Animal studies demonstrate that hyperactive neurons facilitate early accumulation and spread of tau and amyloid-β proteins in the pathological cascade of Alzheimer's disease (AD). Human neuroimaging studies have linked hippocampal hyperactivity to amyloid-β accumulation, apolipoprotein ε4 (APOE4) and clinical progression from prodromal AD to clinical dementia. The relationship between hippocampal hyperactivity and early AD molecular pathology (amyloid-β and tau accumulation) before clinical symptoms remains to be elucidated. Here, we studied 120 clinically normal older humans (80 females/40 males) enrolled in the Harvard Aging Brain Study. We measured functional magnetic resonance imaging (fMRI) activity during successful memory encoding and amyloid-β accumulation with PiB-positron emission tomography imaging. Additionally, we measured tau accumulation using AV1451 PET imaging in a subset of 87 participants. In this subset, we found that inferior temporal tau accumulation was associated with increased fMRI...

Distributed brain abnormalities are associated with schizophrenia. Psychoticism, disorganization, and negative symptoms are independent symptom complexes in schizophrenia; how specific neural networks are associated with these domains is unclear. By studying individuals with paranoid schizophrenia, we investigated whether dysfunction in the psychoticism domain involves even basic motor systems. Twelve males with paranoid schizophrenia were compared to 12 age, gender, and handedness matched controls. Structural T1 weighted MRI scans were acquired in a 1.5T GE scanner producing 1.5 mm continguous slices through the whole brain. Total brain volume and discrete cortical regions were measured using NIHImage. There was no significant difference in total brain volume or central sulcus length in schizophrenia. However, paranoid schizophrenia was associated with significantly larger motor knobs bilaterally (p<0.02). This finding held even when normalized to total brain volume (p<0.04). Moreover, 7 individuals with ...

Introduction: Repetitive transcranial magnetic stimulation (rTMS) exists as a feasible non-invasive and low cost therapeutic tool for those suffering from mild traumatic brain injury related headaches (MTBI-HA)[1; 2]. This study aims to assess the effec...

Metabolic mapping studies in monkeys demonstrate that auditory inputs are processed throughout the entire superior temporal gyrus (STG), much of which remains unexplored except by anatomical methods. Establishing functional subdivisions within this unexplored territory might be facilitated by relating the targets of functional studies - lesion, single-unit recording, neuroimaging, etc. - to known architectonic divisions, particularly if these could be estimated in advance on MRI scans with the aid of anatomical landmarks. To provide such correlative evidence, we prepared three brains for architectonic analysis by sectioning each one in the coronal plane and staining adjacent series with thionin, myelin, acetylcholinesterase, cytochrome oxidase, and parvalbumin. We confirmed many of the subdivisions established by Seltzer and Pandya (1978), including areas TAa, TPO, PGa, IPa, and Ts1-3. The latter areas, however, did not appear to extend into the adjacent ventral bank of the lateral sulcus, an architectonic...

Cognitively normal apolipoprotein E (APOE) ε4 carriers have greater cerebral hypometabolism than ε4 non-carriers in posterior cingulate, parietal, temporal, and frontal brain regions. To evaluate the dose-dependent effects of this common Alzheimer’s disease (AD) susceptibility gene on regional brain atrophy, we investigated the relation between APOE ε4 gene dose and gray matter concentration in 113 cognitively normal late middle-aged adults. T1-weighted volumetric magnetic resonance imaging (MRI) scans were acquired in 21 ε4 homozygotes (mean age=57±5 years; 6M/15F; Mini-Mental State Exam (MMSE)=29.6±0.7) and 33 ε4 heterozygotes (mean age=57±4 years; 8M/25F; MMSE=29.8±0.4) with reported family histories of AD and no cognitive problems or complaints and 59 demographically matched ε4 non-carriers (mean age=57±5 years; 20M/39F; MMSE=29.7±0.6). Voxel-based morphometry with SPM99 was used to transform the brain scans to a standard brain atlas, to segment them into gray matter images, and to create a statistical...

Waved-1 (wa-1) is an autosomal recessive mutation that causes a gradual decrease in transforming growth factor alpha (TGFa) expression during postnatal development. Previous studies using section reconstruction revealed that wa-1 males (on a mixed genetic background) exhibit an enlargement of the lateral ventricles with an associated late-onset deficit in fear conditioning. To evaluate the ventricular and periventricular structures more precisely, high-field (11.7 Tesla) magnetic resonance imaging (MRI) was employed. Male and female adult +/+ and wa-1 on a pure C57Bl6/J background were perfusion fixed. Three-dimensional (3D) T2 and diffusion-weighted spin-echo images of the entire brain were acquired. The lateral and third ventricles, hippocampus, amygdala, and striatum were segmented in 3D from these data. The lateral and third ventricles were enlarged by ~85% and ~50%, respectively, in +/+ females when compared to +/+ males. In addition, both male and female wa-1 mice had enlarged lateral ventricles comp...

The switching of role depending on the situation is required in both daily life and sports in order to encourage appropriate behavior. This ability is important because switching between offense and defense sometimes decides victory or defeat in a compe...

Functional magnetic resonance spectroscopy (fMRS) is an in-vivo imaging technique that shows promise towards measuring task-relevant modulation of neurotransmitters in the human brain. To more fully understand the metabolism underlying brain function, t...

This study was to investigate the relationship between the localization of neuronal activity in the cortex and the reaction time.The subjects were 4 males and 1 female. The movement task was a reaction jump to a light stimulus. Electroencephalograms (EEGs) were recorded from 19ch on the scalp according to the international 10-20 system. All EEGs were divided according to fast and slow reaction times and an average time was calculated. The average times for both fast and slow were recorded 1.5sec before to 0.5sec after each of the stimulation. The results were then analyzed by the dipole tracing method (DT). The DT results were overlapped with the magnetic resonance imaging (MRI) of each subject to determine the neuronal activity areas and its localization was determined using topography. The most negative amplitude of the fast reaction jump measured at Cz was significantly higher than in the slow reaction jump. The peak latency of the fast reaction measured at Cz was significantly earlier than in the slow ...

Parkinson’s disease (PD) is a progressive neurodegenerative disease that is typically diagnosed late in its progression. There is a need for biomarkers suitable for monitoring the disease progression at earlier stages to guide the development of novel neuroprotective therapies. One potential biomarker, α-synuclein, has been found in both the familial cases of PD, as well as the sporadic cases and is considered a key feature of PD. α-synuclein is naturally present in the retina, and it has been suggested that early symptoms of the visual system may be used as a biomarker for PD. Here, we use a viral vector to induce a unilateral expression of human wildtype α-synuclein in rats as a mechanistic model of protein aggregation in PD. We employed functional magnetic resonance imaging (fMRI) to investigate whether adeno-associated virus (AAV) mediated expression of human wildtype α-synuclein alter functional activity in the visual system. 16 rats were injected with either AAV-α-synuclein (n=7) or AAV-null (n=9) i...