From past to future: how did neuroscience begin and where is it taking us? Flashcards
What is the basic definition of neuroscience?
& the object of it?
the study of the brain and the nervous system in health and disease
with the object of understanding the functions of the nervous system at many levels of analysis (molecular, cellular, synaptic, network, computational and behavioural approaches).
What is trepanation? & what is the modern version used for?
Also explain the cult following
Pre historic brain surgery
Trepanation is thought to have been an early conceptualisation for a disease or mental illness.
A modern version of this technique is used to release pressure when there is intracranial swelling.
There is a modern cult following of trepanation, whose purpose is to achieve higher levels of consciousness, although some argue it is just a new form of self-harm
Explain the Edwin Smith surgical papyrus?
oldest known medical writing in history
featured many sophisticated observations about the brain and its connections
What were the Greek contributions to medicine? & what was the key advice given?
Greek medicine moved towards observation and logical reasoning.
changes in diet, beneficial drugs and keeping the body in balance.
What was the humoral theory of health, include the 4 fluids?
blood, phlegm, yellow bile and black bile
- needed to be kept in balance for wellness. Illness was supposedly caused when these fluids became out of balance, and sometimes required an intervention in order to set things righ
Rene descartes
What is the concept of dualism?
the brain and the body are mechanical things but the mind is not physical and, therefore, not subject to scientific observation.
This influenced our thinking on animals, leading to several experiments being carried out, which led to much of the understanding in neuroscience we have today.
What is the concept of monism?
the mind is a product of physical neural activity.
In 1664, Thomas Willis publishes The Anatomy of the Brain, the first book really dedicated to the study of the brain.
What does it describe? & what term is used for the first time?
It described reflexes, epilepsy, apoplexy and paralysis, and for the very first time, the term ‘neurology’ is used.
Who was the father of microscopy?
Anton van Leeuwenhoek
(1632-1723)
Created the very first microscope in 1674.
Who established electricity as the mode of communication used by the nervous system?
Luigi Galvani
Mary Shelly, using the idea that electricity could reanimate dead tissue, she wrote what?
Frankenstein
What is the Bell Magendie Law?
representation of division of labour within the brain.
first time it was figured out that information travels in 1 direction, not 2 along motor and sensory nerves
Charles Darwin and Russell Wallace created new concepts of what?
• evolution
• common traits between humans and
animals (such as the brain)
What is the ‘Science of phrenology’?
non-invasive attempt that observes the structure (observable bumps) of a person’s skull, and then correlate them with all sorts of personality characteristics and abilities
- incorrect however very popular at the time (in the 1970s)
What did phrenology, although incorrect pave the way for?
Localisation of function
What neuroimaging technique was thought to be compared to phrenology?
fMRI
What was Paul Broca’s influence?
Used clinical observation with autopsy to study the correlation between brain damage and behaviour deficits.
What is the Broca’s area linked to?
linked to speech production and language functions
What did Gustav Fritsch and Eduard Hitzig accomplish regarding in vivo experimentation on animals?
Used in vivo experimentation on animals to demonstrate the localisation of motor function and the property of contralateral control when stimulating the motor cortex.
Explain the neuron doctrine with regards to Camillo Golgi and Santiago Ramón y Cajal? and why they disagreed with each other?
Golgi believed that the nervous system was neural net, a vast network of continuous fibres.
Cajal argued that the nervous system was an array of discrete independent cells, now known as the neuron doctrine:
a brain made of independent cells that talk to one another
- Golgi created Golgi stain
- Cajal, in turn, used the Golgi stain to prove his theory of individual cells.
Explain Otto Loewi’s Vagusstoff experiment in 1921 (chemical transmission)?
and what was the chemical used to prove this?
This was the first piece of evidence to show the
importance of chemicals in neural transmission which, along with the critical element of electricity, leading us to say that neurons are electrochemical in nature.
chemical used is acetylcholine
Who coined the word synapse?
Charles Sherrington
TOPIC 2: NEURAL STEM CELLS
What is the definition of neural stem cells?
Undifferentiated cells, defined by their capacity for self-renewal and multipotency
During central nervous system development, neural stem cells proliferate and divide to generate clonally related progeny that differentiate into what?
neurons, astrocytes and oligodendrocytes
Symmetric division of neural stem cells include?
• ability to self-renew
• maintains neural stem
cell (NSC) population
Asymmetric division of neural stem cells include?
And what lineages are they restricted to?
- produces one NSC, and one neural progenitor cell (NPC)
* restricted to neuronal or glial lineages
what are the 3 types of stem cell potencies?
1.Totipotent
‘Toti’ = whole
Can give rise to any and all human cell types and to an entire functional organism Most versatile stem cell
- Pluripotent
“Pluri”= many
Can give rise to any and all human cell types
Day four of development: embryo forms into two layers, outer layer and inner mass. As pluripotent stem cells continue to divide, they begin to specialise further
- Mulitpotent
“multi”= several
Can give rise to a limited range of cells within a tissue type
The offspring of the pluripotent cells become the progenitors of such cell lines as blood cells, skin cells and nerve cells
What are examples of each?
totipotent: fertilised eggs (days 0-4)
Pluripotent: inner cell mass layer of the blastocyst stem cells
Multipotent: neural stem cells
Neural stem cells are the source of all neuron types in the central and peripheral nervous systems
True or False?
TRUE
Neural stem cells from the neural tube are commonly named neuroepithelial cells, which means what?
& in the cortex, neuroepithelial cells transition into what?
the most primitive form of neural stem cells.
- radial glial cells, also a form of neural stem cells.
How does the nervous system and neural stem cells begin forming? in 3 key areas
Primitive: CNS begins as a tube of neuroepithelia cells
In the cortex: Neuroepithelial cells transition into radial glial cells.
- this gives rise to neural progenitors, neurons, astrocytes and oligodendrocytes.
In the spinal cord and striatum: Radial glial cells are not as prominent. Progenitors emerge from nonradial multipotent NSC populations.
Once development has ended Neural stem cell populations are very rare.
True or false?
TRUE
What areas do the become restricted to once development has ended?
Neural stem cell populations are restricted to the dentate gyrus (DG) and the subventricular zone (SVZ).
IDENTIFICATION OF NEURAL STEM CELLS
To identify embryonic neural stem cells, it remains very controversial. There is a lack of very specific neural stem cell markers, which make it very difficult to demonstrate long-term self-renewal and multipotency in vivo.
true or false?
TRUE
How can the neural stem cells identity change?
The identity of NSCs could change spatially (neural tube position) and temporally (developmental age).
What genes are among the earliest genes expressed in the early neural plate?
Sox genes (eg. Sox2)
What 3 genes/proteins can be used as neural stem cell markers?
Sox2, nestin (intermediate filament protein) and mushashi (RNA-binding protein)
can only be expressed in restricted progenitors
No exclusive antigens have been identified for NSCs
true or false?
TRUE
Combinations of positive and negative markers are required to better identify NSCs
TRUE OR FALSE?
TRUE
One way to identify dividing cells, is to inject what?
bromodeoxyuridine or BrdU, which is an analogue of thymidine, that will intercalate in the DNA as it replicates
Quantitative: we can count the number of cells that have been dividing
Explain the Retroviral labelling technique for dividing cells?
Is this quantitative or qualitative?
- retrovirus engineered to express GFP
- injected locally in the hippocampus
Qualitative: injected locally so we are not labelling the entire structure.