The purpose of this study was to determine brain networks involved in motion perception of sounds. Ten healthy young volunteers measured their brain activity during a sound localization task and control tasks using functional MRI. An event-related design was used in this study. Stereo sounds moving in the 3D space were created by a personal computer, and presented binaurally through a pair of air conduct headphones during the sound localization task. And subjects were asked to judge the location and direction of the moving sounds. During the control task, non-moving sounds were used for stimuli. The intraparietal, premotor cortices of the bilateral hemisphere, and the cerebellar vermis were specifically activated during the sound localization task. These areas are believed to be involved in control of eye movements. Although, task-related eye movements were not observed in this study. Therefore, our results indicate that brain networks consist of these areas are related to motion perception of sounds, and ...

In order to find out whether it is possible to detect EH with a 4.7 T MRI device, five guinea pigs were used for evaluating the dynamic change of gadolinium uptake in normal cochlea n=15 and experimental induced EH. Two kinds of operation were used to obtain an EH-endolymphatic sac (ES) intact group (n=6) and ES -damaged group (n=9). D-aldosterone (1 mg/kg) was given to 6 animals in the ES -damaged group, injected 8-9 days after ES surgery. MRI was performed and hearing was tested by ECoG in the ES- damaged group. It was found that as early as 5 days after ES surgery, EH started in all animals as verified by MRI scannings and histology. Serious damage to the inner ear barrier was detected with MRI in one advanced stage animal, which received D-aldosterone injection with a 60 dB hearing loss. Three areas of the cochlea were measured and area factor with scala vestibuli or scala tympani as reference were used for quantitative evaluation of EH. For EH to be defined as being present 87.5 % (7/8) of all the are...

This study examines the cognitive and neural systems involved in attentional conflict and their development using functional magnetic resonance imaging. Attentional conflict was manipulated by presenting compatible (> > >) or incompatible (> < >) flankers on either side of a target stimulus. Subjects were instructed to press the right button if the center arrow pointed right (>) and the left button if the center arrow pointed left (<). The salience of flankers was manipulated by parametrically varying the number of compatible trials preceding an incompatible trial by 1, 3 or 5. Eight subjects (4 female) were scanned using a rapid mixed trial design during performance of the task. Adults and children were faster on compatible (518 and 678 msec) than incompatible trials (580 and 786 msec). Reaction times and activity in the anterior cingulate and dorsolateral prefrontal cortex increased for incompatible trials as a function of preceding context (1, 3, or 5 compatible trials) for the adults. Children showed l...

MRI studies using the manual tracing method have shown a smaller than normal hippocampal volume in patients with post-traumatic stress disorder (PTSD). However, these studies have yielded inconsistent results, and brain structures other than the hippocampus have not been well investigated. A recently developed, fully-automated method called voxel-based morphometry (VBM) enables an exploration of structural changes throughout the brain by applying statistical parametric mapping to high-resolution MRI. Here we firstly utilized this technology in patients with PTSD. Participants were nine victims of the Tokyo subway sarin attack with PTSD and sixteen matched victims of the same traumatic event without PTSD. The VBM showed a significant gray matter volume reduction in the left anterior cingulate cortex (ACC) in traumatic-survivors with PTSD compared with those without PTSD. The severity of the disorder was negatively correlated with the gray matter volume of the left ACC in PTSD subjects. There were no signifi...

Background: Psychotic symptoms in AD (AD with psychosis, AD+P) identify a heritable phenotype associated with more rapid deterioration in frontotemporal cognitive functions. Functional imaging and post-mortem studies indicate that AD+P may not be a random consequence of diffuse brain illness, but result from specific regional pathology. To our knowledge, there are no studies employing a voxel-based morphometric (VBM) approach to elucidate the structures that could be abnormal in AD+P. Objective: To conduct VBM analyses of structural MRIs in subjects with AD+P and matched subjects without psychosis (AD-P). Methods: Subjects (AD-P=22; AD+P=18) were assessed as part of participation in the Alzheimer Disease Research Center at the University of Pittsburgh. The presence of psychotic symptoms was assessed using the CERAD Behavioral Rating Scale. These groups were matched for age, gender, number of years of education, and duration of AD. Statistical Parametric Mapping (SPM 99) was used for image processing. All i...

