Kap 5. Methods and strategies Flashcards
Experimental ablation
is an reseach method used to investigate brain functions. It involves removing or inactivating part of the brain and evaluating an animal´s subsequent behavior
- removing brain tissue, or damaging the tissue to disrupt its functions
- it is one of the oldest methods used in neuroscience
lesion studies / method
patients with brain damage are examined to determine which brain structures are damaged and how this influences the patient’s behavior
Goal = understand what functions are perfomed by different regions in the brain and how this influences behavior
Some of the oldest and most famous studies in neuroscience are lesion studies.
Lesion
wound / injury
Brain lesion
a reaschers who destroy part of the brain, refers to the damage as a “ brain lesion”
“damage of the brain”
sham lesion
the name given to a control procedure during a lesion experiment
(placebo)
Exitotoxic lesions
lesions produces Excitotoxic lesions are permanent lesions that have been created through the injection of a neurotoxin, whichs kills neurons by stimulating them to death
Stereotaxic surgery
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To target a specific brain region, stereotaxic surgery is used.
A stereotaxic brain atlas is used to find the coordinates required.
Use a grid system to pinpoint exact regions in a repeatable way.
Stereotaxic atlas
a book contains images that correspond to frontal sections of the brain taken at various distances rostral and caudal to bregma
Fontanelle
is a soft spot at the junction of the coronal and sagittal sutures of the head of babies
Bregma
Once the gap cloces in the fontanelle, it is called bregma “front of head”
Stereotaxic apparatus
is a device that includes a head holder, which maintains the skull in the proper orientation
- f.eks brukt på brainsurgery on rats
Autolytic
self-dissolving
Anterograde means …
moving forward
Anterograde labeling method
employ chemicals that are taken up by dendrites or cell bodies and are then transported through the axons toward the terminal buttons.
Immunocytochemical method
take advantage of an immune reaction
Antigens
proteins/peptides found on the surface of bacteria or viruses
Antibodies
proteins produced by white blood cells to destroy invading microorganisms
- either secreted by white blood cells, or located on their surface in the way neurotransmitter receptors are located on the surface of neurons
VMH
ventromedial nucleus of the hypothalamus
Retrograde means
moving backwards
Retrograde labeling methods
employ chemicals that are taken up by teminal buttons and carried backward through the axons toward the cell bodies
CT
computerized tomography
X - ray donutshaped ring tube
uses X-rays to image “slices” through the brain (or other tissues)
MRI
Magnetic resonance imaging
- uses a strong magnetic field to image the brain; better resolution than CT scans
DTI
Diffusion tensor imaging
– uses an MRI scanner to identify bundles of axons so connections between brain regions can be studied.
- takes advantage of the fact that the mocement of water molecules in budles of white matter will not be random but will tend to be in a direction parallell to the axons that make up the bundles
Retrograde tracing
Retrograde tracing involves putting a tracer where the axon terminals are which will travel backward along the axons to the cell bodies.