Electrophysiological correlates of spatial orienting towards angry faces: A source localization study

No abstract

The event-related potential (ERP) and event-related field (ERF) techniques provide valuable insights into the time course of processes in the brain. Because neural signals are typically weak, researchers commonly filter the data to increase the signal-to-noise ratio. However, filtering may distort the data, leading to false results. Using our own EEG data, we show that acausal high-pass filtering can generate a systematic bias easily leading to misinterpretations of neural activity. In particular, we show that the early ERP component C1 is very sensitive to such effects. Moreover, we found that about half of the papers reporting modulations in the C1 range used a high-pass digital filter cut-off above the recommended maximum of 0.1 Hz. More generally, among 185 relevant ERP/ERF publications, 80 used cutoffs above 0.1 Hz. As a consequence, part of the ERP/ERF literature may need to be re-analyzed. We provide guidelines on how to minimize filtering artifacts.

Over the past two decades, considerable evidence has accumulated for the notion that threat-related cognitive biases play a significant role in individual differences in anxiety (for reviews, see Bar-Haim et al., 2007;Mogg and Bradley, 1998). Most cognitive models of threat processing in anxiety delineate a sequence of steps describing how information is processed as it progresses through the cognitive system (Beck and Clark, 1997;Beck, Emery and Greenberg, 1985;Mogg and Bradley, 1998;Rapee and Heimberg, 1997;Williams et al., 1988). Theory-driven parsing of these cognitive mechanisms provides a particularly useful framework for organizing predictions when examining the specific brain structures and neural mechanisms that are involved in biased threat processing. The current chapter reviews how available neuroscience techniques, in conjunction with classic cognitive tasks, may be applied to examine both the chronometry and the neural architecture associated with threat biases in anxious individuals. Special consideration will be given to the application of such techniques in paediatric populations and in a developmental context. Finally, we selectively review studies using neuroscience techniques to investigate anxiety as an illustration of the potential this approach has for bettering our understanding of these disorders. In doing so, we will focus on a classic attention paradigm -the dot-probe task. Readers who are interested in more exhaustive reviews of this literature are referred to Pine (2007); Rauch, Shin and Wright (