Neuroimaging

Neuroimaging

(description, uses, strengths, limitations)

• Electroencephalogram (EEG)

  • Records movement of electricity across the scalp to indicate neuronalactivity

    • Electrons pick up and record electrical activity in the brain

  • Measures brain frequency (brainwaves per second)

  • Measures brain wave amplitude

    • higher amplitude = stronger signal

  • Uses:

    • Detect and investigate epilepsy

    • Investigate states of consciousness

    • Diagnosing abnormalities

      → Deafness

      → Visual issues in infants

  • Advantages:

    • Cheap

    • Good temporal resolution

    • No radiation

    • Non invasive

    • Easily transportable

  • Disadvantages:

    • Does not indicate why a problem is occurring

    • Needs lots of interpretation

      • Background

      • Artifacts

Still images: shows structure of the nervous system

• Diagnose abnormalities (physical)

Dynamic images: shows function of the nervous system

• Diagnose functional diseases

• Computed Axial Tomography (CT)

  • Still imaging

  • Multiple x-rays taken

  • Computer uses images to create cross-sectional picture of brain

  • Uses:

    Detect:

    • Tumors

    • Strokes

    • Abnormalities in brain structure

  • Advantages:

    • Shows extent of a lesion

    • Quicker than MRI

  • Disadvantages:

    • Higher levels of radiation

      = ^ risk of cancer

• Magnetic Resonance Imaging (MRI)

  • Still imaging

  • Uses strong magnetic field, radio-frequency pulses and computers to produce 3D images

  • Uses:

    Detect:

    • Tumors

    • Other abnormalities

  • Advantages:

    • No ionising radiation

    • Excellent spatial resolution

  • Disadvantages:

    • Strong magnetic field

    • High cost

• Functional Magnetic Resonance Imaging (fMRI)

  • Dynamic imaging

  • Used to measure activity in brain when neurons are consuming oxygen

  • Uses:

    • Enables observation and measurement of changes in the brain during activity

  • Advantages:

    • No ionising radiation

    • Enables observation and measurement of changes in the brain during activity

  • Disadvantages:

    • Strong magnetic field