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Brain Regions (brain + regions)
Kinds of Brain Regions Selected AbstractsPalatable High-Energy Diet Decreases the Expression of Cannabinoid Type 1 Receptor Messenger RNA in Specific Brain Regions in the RatJOURNAL OF NEUROENDOCRINOLOGY, Issue 12 2009E. Timofeeva In laboratory rodents, a palatable high-energy diet (PHED) is usually consumed in a higher quantity than a standard laboratory diet, leading to the development of an obese phenotype. The central effects of PHED are not fully understood. Nonetheless, the long-term consumption of PHED can decrease cannabinoid type 1 receptor (CB1R) protein density in particular brain regions. However, little is known about the diet-dependent regulation of the brain expression of CB1R mRNA. The present study aimed to investigate the effects of the long-term consumption of PHED and short-term (12 h) food deprivation on the brain expression of CB1R mRNA. For 13 weeks, rats were fed a standard laboratory chow or PHED presented as a free choice of chow, shortcake biscuits and pork spread. In total, the food intake of PHED rats was higher than that of chow-fed animals. Expectedly, PHED rats demonstrated higher body weight than chow-fed animals. The difference in body weight between PHED- and chow-fed rats was as result of the fat but not the lean mass. PHED-fed rats had significantly higher plasma levels of leptin and insulin and significantly higher levels of expression of suppressor of cytokine signalling 3 (SOCS-3) in the arcuate hypothalamic nucleus. The long-term consumption of PHED significantly decreased the levels of CB1R mRNA expression in the cingulate (Cg) cortex, ventromedial hypothalamic nucleus and the descending/autonomic divisions of the parvocellular hypothalamic nucleus (PVH), the ventrolateral parvocellular PVH and, to a lesser extent, the dorsomedial parvocellular PVH. Acute food deprivation decreased the levels of CB1R transcript in the Cg and ventrolateral parvocellular PVH. Altogether, the present results demonstrate that long-term PHED leads to an increase in the hypothalamic expression of SOCS-3 mRNA and a decrease in expression of CB1R mRNA in the Cg cortex and specific hypothalamic regions. [source] Recruitment of Additional Brain Regions to Accomplish Simple Motor Tasks in Chronic Alcohol-Dependent PatientsALCOHOLISM, Issue 6 2010Mitchell H. Parks Background:, Chronic alcohol-dependent patients (ALC) exhibit neurocognitive impairments attributed to alcohol-induced fronto-cerebellar damage. Deficits are typically found in complex task performance, whereas simple tasks may not be significantly compromised, perhaps because of little understood compensatory changes. Methods:, We compared finger tapping with either hand at externally paced (EP) or maximal self-paced (SP) rates and concomitant brain activation in ten pairs of right-hand dominant, age-, and gender-matched, severe, uncomplicated ALC and normal controls (NC) using functional magnetic resonance imaging (fMRI). Results:, Mean tapping rates were not significantly different in ALC and NC for either task, but SP tapping variances were greater in ALC for both hands. SP tapping was more rapid with dominant hand (DH) than non-dominant hand (NDH) for both groups. EP and SP tapping with the non-dominant hand demonstrated significantly more activation in ALC than NC in the pre and postcentral gyri, inferior frontal gyrus, inferior parietal lobule, and the middle temporal gyrus. Areas activated only by ALC (not at all by NC) during NDH tapping included the inferior frontal gyrus, middle temporal gyrus, and postcentral gyrus. There were no significant group activation differences with DH tapping. No brain regions activated more in NC than ALC. SP tapping in contrast to EP activated fronto-cerebellar networks in NC, including postcentral gyrus, anterior cingulate, and the anterior lobe and vermis of the cerebellum, but only parietal precuneus in ALC. Conclusions:, These findings with NDH finger tapping support previous reports of neurocognitive inefficiencies in ALC. Inferior frontal activation with EP in ALC, but not in NC, suggests engagement of regions needed for planning, organization, and impulse regulation; greater contralateral parietal lobe activation with SP in ALC may reflect right hemispheric impairments in visuospatial performance. Contrasting brain activation during SP and EP suggests that ALC may not have enlisted a fronto-cerebellar network as did NC but rather employed a higher order planning mode by recruiting parietal lobe functions to attain normal mean finger tapping rates. Elucidation of the compensatory neural mechanisms that allow near normal performance by ALC on simple tasks can inform functional rehabilitation of patients in recovery. [source] Ethanol-Sensitive Brain