Purpose: FMRI studies were performed using a Go-No-Go task (GNG) and a Counting Interference task (CI) to determine whether aggressive Disruptive Behavior Disorder (DBD) subjects show lower frontal lobe fMRI activation as compared to controls. Methods: 15 DBD and 16 normal subjects were recruited. All subjects and their parents rated the subjects’ violent media exposure (VME). The DBD group had a significantly higher VME than the control group. Using 3D EPI sequence fMRI data were acquired while subjects performing the tasks. The GNG task required the subject to press a button for any presented letter, except X. The CI task required the subjects to press a button corresponding to the number of Xs for control periods and of identical numerals for activation periods, in which the numeral did not agree with the number of stimuli. Results: There was no difference of behavior performance between DBD subjects and normal subjects. For GNG task, fMRI group map showed activation in the right DLPFC significantly gre...

The propensity for transient elevation of blood pressure to suppress diaphragmatic muscle activity, and, preferentially, upper airway muscle tone, suggests a mechanism by which an airway already compromised by anatomical features might be placed at risk for complete obstruction in OSA patients, namely exaggerated somatomotor suppression by pressor challenges. We examined signal changes in neural sites recruited during a cold pressor challenge to the forehead. A series of 20 image slices (25 repetitions, Echo Planar technique) through the brain of 7 male OSA patients (43-59 yrs) and 6 control subjects (29-59 yrs) was collected during 1 min baseline and 1.5 min application of a bag of cold (3oC) deuterium oxide to the forehead in a GE 1.5T Signa scanner. Images collected during baseline and challenge conditions were subjected to a fixed-effects analysis using the SPM imaging package. Both control and OSA subjects showed significantly increased signals in multiple areas, including the caudate nucleus, hippoca...

Previous functional neuroimaging studies have characterized brain systems mediating associative learning using classical delay conditioning paradigms. In the present study, we used event-related functional magnetic resonance imaging to characterize neuronal responses mediating aversive trace conditioning. During conditioning, neutral auditory tones were paired with an aversive sound [unconditioned stimulus (US)]. We compared neuronal responses evoked by conditioned (CS+) and nonconditioned (CS−) stimuli in which a 50% pairing of CS+ and the US enabled us to limit our analysis to responses evoked by the CS+ alone. Differential responses (CS+ vs CS−), related to conditioning, were observed in anterior cingulate and anterior insula, regions previously implicated in delay fear conditioning. Differential responses were also observed in the amygdala and hippocampus that were best characterized with a time × stimulus interaction, indicating rapid adaptation of CS+-specific responses in medial temporal lobe. These...

Language and music exhibit similar acoustic and structural properties, and both appear to be uniquely human. Several recent studies suggest that speech and music perception recruit shared computational systems, and a common substrate in Broca's area for hierarchical processing has recently been proposed. However, this claim has not been tested by directly comparing the spatial distribution of activations to speech and music processing within subjects. In the present study, participants listened to sentences, scrambled sentences, and novel melodies. As expected, large swaths of activation for both sentences and melodies were found bilaterally in the superior temporal lobe, overlapping in portions of auditory cortex. However, substantial nonoverlap was also found: sentences elicited more ventrolateral activation, whereas the melodies elicited a more dorsomedial pattern, extending into the parietal lobe. Multivariate pattern classification analyses indicate that even within the regions of blood oxygenation le...

Although it is well documented that the ability to perceive biological motion is mediated by the lateral temporal cortex, whether and when neural activity in this brain region is modulated by attention is unknown. In particular, it is unclear whether the processing of biological motion requires attention or whether such stimuli are processed preattentively. Here, we used functional magnetic resonance imaging, high-density electroencephalography, and cortically constrained source estimation methods to investigate the spatiotemporal effects of attention on the processing of biological motion. Directing attention to tool motion in overlapping movies of biological motion and tool motion suppressed the blood oxygenation level-dependent (BOLD) response of the right superior temporal sulcus (STS)/middle temporal gyrus (MTG), while directing attention to biological motion suppressed the BOLD response of the left inferior temporal sulcus (ITS)/MTG. Similarly, category-based modulation of the cortical current source...