Identified by two broad categories: structural and functional imaging. Structural imaging evolved from radiographic techniques for imaging the brain through non-invasive techniques such computerised axial tomography (CAT) to two-dimensional structural magnetic resonance imaging (sMRI). Functional imaging, which began with xenon gas inhalation, really started to develop with the discovery of radioligands that remained in the blood stream or entered the brain to bind to certain receptors, which gave rise to single photon emission computerised tomography (SPECT) and positron emission tomography (PET). A subsequent breakthrough came with the development of oxygen-15 labeled water (H215O or H20-15) imaging. H20-15 emits positrons and creates images based on regional blood flow within the brain. Since active neurons recruit a robust blood supply, H20-15 PET allowed regional maps of brain activity to be made during a variety of cognitive tasks. When it was discovered that blood flow changes could be measured by H20-15, functional magnetic resonance imaging (fMRI) appeared on the scene. Instead of radiation or X-rays, MRI uses variation in the signal produced by the body’s protons when it is placed in a strong magnetic field. Other imaging or brain mapping techniques include electroencephalography (EEG), magnetoencephalography (MEG) and optical imaging. The progress made by neuro-imaging in understanding how the brain functions has caught the attention of politicians who see it as instrument to be used in court cases deciding on the guilt of an accused. It has been incorporated in the legal systems of India, Italy and the US, and is now been considered for similar use in France. Despite the wealth of criticism leveled at polygraphic lie-detection, politicians are still looking for the cheap(er) ‘quick fix’ to reduce the costs of legal proceedings through a misguided belief that somehow neuro-imaging offers a window into ‘mind reading’.
See Attention deficit hyperactivity disorder (AHDH), Blood Oxygenation Level Dependent Contrast (BOLD signal), Cerebellum (development), Cerebellum (functions), Cognitive neuroscience, Diffusion anisotropy, Diffusion tensor imaging, Diffusion tensor magnetic resonance imaging, Electroencephalogram (EEG), Electromagnetic fields, Event-related brain potentials (ERPs), Functional imaging, Functional magnetic resonance imaging (fMRI), Human Connectome Project (HCP), Ligands, Magnetic resonance imaging (MRI), MRI morphometry, Motor inhibition, Neuroimaging studies, Neuronal migration disorders, Optical imaging, Proton, Structural imaging, Structural magnetic resonance imaging (sMRI)