Regions in Rat and Mouse: A Cartographic Review, Using Immediate Early Gene ExpressionALCOHOLISM, Issue 6 2009Catherine Vilpoux Background:, Ethanol addiction has been conceptualized as a progression from occasional, impulsive use to compulsive behavior. Ethanol-dependence is a chronic pathology with repeated cycles of withdrawal, craving, and relapse. Specific molecular and cellular mechanisms underlie these transition stages. Methods:, This review aimed at elucidating whether there are also adaptations in the pattern of brain regions responding to ethanol. This paper reviews the evidence in rodents for activation of specific brain regions, assessed by induction of IEG expression, following acute and chronic ethanol exposure. Results:, The review sheds light on the specific patterns of response in regions of the brain to different types of ethanol exposure and shows that activation of specific brain regions may occur in particular phases of the development of ethanol addiction. Some brain regions respond consistently following acute or chronic treatments or withdrawal: the prefrontal cortex; nucleus accumbens; lateral septum; hippocampus; perioculomotor urocortin-containing cells population (pIIIu), also known as Edinger-Westphal nucleus; central nucleus of the amygdale; and the paraventricular nucleus of hypothalamus. The two last brain areas are particularly activated by relapse-inducing stressors. It is of interest that the amygdala, hippocampus, and prefrontal cortex, which belong to the reward system, are activated by cue-induced relapse to ethanol self-administration in rodents and humans, while activation of these regions is reversed with anticraving compounds. Following chronic exposure, IEG induction desensitizes while withdrawal reactivates these regions. Discussion:, Some responding regions are implicated in reward related processes (VTA, extended amygdala, hypothalamus, hippocampus, prelimbic cortex, ventral part of lateral septum) and some others in aversive-related processes (area postrema, nucleus of solitary tract). Conclusion:, A better understanding of the neural circuits affected by ethanol and their adaptations during the development of ethanol addiction will provide new opportunities for developing appropriate therapies. [source] Imaging of Language-Related Brain Regions in Detoxified AlcoholicsALCOHOLISM, Issue 6 2009Sandra Chanraud-Guillermo Background:, Neuroimaging studies showed clear evidence of alcoholism-related damage to the frontal lobes and cerebellum. Although these regions have been involved in language processing, language skills are relatively spared in alcoholics. Here, we aimed at identifying neural substrates associated with the preserved mechanisms of language processing in alcoholics. We hypothesized that alcoholics would show a different pattern of neural activity compared with the controls. Methods:, Alcoholic and nonalcoholic subjects performed an auditory language task while receiving a functional magnetic resonance imaging (fMRI) scan in a 1.5 T magnet. This task has been previously shown to solicit the comprehension processing in healthy controls, with reliable fMRI response in the left frontal and temporal/parietal lobes. Results:, Behavioral results showed comparable performance (error rates, response time) between the alcoholics and the matched controls. However, analysis of the functional data revealed that the alcoholics exhibited greater fMRI response in the left middle frontal gyrus (pars triangularis), the right superior frontal gyrus, and the cerebellar vermis relative to the controls. Conclusions:, These findings suggest that frontocerebellar neural activity, supporting the comprehension processing of the auditory language task, may require compensatory mechanisms in alcoholics in order to maintain the same level of performance as the controls. [source] Abstinence From Moderate Alcohol Self-Administration Alters Progenitor Cell Proliferation and Differentiation in Multiple Brain Regions of Male and Female P RatsALCOHOLISM, Issue 1 2009Jun He Background:, Acute and chronic ethanol exposure has been found to decrease hippocampal neurogenesis, reduce dendritic differentiation of new neurons, and increase cell death. Interestingly, abstinence from such treatment increases hippocampal neurogenesis and microglial genesis across several brain regions. The goal of the current investigation was to study cellular alterations on neuro- and cell-genesis during abstinence following alcohol self-administration using alcohol-preferring rats (P rats). Methods:, Male and female P rats were given the choice of drinking 10% alcohol in water or pure water for 7 weeks. Social interaction behavioral assessments were conducted at 5 hours upon removal of alcohol, followed by bromo-deoxyuridine (BrdU, 150 mg/kg × 1/d × 