Biopsychology Methods Flashcards
What is spatial resolution?
How fine in space we can measure
What is temporal resolution?
When in time did the change occur
What is a neural stain?
Stain some tissue components but not others
Selective process
How do we prepare brain tissue?
Perfusion -remove blood Hardening Slicing Mounting
What is a Golgi stain?
Silver chromate strains neurons black but not all neurons pick up the strain
We can’t see intracellular details but we did get the first view of the synapse
What is a nissil stain?
Stain penetrates all cells
Stains ribosomes
First view of structures within the neuron
Uses cresyl violet to stain
Why do we trace neural pathways?
To identify pathways that connect structures
What is anterograde tracing?
Where do axons go?
Use autoradiography
What is autoradiography?
Amino acids with radioactive hydrogen isotopes are taken into cell bodies and incorporated into proteins
What is retrograde tracing?
Where do axons come from?
HRP is taken up by axon terminals and stains cell bodies black
What is in situ hybridization?
Peptides and proteins located by mRNA
Complementary sequence binds to mRNA creating hybrid RNA
Hybrid RNA is labelled to locate mRNA
How are small-molecule neurotransmitted located?
Probing for enzymes that synthesize
What is immunocytochemistry?
Antibodies specific to the protein of interest
Antibodies attach to proteins of interest and are labelled with radioactivity, substrate colour change, or dye
Analyze under a microscope
What is X-ray computed tomography (CT)
Computer-assisted X-ray
3D view of the brain
Composed of 8-9 horizontal cross-sections
Low-resolution image
Used to visualize structural abnormalities
How does PET imaging work?
Inject carotid artery with a positron-emitting radionuclide
Positrons interact with electrons to produce photons (gamma rays)
Scanner detected photons and maps how many gamma rays are coming from a particular region
What is Positron emission tomography (PET)?
Indirectly measures activity and distribution of other neurochemicals and proteins
Indicates areas of activity during a task
No structural information
What is magnetic resonance imaging (MRI)?
High spatial resolution
Horizontal, coronal, and sagittal planes
Expensive
How do MRIs work?
A strong magnetic field passed through the brain
What is functional MRI (fMRI)?
Uses MRI methods -functional -structural -non-invasive -3D images of activity over brain High spatial resolution Poor temporal resolution
What is the bold response?
Pictures do not reflect changes in activity but rather changes in BOLD signal
How does fMRI work?
Changes in Blood Oxygen Level Dependent (BOLD) signal
Correlates with neural activity and is not a direct measure of neural activity