Brain activity supporting alternating speech for semantic words: simultaneous magnetoencephalographic recording.

Communication, especially conversation, is essential for human social life. Many previous studies have examined the neuroscientific underpinnings of conversation, i.e.

Differential working memory function between phonological and visuospatial strategies: a magnetoencephalography study using a same visual task.

Previous studies have reported that, in working memory, the processing of visuospatial information and phonological information have different neural bases. However, in these studies, memory items were presented via different modalities. Therefore, the modality in which the memory items were presented and the strategy for memorizing them were not rigorously distinguished.

Magnetoencephalography Hyperscanning Evidence of Differing Cognitive Strategies Due to Social Role During Auditory Communication.

Auditory communication is an essential form of human social interaction. However, the intra-brain cortical-oscillatory drivers of auditory communication exchange remain relatively unexplored. We used improvisational music performance to simulate and capture the creativity and turn-taking dynamics of natural auditory communication.

Construction of a fiber-optically connected MEG hyperscanning system for recording brain activity during real-time communication.

Communication is one of the most important abilities in human society, which makes clarification of brain functions that underlie communication of great importance to cognitive neuroscience. To investigate the rapidly changing cortical-level brain activity underlying communication, a hyperscanning system with both high temporal and spatial resolution is extremely desirable. The modality of magnetoencephalography (MEG) would be ideal, but MEG hyperscanning systems suitable for communication studies remain rare.

Processing time affects sequential memory performance beginning at the level of visual encoding.

Electrophysiological studies have demonstrated that theta-band activity is useful for investigating neural mechanisms of memory. However, mechanisms specifically driving memory performance remain poorly understood. In sequential memory, performance can be artificially attenuated by shortening the inter-stimulus interval (ISI) between memory item presentations.

Semi-automated brain responses in communication: A magnetoencephalographic hyperscanning study.

Face to face communication is interactive, and involves continuous feedforward and feedback of information, thoughts, and feelings to the opposite party. To accurately assess the neural processing underlying these interactions, synchronous and simultaneous recording of the brain activity from both parties is needed, a method known as hyperscanning. Here, we investigated the neural processing underlying nonverbal face-to-face communication using a magnetoencephalographic (MEG) hyperscanning system, comprising two fiber optically connected MEGs.

Functional decline of the precuneus associated with mild cognitive impairment: Magnetoencephalographic observations.

Mild Cognitive Impairment (MCI) is a border or precursor state of dementia. To optimize implemented interventions for MCI, it is essential to clarify the underlying neural mechanisms. However, knowledge regarding the brain regions responsible for MCI is still limited.

Different roles for theta- and alpha-band brain rhythms during sequential memory.

Numerous studies have demonstrated that brain rhythms are modulated according to memory performance or memory processing. In sequential memory tasks, memory performance can be reduced by shortening the intervals between memory item presentations. To clarify the neurophysiological mechanism underlying this, we recorded magnetoencephalograms in 33 healthy volunteers performing two sequential memory tasks with either short or long intervals between memory items (hereafter, fast and slow conditions, respectively).

Appearance and modulation of a reactive temporal-lobe 8-10-Hz tau-rhythm.

Spontaneous 8- to 10-Hz "tau-rhythm" in magnetoencephalographic (MEG) recordings has been reported to originate in the auditory cortex and be suppressed by sound. For unknown reasons however, tau-rhythm is often difficult to detect. In this study, we sought to characterize its emergence and auditory reactivity.

Multiple Brain Activities During Sequential Memory Encoding - MEG Study Of Modulation Of Alpha-Band Rhythm.

It is known that alpha-band rhythm during memory maintenance is enhanced by increasing memory load. This enhancement is generally thought to be caused by active inhibition of task-irrelevant visual inputs. During sequential memory processing, we previously found that alpha-band activity increases from beginning to midterm during memory encoding, and conversely decreases from midterm to ending.

Turning a cylindrical treadmill with feet: An MR-compatible device for assessment of the neural correlates of lower-limb movement.

Background: Locomotion, which is one of the most basic motor functions, is critical for performing various daily-life activities. Despite its essential function, assessment of brain activity during lower-limb movement is still limited because of the constraints of existing brain imaging methods.

New Method: Here, we describe an MR-compatible, cylindrical treadmill device that allows participants to perform stepping movements on an MRI scanner table.

Spectral-Spatial Differentiation of Brain Activity During Mental Imagery of Improvisational Music Performance Using MEG.

Group musical improvisation is thought to be akin to conversation, and therapeutically has been shown to be effective at improving communicativeness, sociability, creative expression, and overall psychological health. To understand these therapeutic effects, clarifying the nature of brain activity during improvisational cognition is important. Some insight regarding brain activity during improvisational music cognition has been gained via functional magnetic resonance imaging (fMRI) and electroencephalography (EEG).

Speech Disfluency-dependent Amygdala Activity in Adults Who Stutter: Neuroimaging of Interpersonal Communication in MRI Scanner Environment.

