6. BIOPSYCHOLOGY (WAYS OF STUDYING THE BRAIN: FUNCTIONAL MAGNETIC RESONANCE IMAGING (FMRI); ELECTROENCEPHALOGRAM AND EVENT RELATED POTENTIALS (ERPS); POST-MORTEM EXAMINATIONS) Flashcards
What does fMRI measure and how does it work?
fMRI measures changes in brain activity by detecting changes in blood flow to areas of the brain. When a brain region becomes more active, it requires more oxygen, and blood flow increases to deliver oxygenated blood, which can be measured to identify active areas during specific tasks.
What is the spatial and temporal resolution of fMRI?
fMRI has a high spatial resolution of 1-2 mm, allowing accurate identification of brain regions. However, it has relatively poor temporal resolution (1-4 seconds), which means it cannot track rapid changes in brain activity as precisely as other methods like EEG.
What is an advantage of using fMRI?
fMRI is non-invasive and does not involve radiation, making it virtually risk-free for participants, allowing for broader use in brain research.
What is a limitation of fMRI?
fMRI does not establish cause-and-effect relationships as it only measures changes in blood flow, not direct neural activity. This makes it difficult to draw definitive conclusions about brain function.
How does EEG work?
An EEG records electrical activity in the brain by placing electrodes on the scalp to detect small electrical charges generated by brain cells. These signals are graphed to create an EEG that reflects the brain’s activity over time.
What is the temporal and spatial resolution of EEG?
EEG has very high temporal resolution (1-10 milliseconds), making it excellent for measuring real-time brain activity. However, it has limited spatial resolution, only providing general information about the activity in superficial brain regions.
What is an advantage of EEG?
EEG is non-invasive and provides high temporal resolution, which allows researchers to observe brain activity in real-time, providing valuable insights into processes like epilepsy and other brain disorders.
What is a limitation of EEG?
EEG has limited spatial resolution, making it difficult to pinpoint the exact location of activity in the brain. It only provides information on general regions, unlike fMRI, which can provide more detailed location-based data.
What are Event-Related Potentials (ERPs)?
ERPs are measured using the same equipment as EEGs and refer to brain activity in response to a specific stimulus. They are obtained by averaging EEG recordings from multiple stimulus presentations, helping isolate the brain’s response to a particular event.
What is a strength of using ERPs?
ERPs can establish cause-and-effect relationships because they allow researchers to isolate specific brain responses to stimuli. This provides more accurate conclusions about the brain’s activity in response to experimental manipulations.
What is a limitation of using ERPs?
ERPs have limited spatial resolution, meaning they can only pinpoint general regions of brain activity, making it difficult to determine exactly where in the brain a specific response occurs.
What is a post-mortem examination in brain research?
A post-mortem examination involves studying a person’s brain after death to look for structural or neurochemical abnormalities, especially in cases of rare disorders or unusual mental deficits during the person’s lifetime.
What is the advantage of post-mortem examinations?
Post-mortem allows for a detailed examination of the brain’s anatomy and neurochemistry, which is not possible with live participants. It can provide insights into deep brain structures like the hippocampus and hypothalamus.
What is a limitation of post-mortem examinations?
Post-mortem examinations do not establish cause-and-effect relationships because it is difficult to link observed brain damage to the specific mental deficits exhibited during the person’s lifetime. Additionally, the sample size is usually small due to ethical and practical considerations.
What is the spatial and temporal resolution of post-mortem examinations?
Post-mortem examinations do not provide temporal or spatial resolution because they are conducted after death, and neuronal changes can occur post-mortem, potentially affecting the validity of the findings.
