CH 4 - Neurons and the Brain

Question 1

How many watts does the brain have?

Answer 1

13 watts

Question 2

Is the brain embodied?

Answer 2

Yes it is part of the body

Question 3

How many brain regions are there per hemisphere?

Answer 3

180

Question 4

How many neurons are there

Answer 4

86 Billion

Question 5

How many km of nerve fibers?

Answer 5

> 750.000 km

Question 6

How much does the brain weigh?

Answer 6

1.4 kg

Question 7

What is the nervous system?

Answer 7

An organized group of cells specialized for the conduction of electrochemical stimuli from sensory receptors through a network to the site at which a response occurs.

Question 8

Which two subsystems of the nervous system exist in vertebrates?

Answer 8

Central Nervous System (CNS)

Peripheral Nervous System (PNS)

Question 9

What does the CNS do?

Answer 9

central information processing system formed by the brain and the spinal cord. It collects and distributes data throughout the body.

Question 10

What does the PNS do?

Answer 10

transmits signals between sensory organs, muscles and internal organs and the CNS.

Question 11

Cerebrum

Answer 11

The cerebrum (Großhirn) is the largest and uppermost portion of the brain and accounts for sensory integration, voluntary motion and higher-level cognitive functions.

It is split into two hemispheres that are
connected by the corpus callosum (Balken).

The cerebral cortex (Großhirnrinde), also
called the gray matter (graue Substanz), is
the folded outer layer of the cerebrum that
is mainly comprised of cell bodies.

The inner part of the cerebrum, the white
matter (weiße Substanz), is a core of nerve
fibers that connect the cortical regions.

Question 12

By what are the two hemispheres of the brain connected by?

Answer 12

The corpus callosum

Question 13

Cerebral cortex

Answer 13

Cortex is Latin for “bark,” and describes the outer gray matter covering of the cerebrum. The cortex has a large surface area due to its folds, and comprises about half of the brain’s weight.

The right hemisphere controls the left side of the body, and the left half controls the right side of the body. The two halves communicate with one another through a large, C-shaped structure of white matter and nerve pathways called the corpus callosum. The corpus callosum is in the center of the cerebrum.

Question 14

Difference between white and grey matter

Answer 14

Gray and white matter are two different regions of the central nervous system. In the brain, gray matter refers to the darker, outer portion, while white matter describes the lighter, inner section underneath. The white matter is a core of nerve fibers that connect the cortical regions

Question 15

Three anatomical features of the surface of the cerebral cortex

Answer 15

It is covered with ridges (gyri) and folds (sulci). On each hemisphere two sulci divide the cerebral surface into a frontal, parietal, temporal and occipital lobe

Question 16

occipital lobe

Answer 16

The occipital lobes sit at the back of the head and are responsible for visual perception, including colour, form and motion

Question 17

draw the brain

Answer 17

draw

Question 18

What does the brainstem do?

Answer 18

Connects the cerebrum with the spinal cord

Question 19

Which sections is the brainstem divided into?

Answer 19

• Diencephalon
• Midbrain
• Pons
• Medulla Oblongata

Question 20

Which four sub-structures is the Diencephalon divided into?

Answer 20

• Epithalamus (production of melatonin)
• Thalamus (relay and distribution of sensory and motor signals to different regions of the cerebral cortex)
• Hypothalamus (control of autonomic functions like temperature and appetite, behavior and hormone production)
• Subthalamus

Question 21

What is the autonomic nervous system = peripheral nervous system?

Answer 21

responsible for homeostasis (self-regulation) and operates largely unconsciously.

Question 22

What are the two antagonist subsystems of the autonomic nervous system?

Answer 22

Sympathetic nervous system & parasympathetic nervous system

Question 23

What does the sympathetic nervous system do?

Answer 23

connection of the internal organs to the brain; preparation of the organism for stress (increase of heart rate, blood fow, sweating)

Question 24

What does the parasympatic nervous system do?

Answer 24

mainly cranial nerves (Hirnnerven) and lumbar (lenden) spinal nerves
- sets the body to resting state and increases digestive functions

Question 25

Is connectivity static and dynamic?

Answer 25

Yes. It is static in anatomical connectivity and dynamic in functional connectivity, dependent on the current cognitive task.

Question 26

What can brain networks (topology) be analyzed with?

Answer 26

Graph theory

Question 27

What are brain networks related to?

Answer 27

Integrated information theory (IIT) attempts to provide a framework capable of explaining why some physical systems (such as human brains) are conscious

Question 28

Is there cognition without the brain?

Answer 28

Yes (sort of). Jellyfish have a diffuse nervous system.

Then there is the endocrine system (Hormonsystem) that is also present in humans that is a regulatory system that works in parallel to the nervous system by secreting hormones.

Question 29

Mythos about the brain

Answer 29

Only ten percent of the brain are used
Every part of the brain is used but not all parts are used at once (which would result in epilepsy).

The brain does not produce new neurons in adults
In certain brain areas, new neurons are produced throughout life.

The size of the brain is related to intelligence The brains of elephants and whales are much larger than those of humans

Question 30

A mapping of the nervous system

What is cognition connected to?

Answer 30

• Brain
• Sensory Organs (perception)
• Spinal Cord and Muscles (action)

-> draw slide 21

Question 31

A mapping of the nervous system

Function of the brain

Answer 31

Cognition connects to anticipation.
Anticipation leads to assimilation.
Assimilation leads to adaptation.
Adaptation connects to cognition.

Question 32

assimilation

Answer 32

the process of taking in and fully understanding information or ideas

Question 33

How can the mapping between cognitive functions and brain regions (lobes) be determined?

Answer 33

With functional brain imaging

Question 34

Frontal lobe

Answer 34

short-term memory, action planning, movement control

Question 35

Parietal lobe

Answer 35

somatic sensation, body image (connection of senses to the extremities)

Question 36

occipital lobe

Answer 36

vision

Question 37

temporal lobe

Answer 37

hearing, learning, memory, emotion

Question 38

The neocortex in the cerebral cortex is the center of

Answer 38

higher cognitive functions and intelligence

Question 39

6 parts of the neocortex

Answer 39

Layer I: Molecular Layer
- Dendrites of the cells located in deeper layers and axons that travel through this layer in other areas of the cortex
Layer II: External Granular Cell Layer
- Small pyramidal-shaped cells. Projections to other cells within the same and to other cortical areas.
Layer III: External Pyramidal Cell Layer
- similar to II. Neurons located deeper in the layer and lager.
Layer IV: Internal Granule Cell Layer
- large number of small spherical neurons.
- main recipient of sensory input from the thalamus
Layer V: Internal Pyramidal Cell Layer
- pyramidal cells even larger than those in layer III.
- major output pathway of the cortex
Layer VI: Multiform Layer
- layer with heterogeneous neurons which blends into the white matter.

-> Draw picture

Question 40

What structure exists in the cortex in addition to the laminar structure?

Answer 40

Columns. Cortical Microcircuits.

Question 41

What is the minicolumn?

Answer 41

The most basic building block is the minicolumn. It consists out of 80-100 neurons.

Question 42

What are cortical columns comprised of?

Answer 42

Many minicolumns