Neuropsychology

Animal work often involves vivisection and is particularly controversial both from the moral angle (see animal rights) and from the scientific angle, with some scientists skeptical of the claims that findings from animal neuropsychology can be extrapolated to humans while others claim such work is essential to understand neural systems and related medical problems.

Clinical neuropsychology is the application of neuropsychological knowledge to the assessment (see neuropsychological test), management and rehabilitation of people who have suffered illness or injury (particularly to the brain) which has caused neurocognitive problems. In particular they bring a psychological viewpoint to treatment, to understand how such illness and injury may affect, and be affected by psychological factors. Clinical neuropsychologists typically work in hospital settings in an interdisciplinary medical team, although private practice work is not unknown.

Cognitive neuropsychology is a relatively new development and has emerged as a distillation of the complimentary approaches of both experimental and clinical neuropsychology. It seeks to understand the mind and brain by studying people who have suffered brain injury or neurological illness. This is based on the principle that if a specific cognitive problem can be found after an injury to a specific area of the brain, it is likely that this part of the brain is in some way involved. A more recent but related approach is cognitive neuropsychiatry which seeks to understand the normal function of mind and brain by studying psychiatric or mental illness.

Connectionism is the use of artificial neural networks to model specific cognitive processes using what are considered to be simplified but plausible models of how neurons operate. Once trained to perform a specific cognitive task these networks are often damaged or 'lesioned' to simulate brain injury or impairment in an attempt to understand and compare the results to the effects of brain injury in humans.

Functional neuroimaging uses specific brain imaging technologies to take readings from the brain, usually when a person is doing a particular task, in an attempt to understand how the activation of particular brain areas is related to the task.

In practice these approaches are not mutually exclusive and most neuropsychologists select the best approach or approaches for the task to be completed.

• The use of standardised neuropsychological tests. These are often simple paper and pencil tasks but they have been designed and tested so the performance on the task can be linked to specific neurocognitive processes.

• The use of 'brain scanners' to investigate the structure or function of the brain is common, either as simply a way of better assessing brain injury with high resolution pictures, or by examining the relative activations of different brain areas. Such technologies may include fMRI (functional Magnetic Resonance Imaging), PET (Positron Emission Tomography) and CAT (Computed axial tomography),

• The use of electrophysiological measures designed to measure the activation of the brain by measuring the electrical or magnetic field produced by the nervous system. This may include EEG (Electroencephalography) or MEG (Magneto-encephalography).

• The use of designed experimental tasks, often controlled by computer and typically measuring reaction time and accuracy on a particular tasks thought to be related to a specific neurocognitive process.

See also

• cognitive neuropsychology
• cognitive neuroscience
• neurocognitive
• neurology
• neuropsychological test
• neurophysiology
• philosophy of mind

Further Reading