being, and can be classified into five main categories; alpha, beta, theta and delta (Zurawicki 2010; Genco et al. 2013). Figure X is a summary of each of these brain-waves.

Figure 4: Summary of Brain-Waves Properties based on Genco et al. (2013) and Zurawicki (2010)
Zurawicki (2010) explains how the ‘disadvantages of EEG is that the electric conductivity, and therefore the measured electrical potentials can vary widely from person to person and at different time frames.’ (p. 49). He explains that is due to the fact that tissues in the body such as brain matter, blood and bones have ‘different conductivities for electrical signals’ (p.49).
Eye tracking, on the other hand, is a powerful tool for analysing behaviour and cognition of a test participant during a research project by analysing a number of important features (Zurawicki 2010). Genco et al. (2013) explain how these include; (1) the speed of eye movement, (2) duration of fixation, (3) pattern and frequency of blinks and (4) patterns of searching behaviour.
Fixations occur when the eye movement stops the retina on a particular object; that is a person’s eye stops and look (fixate) in certain position (Duchowski 2007; Zurawicki 2010; Genco et al. 2013). Fixations duration varies from 150ms to 600ms (Duchowski 2007) and Zurawicki (2010), continue explaining that the ‘resulting series of fixations and saccades is called a scan path’, which are used to analyse ‘visual perception, cognitive intent, interest and salience (p.51).

Saccade are eye movements from one fixation to another (Zurawi