14 d) injections to label proliferating cells. Animals were then killed 4 weeks later to conduct immunohistochemical and confocal analyses using antibodies against BrdU and other phenotypic markers (NeuN for mature neurons; Iba-1 for microglia; GFAP for astrocytes; and NG2 for oligodendrocyte progenitors). Results:, Mild alcohol withdrawal anxiety was detected by reduction in social interactions. The number of hippocampal BrdU+ cells was increased approximately 50% during alcohol abstinence (26 ± 2.8 in controls vs. 39 ± 4 in alcohol group). BrdU+ cells were also increased in the substantia nigra (SN) approximately 65% in the alcohol abstinent group (12 ± 1 in controls vs. 19 ± 1.5 in alcohol group). No gender differences were found. Confocal analyses indicated that approximately 75% of co-localization of BrdU+ cells with NeuN in the hippocampal dentate gyrus (DG) resulting a net increase in neurogenesis in the alcohol abstinent group compared to controls. In cingulum, greater proportion of BrdU+ cells were co-localized with NG2 in the alcohol abstinent group indicating increased differentiation toward oligodendrocyte progenitors in both genders. However, the phenotype of the BrdU+ cells in SN and other brain regions were not identified by NeuN, Iba-1, GFAP, or NG2 suggesting that these BrdU+ cells probably remain in a nondifferentiated stage. Conclusions:, These data indicate that abstinence from moderate alcohol drinking increases hippocampal neurogenesis, cingulate NG2 differentiation, and SN undifferentiated cell proliferation in both males and females. Such cellular alteration during abstinence could contribute to the spontaneous partial restoration of cognitive deficits upon sobriety. [source] Oxidative Stress Alters Creatine Kinase System in Serum and Brain Regions of Polychlorinated Biphenyl (Aroclor 1254)-Exposed Rats: Protective Role of MelatoninBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2009Prabhu Venkataraman Creatine kinase plays a key role in energy metabolism of nervous tissue and might be one of the targets for reactive oxygen species. Melatonin, an indoleamine, plays an important role in neurodegenerative diseases as an antioxidant and neuroprotector. The objective of the present study was to investigate the protective role of melatonin on polychlorinated biphenyl (Aroclor 1254)-induced oxidative stress and the changes in creatine kinase activity in brain regions of adult rats. Group I: rats were intraperitoneally (i.p.) administered with corn oil (vehicle) for 30 days. Group II: rats injected i.p. with Aroclor 1254 at 2 mg/kg body weight (bw)/day for 30 days. Groups III and IV: rats i.p. received melatonin (5 or 10 mg/kg bw/day) simultaneously with Aroclor 1254 for 30 days. After 30 days, rats were killed and the brain regions were dissected to cerebral cortex, cerebellum and hippocampus. Lipid peroxidation, hydroxyl radical and hydrogen peroxide (H2O2) levels were determined. The activity of creatine kinase was assayed in serum and brain regions, and its isoenzymes in serum were separated electrophoretically. Activity of creatine kinase was decreased while an increase in H2O2, hydroxyl radical and lipid peroxidation was observed in brain regions of polychlorinated biphenyl-treated rats. Also polychlorinated biphenyl exposure showed a significant increase in serum creatine kinase level and its isoforms such as BB-creatine kinase, MB-creatine kinase, and MM-creatine kinase. Administration of melatonin prevented these alterations induced by polychlorinated biphenyl by its free radical scavenging mechanism. Thus, polychlorinated biphenyl alters creatine kinase activity by inducing oxidative stress in brain regions, which can be protected by melatonin. [source] A comparison of five fMRI protocols for mapping speech comprehension systemsEPILEPSIA, Issue 12 2008Jeffrey R. Binder Summary Aims:, Many fMRI protocols for localizing speech comprehension have been described, but there has been little quantitative comparison of these methods. We compared five such protocols in terms of areas activated, extent of activation, and lateralization. Methods:, fMRI BOLD signals were measured in 26 healthy adults during passive listening and active tasks using words and tones. Contrasts were designed to identify speech perception and semantic processing systems. Activation extent and lateralization were quantified by counting activated voxels in each hemisphere for each participant. Results:, Passive listening to words produced bilateral superior temporal activation. After controlling for prelinguistic auditory processing, only a small area in the left superior temporal sulcus responded selectively to speech. Active tasks engaged an extensive, bilateral attention, and executive processing network. Optimal results (consistent activation and