Open AccessEchoic Memory: Investigation of Its Temporal Resolution by Auditory Offset Cortical Responses
Author(s) -
Makoto Nishihara,
Koji Inui,
Tomoyo Morita,
Minori Kodaira,
Hideki Mochizuki,
Naofumi Otsuru,
Eishi Motomura,
Takahiro Ushida,
Ryusuke Kakigi
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0106553
Subject(s) - magnetoencephalography , echoic memory , latency (audio) , stimulus (psychology) , sensory memory , auditory cortex , audiology , neuroscience , sensory system , offset (computer science) , psychology , computer science , electroencephalography , mismatch negativity , medicine , cognition , telecommunications , psychotherapist , programming language
Previous studies showed that the amplitude and latency of the auditory offset cortical response depended on the history of the sound, which implicated the involvement of echoic memory in shaping a response. When a brief sound was repeated, the latency of the offset response depended precisely on the frequency of the repeat, indicating that the brain recognized the timing of the offset by using information on the repeat frequency stored in memory. In the present study, we investigated the temporal resolution of sensory storage by measuring auditory offset responses with magnetoencephalography (MEG). The offset of a train of clicks for 1 s elicited a clear magnetic response at approximately 60 ms (Off-P50m). The latency of Off-P50m depended on the inter-stimulus interval (ISI) of the click train, which was the longest at 40 ms (25 Hz) and became shorter with shorter ISIs (2.5∼20 ms). The correlation coefficient r 2 for the peak latency and ISI was as high as 0.99, which suggested that sensory storage for the stimulation frequency accurately determined the Off-P50m latency. Statistical analysis revealed that the latency of all pairs, except for that between 200 and 400 Hz, was significantly different, indicating the very high temporal resolution of sensory storage at approximately 5 ms.