Insights Revealed by EEG Data


The primary research tool utilized by Sands Research is high-density Electroencephalogram (EEG) data. When groups of neurons are activated in the brain, a small electrical charge is generated, resulting in an electrical field. EEG is a method that is used to measure these fields by placing electrodes on a person’s scalp. The measured signals are then amplified for analysis.


These electrical fields can be interpreted and projected onto a high-resolution, three-dimensional representation of a brain. The result is the ability to determine what areas of the brain are activated at specific moments.


EEG data is sampled continuously throughout our in-lab and mobile studies. Data from each sensor is sampled at least 1000 times per second in the lab, and 256 time per second in a mobile setting. When enough sensors are used, the data can be viewed in three dimensions and plotted onto a model brain. Viewing the data in this way gives insight into the brain areas engaged at any point in the shopping experience(s.) Neuropsychological knowledge can be applied to this data. For example, when a test subject gazes for an extended period of time at a product, activated brain areas help determine if the gaze was due to confusion or interest.


In addition to the insight gained from functional brain areas, the frequency of the EEG waveforms can also provide information about attention states. A complete spectral analysis is performed on the EEG.

Below is an example of a slow potential recorded from 68 channels over-layed on top of each other.  This is a response to a thirty second TV commercial.  The fast response seen at the beginning is the onset of the commercial.  The sustained response peaking in the middle is related to the story line.  Finally, the response subsides after the story line is complete.  However, the commercials ends at the conclusion of the waveforms.  This loss of activity reflects a loss of attention to the commercial.


SANDS RESEARCH INC. 955 N Resler 104-113

El Paso, TX 79912

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