Flashcards in 1 - History of Neuroscience Deck (22):
What is the brief history of neuroscience?
Ancient Egypt: viewed brain as not important and threw it out during mummification.
Ancient Greece: brain important in intelligence/sensation/mental processes, until Aristotle who thought the heart was base for intelligence and emotions.
Ancient Rome: Dissections in monkeys, associated whole brain with psychological functions.
Renaissance: Da Vinci: worked out shape of ventricles, Vesailus; importance of ventricles
What was the Ancient Egyptians view of neuroscience?
- Brain wasn't that important and threw it out during mummification.
- Knew brain damage led to changes in some abilities
What was the Ancient Greek view of neuroscience?
- Brain was important for intelligence, sensation and mental processes.
- Aristotle, believed the heart was the source of intelligence and emotions.
- Heophilus of Chalcedon distinguished the cerebrum and cerebellum and described the ventricles.
What was the Ancient Roman view of neuroscience?
- Galen: great surgeon in Roman Empire
- Looked at brain injuries of gladiators and noticed behavioural changes.
- Dissections in monkeys.
- Believed in psychic pneuma: fluid which passed along nerves to all parts of the body and caused contractions (first concept of neural communication).
- Associated the whole brain with psychological functions, but higher mental functions was due to ventricles.
What is the Psychic pneuma
First concept of neural communication developed by Galen.
Fluid which passed along nerves to all parts of the body causing muscle contractions
Where did Galen believe higher mental processes occured in the brain?
The whole brain was associated with psychological functions, but higher mental processes due to the ventricles.
What did Vesalius do and believe during the Renaissance?
Produced very details anatomical drawings.
Believed nerves transmit sensation and motion and viewed the ventricles as very important.
Descartes had a philosophical approach to neuroscience, what was it?
Dualism; body and soul are separate.
Believed animal spirits were made up of small particles and flowed from the brain throughout the body to make it move.
Soul was the "mind" and they communicated with the body through the pinneal gland.
What did Galvani add to neuroscience understanding?
Electric, rather than hydraulic, transmission in nerves. Through studies with frogs.
What did Golgi add to neuroscience understanding?
Silver nitrate staining method
Enabled visualization of nerve cell body, and could then tell the brain was made up of individual cells.
Wgat did Ramon y Cajal add to neuroscience understanding?
Interpreted Golgi's findings and provided evidence of individual neurons.
Classified different types of neurons and glia and hypothesized neurons grow and change
What is the neuron doctrine (Golgi & Ramon y Cajal)?
- Neurons are anatomically discrete, autonomous cells that can interact.
- Synapses are gaps that separate neurons.
- Information is transmitted in one direction, from dendrite to axon.
All this information was possible from staining tissue (Nobel Prize for GRyC)
What is phrenology ?
The study of the shape and size of the skull which indicates personality
Gall believed in this.
What did Flourens find disproving phrenology?
Experimentally investigated Gal's claims.
Localised ablation of tissue of living animals.
-Hemispheres; perception, movement
- Cerebellum; balance, co-ordination
- Brainstem; breathing and death
Holistic functioning for memory and cognition
What was Broca's experimental findings and conclusions about the localisation of language in the brain?
- Had a patient with R hemiplegia and couldn't speak or write.
- Could understand speech but could only say "tan"
- Post-mortem; stroke involved part of insula and frontal lobe.
- he had a few more cases with similar lesions.
- the seat of language was in the inferior posterior portion of frontal lobe.
- two sides of the brain controlled opposite sides of the body.
Where did Broca say the seat of language was?
Inferior posterior portion of frontal lobe.
What did Phineas Gage's accident suggest about the localisation of personality in the brain?
- construction on railway, explosion put a tamping iron through his cheek and exited through the top of his head.
- Was conscious, and not paralyzed and lost no dexterity in his hands.
- Pervasive and substantial personality change. Especially with social and ethical behaviour and decision making.
Holistic view of personality
What did Lashley find out about engrams (permanent change due to memories)?
- Induced localized, surgical damage in animals, looking at effects of maze learning.
- Found no specific site
- Extent of lesion mattered; mass action
When did neuroscience make a swing back to a more localised view?
Mid 20th Century due to the Surgical Ablation
What did the surgical ablation of the 20th century demonstrate?
1950s: growth of frontal lobotomy.
- Disruption of the white matter of frontal lobes.
- Resulted in "frontal lobe syndrome"
1950s: epilepsy surgery
- brain regions associated with cognitive functions disrupted by cortical stimulation with electrical current, or permanent removal of tissue.
What is the "frontal lobe syndrome?"
Reduced ability to formulate adequate plans
Lessened ability to modify behaviour in response to feedback about a goal.