Steady-state topography is a derivation of EEG/ERPs using an evoked potential to an ongoing oscillating stimuli called the steady state visually evoked potential (SSVEP). Variations in the phase difference between the SSVEP and the stimulus are interpreted to measure "summed changes in synaptic transmission time", where a latency reduction indexes an increase in synaptic excitation and a latency increase indicates a reduction in synaptic excitation (Silberstein & Nield, 2008). This kind of change at lateral prefrontal sites, particularly left lateral prefrontal sites, has been interpreted to show increased long-term memory activation to specific stimuli (Smith & Gevins, 2004). Some studies have also shown that this increased LTM activation is a predictor of future buying behavior (Silberstein & Nield, 2008).

What are the criticisms of this method? Weaknesses? Other possible interpretations?

References:

Silberstein, R., & Nield, G. (2008) Brain activity correlates of consumer brand choice shift associated with television advertising. International Journal of Advertising, 27(3), pp. 359–380.

Smith, M.E. & Gevins, A. (2004) Attention and brain activity while watching television: components of viewer engagement. Media Psychology, 6(3), pp. 285–305.

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If you have DOIs handy for the references, it's always nice to include them, as they are permanent identifiers (they will adjust if the URL of the article changes). You can link to them with http://dx.doi.org/{the rest of the identifier} If they are not handy, don't worry about it. –  Chuck Sherrington Aug 19 '13 at 14:58
(I'm not picking on you in particular, as I know a lot of others have posted references in the past few weeks) –  Chuck Sherrington Aug 19 '13 at 14:59
good point! I wish pubmed etc. would list the entire DOI in a handier format--there's a certain amount of gymnastics necessary to produce 'em, which seems silly. –  Krysta Aug 21 '13 at 16:28