Affective states, such as anticipatory anxiety, critically influence speech communication behavior in adults who stutter. However, there is currently little evidence regarding the involvement of the limbic system in speech disfluency during interpersonal communication. We designed this neuroimaging study and experimental procedure to sample neural activity during interpersonal communication between human participants, and to investigate the relationship between the amygdala activity and speech disfluency.

Alpha-band rhythm suppression during memory recall reflecting memory performance.

Alpha-band rhythm is thought to be involved in memory processes, similarly to other spontaneous brain rhythms. Ten right-handed healthy volunteers participated in our proposed sequential short-term memory task that provides a serial position effect in accuracy rate. We recorded alpha-band rhythms by magnetoencephalography during performance of the task and observed that the amplitude of the rhythm was suppressed dramatically in the memory recall period.

Acoustic pressure reduction at rhythm deviants causes magnetoencephalographic response.

Rhythm is an element of music and is important for determining the impression of the music. To investigate the mechanism by which musical rhythmic changes are perceived, magnetoencephalographic responses to rhythm deviants were recorded from 11 healthy volunteers. Auditory stimuli consisting of physically controlled tones were adapted from a song.

Activity in the left auditory cortex is associated with individual impulsivity in time discounting.

Impulsivity dictates individual decision-making behavior. Therefore, it can reflect consumption behavior and risk of addiction and thus underlies social activities as well. Neuroscience has been applied to explain social activities; however, the brain function controlling impulsivity has remained unclear.

Functional modulations in brain activity for the first and second music: a comparison of high- and low-proficiency bimusicals.

Bilingual studies have shown that brain activities for first (L1) and second (L2) languages are influenced by L2 proficiency. Does proficiency with a second musical system (M2) influence bimusical brains in a manner similar to that of bilingual brains? Our magnetoencephalography study assessed the influence of M2 proficiency on the spatial, strength, and temporal properties of brain activity in a musical syntactic-processing task (i.e.

Activation of auditory cortex by anticipating and hearing emotional sounds: an MEG study.

To study how auditory cortical processing is affected by anticipating and hearing of long emotional sounds, we recorded auditory evoked magnetic fields with a whole-scalp MEG device from 15 healthy adults who were listening to emotional or neutral sounds. Pleasant, unpleasant, or neutral sounds, each lasting for 6 s, were played in a random order, preceded by 100-ms cue tones (0.5, 1, or 2 kHz) 2 s before the onset of the sound.

Magnetic displacement force and torque on dental keepers in the static magnetic field of an MR scanner.

Purpose: To evaluate the effect of the static magnetic field of magnetic resonance (MR) scanners on keepers (ie, ferromagnetic stainless steel plate adhered to the abutment tooth of dental magnetic attachments).

Materials And Methods: Magnetically induced displacement force and torque on keepers were measured using 1.5 Tesla (T) and 3.

Alpha-band rhythm modulation under the condition of subliminal face presentation: MEG study.

The human brain has two streams to process visual information: a dorsal stream and a ventral stream. Negative potential N170 or its magnetic counterpart M170 is known as the face-specific signal originating from the ventral stream. It is possible to present a visual image unconsciously by using continuous flash suppression (CFS), which is a visual masking technique adopting binocular rivalry.

Amplitude modulation of alpha-band rhythm caused by mimic collision: MEG study.

Detection of a collision risk and avoiding the collision are important for survival. We have been investigating neural responses when humans anticipate a collision or intend to take evasive action by applying collision-simulating images in a predictable manner. Collision-simulating images and control images were presented in random order to 9 healthy male volunteers.

Neural representation of scale illusion: magnetoencephalographic study on the auditory illusion induced by distinctive tone sequences in the two ears.

The auditory illusory perception "scale illusion" occurs when a tone of ascending scale is presented in one ear, a tone of descending scale is presented simultaneously in the other ear, and vice versa. Most listeners hear illusory percepts of smooth pitch contours of the higher half of the scale in the right ear and the lower half in the left ear. Little is known about neural processes underlying the scale illusion.

Magnetoencephalography evidence for different brain subregions serving two musical cultures.

Individuals who have been exposed to two different musical cultures (bimusicals) can be differentiated from those exposed to only one musical culture (monomusicals). Just as bilingual speakers handle the distinct language-syntactic rules of each of two languages, bimusical listeners handle two distinct musical-syntactic rules (e.g.

Does the human dorsal stream really process a category for tools?

Previously, Almeida et al. (2008) used a technique called Continuous Flash Suppression to show that human dorsal stream cortical areas specifically responded to a "tool category." Here, we used the same technique to clarify what attributes of tools are processed in the dorsal stream.

Two-dimensional mapping of impedance magnetocardiograms.

A new method for measuring two-dimensional (2-D) impedance magnetocardiograms (I-MCGs) and magnetocardiograms (MCGs) above the heart simultaneously, has been developed. The I-MCG's and MCG's signals are recorded by using a superconducting interference device (SQUID) system. To measure the I-MCG and MCG signals, four first-order gradiometers with an 18-mm diameter and a 50-mm baseline were used.