Neurobiology of Consciousness Homework 1

Problem 1

Consider a spinal lower motor neuron that receives excitatory input from a sensory neuron and inhibitory input coming from the motor cortex. Describe the electrical phenomena one can record from the cell body of the spinal lower motor neuron. Discuss the role of the spinal lower motor neuron as an integrator electrical potentials.

Problem 2

Please take a look at the electron micrograph of a this synapse between two neurons.
-Mark the presynaptic neuron and the postsynaptic neuron on the micrograph /

Problem 3

What events do normally trigger an action potential in a neuron?

Problem 4

List the reasons for a neuron to use myelin wrapped around its axon?

Problem 5

How do neurons usually encode the intensity of a stimulus?

Problem 6

How many synapses does a normal neuron have: one, two, hundreds, thousands, millions?

Problem 7

Describe several mechanisms for regulation of connection strength between two neurons in the human brain.

Problem 8

How neurons (and skeletal muscles) are different from other cells in the body?

Problem 9

_____ have a branched structure and receive stimulation from other neurons.
A) Axons
B) Dendrites
C) Glial cells
D) Soma
Problem 10
The part of a neuron that transmits information over long distances is the:
A) Soma
B) Axon
C) Dendrite
D) Synapse
Problem 11
Sensory neurons:
A) Control muscles and produce movement
B) Send messages away from the brain toward the periphery
C) Gather information from the environment and convey it into the central nervous system
D) Have cell bodies covered with myelin
E) All of the above
Problem 12
When a neuron is at rest, the inside of the neuron:
A) Is negatively charged with respect to the outside
B) Is positively charged with respect to the outside
C) Is not charged
D) Converts potential energy into chemical energy

Problem 13

Action Potential is amplified everywhere EXCEPT:

A. axon hillock
B. nodes of Ranvier

C. internodal space (the space between nodes of Ranvier)

Problem 14

Form a hypothesis of human evolution and origin of language – do not do research: What makes modern humans so much different from other animals?

Problem 15

Form a hypothesis of human evolution and origin of language – do not do research: What caused the dramatic and abrupt change of human behavior 100,000 years ago, often called the “Great leap forward?”

Problem 16

Form a hypothesis of human evolution and origin of language – do not do research: What was the origin of language? and what is language in the first place? Is it just an ability to produce many words (aka articulate speech)? or is it something else?

Questions based on the Ian Tattersall article:

What are the two groups of humans that are often compared in the article?

What is Ian’s argument against the mutation theory (page 59)

Consider Ian’s definition of “Symbolic processes” (page 60, bottom left):

WHEN WE SPEAK OF “symbolic processes” in the brain or in the mind, we are referring to our ability to abstract elements of our experience and to represent them with discrete mental symbols. Other species certainly possess consciousness in some sense, but as far as we know, they live in the world simply as it presents itself to them. Presumably, for them the environment seems very much like a continuum, rather than a place, like ours, that is divided into the huge number of separate elements to which we humans give individual names. By separating out its elements in this way, human beings are able constantly to re-create the world, and individual aspects of it, in their minds. And what makes this possible is the ability to form and to manipulate mental symbols that correspond to elements we perceive in the world within and beyond ourselves. Members of other species often display high levels of intuitive reasoning, reacting to stimuli from the environment in quite complex ways, but only human beings are able arbitrarily to combine and recombine mental symbols and to ask themselves questions such as “What if?” And it is the ability to do this, above everything else, that forms the foundation of our vaunted creativity.

For this and the next question concerning definitions, I guess we can paraphrase Theodosius Dobzhansky’s - “Nothing in Biology Makes Sense Except in the Light of Evolution” into Nothing in Psychology is unambiguous except when described in the terms of Neurobiology. Can you translate the definition of “Symbolic processes” into clearer, less confusing terms?

When Ian is discussing Language, what exactly he is talking about?

Ian writes about Neanderthals “Could they talk” and then he equated talking and explanations that require generation of novel images on the part of a listener (page 60 bottom). Is it always the case? Can you come up with an example of talking that does not require generation of novel images on the part of a listener?

Can there be talking without syntax? Can you write a dialog void of syntax?