In the search for the neural correlates of auditory consciousness, a candidate has been found using electroencephalography: the auditory awareness negativity (AAN). Earlier studies have investigated the AAN in response to lateralized sound. With headphones, there is a clear lateralization of AAN when two auditory lateralization cues are combined: the interaural level difference (ILD) and interaural time difference (ITD).
View Article and Find Full Text PDFPsychophysiology
November 2024
The neurological basis for perceptual awareness remains unclear, and theories disagree as to whether sensory cortices per se generate awareness. Critically, neural activity in the sensory cortices is only a neural correlate of consciousness (NCC) if it closely matches the contents of perceptual awareness. Research in vision and touch suggest that contralateral activity in sensory cortices is an NCC.
View Article and Find Full Text PDFIt may be difficult to determine whether a dichotic lag-click points to the left or right when preceded by a diotic lead-click. Previous research suggests that this loss of spatial information is most prominent at inter-click intervals (ICIs) <10 ms. However, a study by Nilsson, Tirado, and Szychowska [(2019).
View Article and Find Full Text PDFOlfactory perception is malleable and easily modulated by top-down processes such as those induced by visual and verbal information. A classic example of this is olfactory illusions where the perceived pleasantness of an odor is manipulated by the valence of a verbal label that is either visually or auditorily presented together with the odor. The mechanism behind this illusion is still unknown, and it is not clear if it is driven only by verbal information or if there is an interaction between language functions and visual mental imagery processes.
View Article and Find Full Text PDFTheories disagree as to whether it is the early or the late neural correlate of awareness that plays a critical role in phenomenal awareness. According to recurrent processing theory, early activity in primary sensory areas corresponds closely to phenomenal awareness. In support, research with electroencephalography found that in the visual and somatosensory modality, an early neural correlate of awareness is contralateral to the perceived side of stimulation.
View Article and Find Full Text PDFEcholocation is the ability to gather information from sound reflections. Most previous studies have focused on the ability to detect sound reflections, others on the ability to localize sound reflections, but no previous study has compared the two abilities in the same individuals. Our study compared echo-detection (reflecting object present or not?) and echo-localization (reflecting object to the left or right?) in 10 inexperienced sighted participants across 10 distances (1-4.
View Article and Find Full Text PDFResearch suggests that the electrophysiological correlates of consciousness are similar in hearing as in vision: the auditory awareness negativity (AAN) and the late positivity (LP). However, from a recently proposed signal-detection perspective, these correlates may be confounded by performance, as the strength of the internal responses differs between aware and unaware trials. Here, we tried to apply this signal-detection approach to correct for performance in an auditory discrimination and detection task (N = 28).
View Article and Find Full Text PDFIn hearing, two neural correlates of awareness are the auditory awareness negativity (AAN) and the late positivity (LP). These correlates of auditory awareness are typically observed with tasks in which subjects are required to report their awareness with manual responses. Thus, the correlates may be confounded by this manual response requirement.
View Article and Find Full Text PDF