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Pseudo-random procedures for rapid presentation rates using optical imaging and spectroscopy.

J Martindale·J Berwick·D Johnston·M Jones·Y Zheng·P Coffey·M Paley·J Mayhew
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Abstract

Optical imaging of rat barrel cortex has provided detailed spatio-temporal maps of functional cortical architecture. We describe an event-related procedure (ERP) for optical imaging based on selective signal averaging as reported by Burock et al., using an anti-correlative pseudo-random event sequence. The sequence used 1 s vibrissal stimulation at 5 Hz, with an interevent interval of 2 s. This rapid presentation rate allows for greater statistical power per unit time, and allows for direct comparison of event-related studies with other imaging modalities. The spatio-temporal characteristics of single wavelength and spectrographic results were found to be comparable with those obtained by standard techniques, although a general lessening of haemodynamic response function (HRF) was noted. We also describe a method of locating barrel activity by spectral analysis of summed event data. Using this technique, the power spectrum of remitted light from the barrel region was found to peak within +/- 0.12 Hz of the inter-event interval frequency.

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AlgorithmsAnimalsCerebral CortexElectric StimulationElectrophysiologyEvoked PotentialsEvoked Potentials, SomatosensoryHemoglobinsOxyhemoglobinsRatsReaction TimeSpectrophotometryVibrissaeComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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J Martindale, J Berwick, D Johnston, M Jones, Y Zheng, P Coffey, M Paley, J Mayhew. 2000-07-14. Pseudo-random procedures for rapid presentation rates using optical imaging and spectroscopy.. https://doi.org/10.1097/00001756-200007140-00037

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