Wechsler Intelligence Scales and Brain Region Mapping
The Wechsler Adult Intelligence Scale (WAIS) and brain area and function mapping can be indices and quotients of the WAIS. Especially when considering mapping to specific areas of the brain for processing while taking the test. Mapping can be done using PET, MRI, SPEC, fMRI, EEG, and QEEG technologies. For the most part, there is evidence to suggest that using EEG and WAIS together would result in performing better assessments than each by themselves and provide more information on the source of psychological dysfunction for the development of treatment plans.
Korbian Brodman, a German neurologist is famous for dividing up the brain into 52 distinct regions based on their characteristics and created a map that shows regions of the brain that are relatively stable across all species of mammals. Some regions also map nicely to cognitive function. With respect to intelligence test like the WAIS, specific Brodman areas are associated with cognitive function such as B10, 11, 46 is associated with cognitive emotional valence, and B45, 47, 46 is associated with working memory. Furthermore, another mapping system called, the 10-20 system is projections of brain areas on the surface of the skull for the purpose of doing electroencephalograms assessments (quantitative EEG – QEEG) and neuromodulation training. For example, if the WAIS WMI index indicated a problem, the clinician would focus on B45, 47, 46 that is located in the prefrontal cortex and projected to site Fp1 on the scull. This is the location where an EEG sensor would be attached for further assessment of brain dysregulation or training for performance optimization.
Traumatic brain injury effects intellectual functioning as seen on WAIS test results and used in the assessment and rehabilitation of these patients. However, many of these patients are expected to perform poorly on the WAIS, which is a known deficiency because it only indicates a problem but not where the problem is or what brain function is causing it, as well as it is known that the WAIS is not a good test of intelligence in brain injury cases.
More advanced research is focused on the relationship among brain regions and how they might work together like a network. Researchers have found using QEEG brain mapping there is a correlation of distributed intelligence processing occurring while taking the WAIS, and particular high associations of multiple brain areas in visual and verbal processing. Observed phase lock and shift relationship among theta and beta band EEG frequencies show a high correlation of high intelligence scores and short phase lock in theta frequencies and long phase lock in beta frequencies. These relationships occur in short distance brain area connections and most of this activity takes place in the left hemisphere.
The WAIS and similar other intelligence tests that have a wide usage and have strong validation measures are demonstrated to be effective and useful tools for psychological and neurological assessments. Recently, technology for performing bio-medical assessments such as PET, CT, MRI, fMRI, and others are being applied in the fields of clinical psychology and neuroscience. In particular, the QEEG and EEG studies are showing how these neuro-assessment and training technologies can be used in combination with the WAIS to provide more information to both the clinician and client for deciding on how to best develop a treatment plan and execute on it.