Neuropsychology is a branch of psychology that aims to understand how the structure and function of the brain relates to specific psychological processes.
It is strongly scientific in its approach and shares an information processing view of the mind with cognitive psychology and cognitive science.
It is one of the most eclectic of the psychological disciplines, overlapping at times with areas such as neuroscience, philosophy (particularly philosophy of mind), neurology, psychiatry and computer science (particularly by making use of artificial neural networks).
In practice neuropsychologists tend to work in academia (involved in basic or clinical research), clinical settings (involved in assessing or treating patients with neuropsychological problems - see clinical neuropsychology), forensic settings (often assessing people for legal reasons or court cases or working with offenders) or industry (often as consultants where neuropsychological knowledge is applied to product design).
Experimental neuropsychology is an approach which uses methods from experimental psychology to uncover the relationship between the nervous system and cognitive function. The majority of work involves studying healthy humans in a laboratory setting, although a minority of researchers may conduct animal experiments. Human work in this area often takes advantage of specific features of our nervous system (for example that visual information presented to a specific visual field is preferentially processed by the cortical hemisphere on the opposite side) to make links between neuroanatomy and psychological function.
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.
Methods and tools
- 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
- The use of 'brain scanners' or functional neuroimaging 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
- 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.