Neuroscience test 1- OG questions

• Electrodes are placed on the scalp and they measure the AP of the neurons directly beneath them
• Limited to the cortex
• Temporal resolution is in real time

Static- visual picture of structural tissue

Functioning- looks at function of the tissue

• like an x-ray but the image is in 3D, camera goes all the way around body and takes images then pieces them together 
• spatial resolution is 1cm
• temporal resolution is real time

• The MRI machine has 1.5-3 T magnets inside that rotate. The magnetic field spins protons on their axis and a radio frequency interrupts them 90 degrees away from their original axis. The amount of time it takes for the protons to return to their original axis 
• Spatial resolution is 1 mm 
• Temporal resolution is a few minutes

• PET scans- 
• measures glucose levels in the brain 
• has lower spatial resolution/ temporal resolution
• Invasive method, requires injection of radioactive material 

• fMRI- 
• measures oxygen levels in the brain. 
• Higher spatial resolution/ temporal resolution
• Noninvasive but more expensive

• Measures glucose levels in the brain 
• Patients are injected with glucose with radioactive tags 
• Imaging detects the brain regions that are using the most glucose 
• Spatial resolution- 10mm.
• Temporal resolution- 30 secs

• Measures oxygen levels in the blood. Uses BOLD symbol to find hemoglobin and detect if the Fe ions have bonded with O2 or not
• Spatial resolution- 1mm
• Temporal resolution- 5 secs

Event related potential

Using a stereotaxic frame, the doctor can align the needle with the part of the brain that he wants to see and then lowers the needle through the skull and into the brain. It stays outside the electron and uses an electrode in the tip to measure AP

• A magnetic field is induced over the cranium which causes the neurons to fire randomly. The neurons are more active than normal but because they have been interrupted they fire randomly and cannot function in an organized manner
• Spatial- 1-5 cm
• Temporal- microseconds

• Transection- cutting 
• Aspiration- vacuuming

Measures brain activity by recording the AP of many neurons at once

When during imaging the patients brain is first recorded at baseline and then during the stimulus so the researchers know what is due to manipulation and what is due to normal activity