Objective: Olfactory dysfunction is associated with Alzheimer’s Disease development. Our previous study revealed that odor identification tasks activated several olfactory brain regions more than odor memory tasks. In this study, we examined if apolipop...

The cingulate gyrus, a brain area important for certain cognitive functions, is pathologically involved in the very early stages of Alzheimer’s disease. In this study we investigated the extent of change in this region as a function of healthy aging. Participants consisted of: 1) 41 elderly individuals with normal cognition (mean age: 79.1, range: 67-89); and 2) 27 young adults (mean age: 28.1, range: 22-35). They all underwent a high resolution MRI scan. The cingulate gyrus was segmented from 1.6 mm gapless T1 weighted images using the protocol described by Killiany et al. (Ann Neurol., 2000). For each hemisphere, the volumes of the cingulate gyrus and cortex were derived separately. To correct for individual differences in brain size, the volumes of regions of interest were divided by total intracranial volume. The young participants differed significantly from the old in normalized total (right+left) cingulate gyrus (p<0.001) and cortex (p<0.001) volumes. Further analyses indicated that these age-relate...

Brain development in the first 2 years after birth is extremely dynamic and likely plays an important role in neurodevelopmental disorders, including autism and schizophrenia. Knowledge regarding this period is currently quite limited. We studied structural brain development in healthy subjects from birth to 2. Ninety-eight children received structural MRI scans on a Siemens head-only 3T scanner with magnetization prepared rapid gradient echo T1-weighted, and turbo spin echo, dual-echo (proton density and T2 weighted) sequences: 84 children at 2–4 weeks, 35 at 1 year and 26 at 2 years of age. Tissue segmentation was accomplished using a novel automated approach. Lateral ventricle, caudate, and hippocampal volumes were also determined. Total brain volume increased 101% in the first year, with a 15% increase in the second. The majority of hemispheric growth was accounted for by gray matter, which increased 149% in the first year; hemispheric white matter volume increased by only 11%. Cerebellum volume increa...

Functional magnetic resonance imaging (fMRI) studies have revealed that activity in the medial temporal lobe (MTL) predicts subsequent memory performance in humans. Because of limited knowledge on cytoarchitecture and axonal projections of the human MTL, precise localization and characterization of the areas that can predict subsequent memory performance are benefited by the use of nonhuman primates in which integrated approach of the MRI- and cytoarchiture-based boundary delineation is available. However, neural correlates of this subsequent memory effect have not yet been identified in monkeys. Here, we used fMRI to examine activity in the MTL during memory encoding of events that monkeys later remembered or forgot. Application of both multivoxel pattern analysis and conventional univariate analysis to high-resolution fMRI data allowed us to identify memory traces within the caudal entorhinal cortex (cERC) and perirhinal cortex (PRC), as well as within the hippocampus proper. Furthermore, activity in the...

Background: The ubiquitous nature and profound physiologic effects of muscarinic receptors in the brain has limited the ability of functional magnetic resonance imaging (fMRI) to detect activations of the acetylcholine system. Pharmacological MRI (phMRI) using Blood Oxygen Level Dependent (BOLD) and cerebral blood flow (CBF) methods were developed to spatially identify muscarinic subtype-1 receptor activation in the rat. Objective: to spatially identify the M1 receptor activation using phMRI with the selective M1 agonist McN-A-343 in the rat. Methods: Male Wistar rats were imaged with a Bruker 4.7T magnet using both echo planar imaging with continuous arterial spin labeling and with fast spin echo techniques. In order to obtain dose-response curves, various doses (0.04 to 4.0 mg/kg) (n=6 per dose) of the selective M1 receptor agonist McN-A-343 were given IV. Heart rate, arterial blood pressure, and respiratory rate were continuously recorded. Placebo injections were performed before the study drug. Data we...

In recent years white matter tissue is being regarded as a dynamic tissue that undergoes activity-dependent structural changes (Fields, 2015). The White matter consists mainly of myelinated and non-myelinated axons, forming networks which are necessary ...

Today whole-brain imaging in multiple modalities enables neuroscientists to acquire brain datasets of different animal models at various developmental stages. Here we present a toolchain called “HeadLight” (a cross-platform GUI application built using C...

Overweight and obesity are public health problems that affect 30% of the world's population. It is known that this accumulation of body mass causes increased blood pressure, insulin resistance, diabetes, among other comorbidities. But overweight also af...

Background: Child neglect is a pervasive pediatric problem, frequently associated with disturbed mother-infant attachment. However, little is known about the neurobiological substrate underlying this relationship. This pilot study of healthy mother-infant dyads aims to examine brain regions activated in response to infant facial cues, and to explore the possible role of oxytocin in facilitating this interaction. Methods: Eight right-handed healthy mothers were enrolled, along with their infants aged between 3 and 8 months. Serum oxytocin levels levels were obtained sequentially during a standardized period of mother-infant interaction, during which the infant's facial expressions were videotaped. Functional MRI was then used to measure maternal brain activity in response to these facial images, compared with familiar and unknown facial images. Results: In comparing responses to the mothers’ own infants versus familiar but unknown infants, significantly increased brain responses (p<0.005) were seen in the v...

Brain slices provide a controllable in situ model for investigating the biophysical basis of water diffusion in nervous tissue. Yet only acute studies are possible because brain slices seldom remain viable beyond 12 hrs due to cell death processes initiated by procurement. This limitation may be overcome by developing diffusion MRI methods for organotypic cultures, which remain viable for many weeks. In the present study, hippocampal slices were procured from P7 rat pups and cultured for 10 days on Millipore culture plate inserts. The inserts then were placed into an NMR tube and imaged using a 15mm birdcage coil in a 750-MHz wide-bore spectrometer. Although the small volume of cultured slices (~ 0.8 mm3) limited available signal-to-noise (S/N), in 1 slice, 8 diffusion-weighted images with b values between 56 and 3970 s/mm2 were obtained with S/N ratios of at least 18. As a first approximation, biexponential analysis of diffusion-weighted signal attenuation in this slice resulted in values of 0.54 for Ffas...