neuroscience
study of the function & structures of the nervous system (brain, neurons, synapses, etc.)
behavioural neuroscience
relates to the observable actions of humans & animals (or artificial systems)
changes to our understanding of the brain are limited by. . .
- religious or moral views
- methodological limitations
- serendipity (reliance on chance discoveries)
- scientific conservatism
Hippocrates (Ancient Greece)
- considered father of modern medicine
- first to propose brain controls the body
- out brain is the command center of body (not heart)
- noted behavioural effects of brain damage
- observed anatomy through open wounds after traumatic head injury of soldiers & gladiators
Who formulated the mind-body problem?
- Rene Descartes, France
- was first to discuss interactions b/w mental & physical
- considered humans & animals like machines
- interested in involuntary reflexes & believed behaviour was driven
What about Luigi Galvani? (Italy) (frog man)
- first to suggest nerve signals are electrical (not fluid)
- rejected idea of animal spirits flowing through hollow nerves
- made a chance discovery that an electrical charge applied to a frog’s leg made the muscle contract
- suggested that nerves much be coated in fat to prevent electricity from leaking out
What about Franz Joseph Gall (Germany)?
- moving beyond mind & brain - first to propose idea of a modular brain
- was interested in relationship b/w brain & personality
- influenced by physiognomy
What is physiognomy?
art of ascribing personality characters to facial features
What did Franz Joseph Gall propose about the brain?
- proposed the brain is composed of several distinct “organs of thought” or faculties
- reflected by characteristic patterns of bumps on skull
- skull maps used to read person’s character
- this is known as PHRENOLOGY
What did Franz Joseph Gall (Germany) introduce?
the important notion of “cortical localisation of function”
- modular organisation
Who provided the first solid evidence of brain modularity?
Paul Broca (France)
- first described in patient Leborgne
- unable to speak after damage to left frontal lobe
- normal chewing & language comprehension
Broca’s aphasia
- autopsy used to figure it out
Carl Wernicke, Germany
-Wernicke’s area
- Unable to comprehend speech
- Normal hearing & language production
- Similar patients subsequently seen with
damage to posterior part of the superior gyrus
How much does adult brain weigh?
1400 g - it is 3% of body weight
How many neurons in adult brain?
100 billion neurons
1,000,000 billion synapses
10^1000000 possible circuits
How much of the energy resources of body does the brain consume?
20%
Is also remarkably energy
efficient running on
20Watts (equivalent to
simple light globe)
Neuropsychology is. . . ?
- Research and clinical speciality
- links brain damage (lesions) with psychological
processes - assess risk (before surgery),
- assess impairments and improvements (after
damage) - behavioural and neuroimaging measures
What is psychopharmacology?
looks at - the role of neurochemistry in mind and behaviour
- natural = neurotransmitters & Hormones
- artificial = drugs
more neurons in the brain =
more synaptic connections = more complexity of brain
The Allen Brain Institute
- 100 million donation from Microsoft founder Paul Allen
- Creating very detailed maps/atlas with data from mouse & human brain from brain areas > neurons>genes
The Human Brain Project
- EU 10-year initiative worth over $1 Billion
- emphasis on simulating neurons for brain inspired computing, neuromorphic computing
What does the human brain project state?
- HBP seeks to bring the bring vital software tools to neuroscience to:
- reduce the need for animal experiments
- study diseases in unprecedented in silico experiments
- improve the validation of data and experiments with computational validation
What does the virtual brain do?
Simulates/models whole brain dynamics and
functional connectivity to understand global brain function in healthy and disordered states like epilepsy
Main 2 divisions of nervous system
peripheral nervous system (PNS)
central nervous system (CNS)
PNS
cranial & spinal nerves
