A Coggle Diagram about Imaging techniques (EEG, Computerized Tomography (CT): Uses movable Xray tube rotated along the patients head. Gathers intensity information from multiple angles. Data is entered into a matrix and calculations of brain radiodensity is calculated. This isformation is used to create a 3D model of the head. It can also generate "slices". Faster and cheaper than MRI. , Magnetic Resonance Imaging (MRI): When a person is in the MRI machine the protons of hydrogen atoms align with the magnetism from the machine.
Perturbations of this alignment creates information that can be measured and analyzed to create an image.
Resonance means the ability of a system to absorb energy delivered at a particular frequency; so protons in a strong magnetic field absorbs energy when energy is delivered at a specific resonant frequency.
The atoms get "excited" when the MRI releases energy as radio waves at the resonant frequency of protons, and when the waves from the MRI are turned off the protons begin to release the energy they absorbed, called MR signals, which gets measured. Image that shows proton density and distribution of other tissue characteristics .
These characteristics are different for the kinds of matter in the brain, you get a lot of neuroanatomical detail.
Most MRI provide a structural resolution of ca. 1 mm or less. This depends on the strength of the magnetic field, the kind of images being collected and the strength of the gradient coils (what causes the local magnetic field to differ in strength along specific directions, and enables us to create an image of the signals).
MRI are good because: they are non-invasive, creates high resolution images, and due to the ability to vary the gradient and radio-frequency pulse parameters we can get images sensitive to different aspects of brain structure , DTI:check:
Macroscopic MRI (diffusion weighted imaging): Delineating the white matter fiber tracts of the brain.
Water molecules in the body and brain are always moving a little within their area, and this diffusion affects the MR signal. Because the water molecules' environment vary in the brain, so does their diffusion, and with these particularly sensitive MR signals we can create diffusion weighted images that reflects diffusion characteristics across the brain
DTI quantifies the relative diffusivity of water in each voxel into directional components. Water tends to diffuse more across fiber tracts, (myelinated axons), meaning that white matter has more anisotrophy (meaning that the diffusion tends to have a perferred direction) where diffusion in other brain regions tends to be more isotropic, meaning no perferred direction). , ERPs (event-related potentials)
more effective way of relating scalp electrical activity to cognitive functions.
Small voltage fluctuations in an ongoing EEG triggered by sensory/cognitive events; neural activity in response to these events.
High temporal resolution of neural processing (respons) and MEG (magnetoencephalography)), Basics (Seven themes of cognition) and Measurement (RT)