Chapter 7 - Studying the Brain Flashcards
1
Q
What was the silver lining of the “frozen” addicts case during the 70s?
A
- Development for animal models of Parkinson disease for study
- Barry Kidston accidentally synthesized MPTP but wanted MPPP
- This isomer broke down into MPP+ which is toxic
- Ended up killing a bunch of dopaminergic neurons in the substantia nigra
2
Q
What’s histology?
A
- Branch of biology which studies the microscopic anatomy of biological tissues
3
Q
What was learned during the contextual learning rat study?
A
- Discovered that the dentate gyrus neurons are necessary for contextual learning
4
Q
What were the Morris swimming tasks?
A
- Rats must navigate a swimming pool to find hidden platform
- There were different variations to test specific types of spatial memory: (a) place learning task (b) matching-to-place task (c) landmark learning task
5
Q
What was the purpose of the skilled reaching task?
A
- Wanted to assess deficits and recovery in animal models of stroke
- Rats ability to reach into slot and retrieve food
- Researchers would break down their movements and score them
6
Q
What’s a stereotaxic apparatus?
A
- A surgical instrument permitting researchers/neurosurgeons to target a specific area of the brain
- Head is held in a fixed position, allowing for precise positioning of all brain regions relative to each other.
7
Q
What was informative about Phineas Gage’s experience?
A
- Provided insight into the functions of the frontal lobe
8
Q
Who was the first to use electrical stimulation to the brain?
A
- Canadian neurosurgeon Wilder Penfield during the 1950s
- Did it first on the cerebral cortex of humans with untreatable epilepsy
- Done on live patients cause brain has no pain receptors
- Able to do some brain mapping
9
Q
What’s deep brain stimulation? Advantages/disadvantages?
A
- Electrodes implanted deep in brain to stimulate a targeted area with a low-voltage electrical current to facilitate behaviour
- Used for PD, depression, schizophrenia, OCD, epilepsy Etc.
- Disadvantages: May damage other tissues, and electrodes heat up
10
Q
What’s transcranial magnetic stimulation (TMS)? Advantages/disadvantages?
A
- Advantages: Non-invasive, not super expensive
- Disadvantages: Doesn’t penetrate super deep
- Magnetic coil is placed over the skull to stimulate the underlying brain
- Used either to induce behaviour or to disrupt ongoing behaviour
- Magnetic field lines pull on ions and induce a current in the brain
11
Q
What are the advantages/disadvantages of using drugs as a form of brain stimulation?
A
- Disadvantages: Must either pass through BBB or be administered through an indwelling cannula; poor temporal resolution
- Advantages: Can influence activity of specific neurons. Because drugs wear off over time, can study drug effects on learned behaviours (animal is its own control)
12
Q
What effects do the drugs haloperidol and amphetamine have on rats?
A
- Haloperidol = reduce dopaminergic neuron functioning
- Amphetamine = increases dopamine activity
13
Q
Genetic knock-outs vs. knock-ins?
A
- Knock-outs = loss of function via gene deletion or inactivation
- Knock-ins = gain of function via inserting or activating a gene
14
Q
What’s CRISPR-Cas9?
A
- Bacterial defence mechanism for fending off viruses
- Acts as an all-purpose tool for cutting DNA in any cell
- Can be used for both gene inactivation and insertions, or to repair a mutated gene
- Cas9 is the protein that acts as a nuclease (enzyme that cuts DNA)
- Start with a strand of RNA that is complimentary to the gene of interest
15
Q
What is optogenetics?
A
- Transgenic technique that combines genetics and light to control targeted cells in living tissues
- Works by expressing light-sensitive ion channels or pumps in specific target cells
- Selected neurons respond immediately when exposed to light
