Introduction: In the brain of premature infants primary intracerebral hemorrhage (ICH) is a common occurrence. It is usually unilateral and deep in the cerebrum near the ganglionic eminence beside the lateral ventricle. Blood can extend into the ventricles causing hydrocephalus. Even small lesions of this type, are associated with poor developmental outcome including cerebral palsy and mental retardation. The purpose of this study was to obtain magnetic resonance images (MRI) of the mouse brain after ICH and to correlate the images with histological evolution. Methods: ICH was induced in one-day-old mice, which are developmentally similar to a 24-26 weeks human fetus, by injection of autologous blood into the striatum. MRI was obtained 15 minutes to 48 hours later. Mice were perfused with 4% paraformaldehyde 8 hours to 28 days later. H&E, immunohistochemical, and TUNEL staining were used to quantify the lesion area, neutrophils, microglia, and cell death at the edge of the hemorrhagic lesion. Results: Hist...

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...

Visual motion provides a powerful cue for identifying the surfaces of three-dimensional visual objects. Using functional magnetic resonance imaging (MRI) of the human brain, we found that occipital cortex, the motion processing area MT/MST, and intraparietal cortex are involved in the representation of motion-defined curved and flat surfaces. Additionally, neural responses associated with the perception of motion-defined curved and flat surfaces differed more in early visual cortex than in the MT/MST complex (Jiang et al, 1999). To investigate whether the differential responses to curved and flat motion-defined surfaces are restricted to a subset of early visual cortical areas, we examined activations in occipital cortex partitioned by retinotopically-defined visual areas. We found strong differential activations to motion-defined curved and flat surfaces in V1 and V2 in all three subjects examined (P < .05), but not in areas V3 and V4 (P > .4), even though neurons in these areas have much larger receptive...

Empirical data from Functional Magnetic Resonance Imaging (FMRI) of human brain have revealed variations in response delay on the order of 10 seconds [1,2,3]. This relatively wide range of delays has been attributed to the delayed flow of blood through large veins draining the sites of neuronal activation [1,2]. This study examined the difference in response delays between large blood vessels and parenchyma using two independent, unbiased methods for classifying activated voxels as vessel- or parenchyma- related. FMRI images (BOLD EPI, 1.5 T. voxel size 3.75 × 3.75 ×4 mm) from 3 subjects were obtained during visual stimulation consisting of a checkered annulus centered on a gray fixation point alternating with fixation alone. High-resolution FMRI images (3T, voxel size 1.0×1.0 ×1.2 mm) were also obtained for one of the subjects. In the first classification method, we imaged blood vessels directly using 2D-TOF MRI capable of resolving blood vessels greater than 2 mm in diameter. Stimulus-activated voxels we...

Co-registering functional brain images across subjects offers experimental advantages and is widely used for studies in humans. Voxel-based co-registration methods require a high-quality 3D template image. Here we describe the formation of T1-weighted structural MRI and PET blood flow template images for baboon and Macaca nemestrina. The images derive from 9 baboons, 12 macaques, and over 500 PET [15O]water scans. Custom software aligns individual MR images to the MRI template using a 12-parameter (affine) model. In the realigned baboon MR images, subcortical test points correspond closely to a photomicrographic atlas with an average error of 1.53mm. Cortical test points on average were within 1.99mm of the mean location for each point. Alignment of individual PET blood flow images directly to the PET template was compared to a two-step alignment process via each subject's MR image. The two transformations were identical within 0.41 mm, 0.54 degrees, and 1.0 percent (translation, rotation, and linear stret...

Introduction: Deception is a psychological process by which one individual deliberately attempts to convince another to accept as true what the first individual knows to be false. To deceive other person requires inhibition of true response and producti...

Major Depressive Disorder (MDD) is a mood disorder with a lifetime prevalence of approximately 20% in the US [1]. MDD is characterized by persistent feelings of sadness and apathy not attributable to any apparent external causes [1]. Fronto-limbic circu...

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...

Traumatic brain injury (TBI) elicits an inflammatory response in the CNS that involves both resident and peripheral immune cells. In this pilot study, we characterize a cryoinjury animal model of TBI using MRI and histopathology, to study its pathogenes...