FMRI

• measures blood flow in the brain when a person performs a particular task, neurons in the brain that are most active use most energy
• energy requires both glucose and oxygen
• oxygen is released for use by these active neurons at which point the haemoglobin (which carries the oxygen) becomes deoxygenated.
• deoxygenated haemoglobin has a different magnetic quality from oxygenated haemoglobin. An fMRI can detect these diff magnetic qualities to create a dynamic 3D map of the brain
• temporal resolution- fmri images show activity approximately 1-4 seconds after it occurs
• spatial resolution- fmri images are thought to be accurate within 1-2 mm
• measures blood flow in task performance,
• FMRI measures blood flow when a person performs a task, Nuerons in the brain that are most active use most energy, energy requires glucose and oxygen
• deoxygenated haemoglobin has a different magnetic quality from oxygenated haemoglobin, an fMRI can detect these different magnetic qualities to create a dynamic (moving) 3D map of the brain
• temporal resolution- fMRI images show activity approx 1-4 seconds after occurance
• spatial resolution- fMRI images are thought to be accurate between 1-2 mm
• functional magnetic resonance imaging- FMRI detects blood flow in the brain, as more areas of the brain need more blood (containing oxygenated hemoglobin with distinct magnetic properties), these active areas can be compared to low activation areas with a lower blood supply and displayed on an FMRI image,
• evaluations- good spatial resolution of 1mm, preciseley identifying active brain regions and patterns of activation over time while participants complete experimental conditions
• FMRI is a non-invasive and safe technique for experiments compared to options that use radiation like PET scanners
• a criticism of FMRI- poor temporal resolution as one image is taken every few seconds and delay in blood flow after activity. many brain processes are too fast to study
• Another criticism of FMRI- FMRI machines are expensive to build and operate, also as the participant needs to be still, experiments with body movement are not possible,
• poor temporal resolution- a 5 second time lag between the movement of activity and the image showing on the screen
• risk free and objective- risk free as no radiation is involved
• FMRI research is expensive leading to reduced sample sizes which negatively impact the validity of the research
• FMRI uses large magnets to detect blood flow in the brain,