calculate the distance between the hand and the page
  -the brain must comprehend what you are reading
  -the brain must remain focused long enough to complete the task
  -the brain has to keep you breathing, blinking, awake and aware
  -the brain has to hold your head and body up

Question 8

challenges in studying the NS

Answer 8

-dense packing of nerve cells
-intricacy of connections
-heterogeneous population
- ex. cells in the cerebellum tells us little about cells in the retina

Question 9

the brain creates perception, makes decisions and acts

Question 10

The complexity of perception

Answer 10

it requires the activation of multitude of cells and 1000+ neurons engaging in each stage of processes.

Question 11

fMRI

Answer 11

functional magnetic resonance imaging
can reveal locations of structures that activate given a task

Question 12

How does the NS create new messages that convey meaning?

Answer 12

it intergrates new information it gets from sensory nerves. Ex: sensory nerve in finger tips + previous knowledge/information = “i’m touching sandpaper”

Question 13

What did Santiago Ramon y Cajal do?

Answer 13

he was a great student of the NS
-mapped out the shapes and position of neurons
-mapped out origin and destination of its process in the neural network
-drew lots of photos of neurons using the golgi staining method

Question 14

what does the brain use to transmit information?

Answer 14

electrical signals

Question 15

what is the ultimate defining difference between a local graded potential and an action potential?

Answer 15

a change in voltage, if local graded potential meets the threshold, an action potential will fire

Question 16

what are two types of electrical signals the brain uses?

Answer 16

local graded potential and action potential

Question 17

local graded potential

Answer 17

spreads over short distance from origin
ex. you won’t feel a lego you just stepped on in your fingers
generated by extrinsic physical stimuli
ex. photoreceptors, touch

Question 18

action potential

Answer 18

also known as a nerve impulse
initiated when local graded potential is large enough to depolarize the cell membrane
rapid and long distance

Question 19

depolarization

Answer 19

signal that lessens the negativity inside a neuron

Question 20

hyperpolarization

Answer 20

signal that hightens the negativity inside a neuron

Question 21

neuronal signals rely on the cell’s ___

Answer 21

membrane potential

Question 22

threshold

Answer 22

voltage needed to depolarize a cell so to produce action (an action potential)

Question 23

all neurons have a resting potential and it is ___ in nature

Answer 23

negative

Question 24

Ex of graded local potential and action potential in retina

Answer 24

light creates a local graded potential in photoreceptors which then creates a local graded potential in bipolar cells which then creates a local graded potential in ganglion cells which then creates an action potential in the ganglion cells to conduct that signal to higher centers which will convert that information into new perceptive information

Question 25

resting potential

Answer 25

the potential difference of mV between the inside and outside of a cell
the inside of the cell is negative at resting potential
(-)70 mV