strongly lateralized pattern) were obtained by contrasting an active semantic decision task with a tone decision task. There was striking similarity between the network of brain regions activated by the semantic task and the network of brain regions that showed task-induced deactivation, suggesting that semantic processing occurs during the resting state. Conclusions:, fMRI protocols for mapping speech comprehension systems differ dramatically in pattern, extent, and lateralization of activation. Brain regions involved in semantic processing were identified only when an active, nonlinguistic task was used as a baseline, supporting the notion that semantic processing occurs whenever attentional resources are not controlled. Identification of these lexical-semantic regions is particularly important for predicting language outcome in patients undergoing temporal lobe surgery. [source] Modulation of temporally coherent brain networks estimated using ICA at rest and during cognitive tasksHUMAN BRAIN MAPPING, Issue 7 2008Vince D. Calhoun Abstract Brain regions which exhibit temporally coherent fluctuations, have been increasingly studied using functional magnetic resonance imaging (fMRI). Such networks are often identified in the context of an fMRI scan collected during rest (and thus are called "resting state networks"); however, they are also present during (and modulated by) the performance of a cognitive task. In this article, we will refer to such networks as temporally coherent networks (TCNs). Although there is still some debate over the physiological source of these fluctuations, TCNs are being studied in a variety of ways. Recent studies have examined ways TCNs can be used to identify patterns associated with various brain disorders (e.g. schizophrenia, autism or Alzheimer's disease). Independent component analysis (ICA) is one method being used to identify TCNs. ICA is a data driven approach which is especially useful for decomposing activation during complex cognitive tasks where multiple operations occur simultaneously. In this article we review recent TCN studies with emphasis on those that use ICA. We also present new results showing that TCNs are robust, and can be consistently identified at rest and during performance of a cognitive task in healthy individuals and in patients with schizophrenia. In addition, multiple TCNs show temporal and spatial modulation during the cognitive task versus rest. In summary, TCNs show considerable promise as potential imaging biological markers of brain diseases, though each network needs to be studied in more detail. Hum Brain Mapp, 2008. © 2008 Wiley-Liss, Inc. [source] Ethanol neurotoxicity and dentate gyrus developmentCONGENITAL ANOMALIES, Issue 3 2008Takanori Miki ABSTRACT Maternal alcohol ingestion during pregnancy adversely affects the developing fetus, often leading to fetal alcohol syndrome (FAS). One of the most severe consequences of FAS is brain damage that is manifested as cognitive, learning, and behavioral deficits. The hippocampus plays a crucial role in such abilities; it is also known as one of the brain regions most vulnerable to ethanol-induced neurotoxicity. Our recent studies using morphometric techniques have further shown that ethanol neurotoxicity appears to affect the development of the dentate gyrus in a region-specific manner; it was found that early postnatal ethanol exposure causes a transitory deficit in the hilus volume of the dentate gyrus. It is strongly speculated that such structural modifications, even transitory ones, appear to result in developmental abnormalities in the brain circuitry and lead to the learning disabilities observed in FAS children. Based on reports on possible factors deciding ethanol neurotoxicity to the brain, we review developmental neurotoxicity to the dentate gyrus of the hippocampal formation. [source] Turner syndrome: Neuroimaging findings: Structural and functionalDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 4 2009Ronan Mullaney Abstract Neuroimaging studies of Turner syndrome can advance our understanding of the X chromosome in brain development, and the modulatory influence of endocrine factors. There is increasing evidence from neuroimaging studies that TX individuals have significant differences in the anatomy, function, and metabolism of a number of brain regions; including the parietal lobe; cerebellum, amygdala, hippocampus; and basal ganglia; and perhaps differences in "connectivity" between frontal and parieto-occipital regions. Finally, there is preliminary evidence that genomic imprinting, sex hormones and growth hormone have significant modulatory effects on brain maturation in TS. © 2009 Wiley-Liss, Inc. Dev Disabil Res Rev 2009;15:279,283. [source] Environmental complexity and central nervous system development and functionDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2004Mark H. Lewis Abstract Environmental restriction or deprivation early in development can induce social, cognitive, affective, and motor abnormalities similar to those associated with autism. Conversely, rearing animals in larger, more complex environments results in enhanced brain structure and function, including increased brain weight, dendritic branching, neurogenesis, gene expression, and improved learning and memory. Moreover, in animal models of CNS insult (e.g., gene deletion), a more complex environment has attenuated or prevented the sequelae of the insult. Of relevance is the prevention of seizures and attenuation of their neuropathological sequelae as a consequence of exposure to a more complex environment. Relatively little attention, however, has been given to the issue of sensitive periods associated with such effects, the relative importance of social versus inanimate stimulation, or the unique contribution of exercise. Our studies have examined the effects of environmental complexity on the development of the restricted, repetitive behavior commonly observed in individuals with autism. In this model, a more complex environment substantially attenuates the development of the spontaneous and persistent stereotypies observed in deer mice reared in standard laboratory cages. Our findings support a sensitive period for such effects and suggest that early enrichment may have persistent neuroprotective effects after the animal is returned to a standard cage environment. Attenuation or prevention of repetitive behavior by environmental complexity was associated with increased neuronal metabolic activity, increased dendritic spine density, and elevated neurotrophin (BDNF) levels in brain regions that are part of cortical,basal ganglia circuitry. These effects were not observed in limbic areas such as the hippocampus. MRDD Research Reviews 2004;10:91,95. © 2004 Wiley-Liss, Inc. [source] The neuroanatomy and neuroendocrinology of fragile X syndromeDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2004David Hessl Abstract Fragile X syndrome (FXS), caused by a single gene mutation on the X chromosome, offers a unique opportunity for investigation of gene,brain,behavior relationships. Recent advances in molecular genetics, human brain imaging, and behavioral studies have started to unravel the complex pathways leading to the cognitive, psychiatric, and physical features that are unique to this syndrome. In this article, we summarize studies focused on the neuroanatomy and neuroendocrinology of FXS. A review of structural imaging studies of individuals with the full mutation shows that several brain regions are enlarged, including the hippocampus, amygdala, caudate nucleus, and thalamus, even after controlling for overall brain volume. These regions mediate several cognitive and behavioral functions known to be aberrant in FXS such as memory and learning, information and sensory processing, and social and emotional behavior. Two regions, the cerebellar vermis, important for a variety of cognitive tasks and regulation of motor behavior, and the superior temporal gyrus, involved in processing complex auditory stimuli, are reported to be reduced in size relative to controls. Functional imaging, typically limited to females, has emphasized that individuals with FXS do not adequately recruit brain regions that are normally utilized by unaffected individuals to carry out various cognitive tasks, such as arithmetic processing or visual memory tasks. Finally, we review a number of neuroendocrine studies implicating hypothalamic dysfunction in FXS, including abnormal activation of the hypothalamic,pituitary,adrenal (HPA) axis. These studies may help to explain the abnormal stress responses, sleep abnormalities, and physical growth patterns commonly seen in affected individuals. In the future, innovative longitudinal studies to investigate development of neurobiologic and behavioral features over time, and ultimately empirical testing of pharmacological, behavioral, and even molecular genetic interventions using MRI are likely to yield significant positive changes in the lives of persons with FXS, as well as increase our understanding of the development of psychiatric and learning problems in the general population. MRDD Research Reviews 2004;10:17,24. © 2004 Wiley-Liss, Inc. [source] Fiber tracking using magnetic resonance diffusion tensor imaging and its applications to human brain developmentDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2003Richard Watts Abstract Diffusion tensor imaging is unique in its ability to noninvasively visualize white matter fiber tracts in the human brain in vivo. Diffusion is the incoherent motion of water molecules on a microscopic scale. This motion is itself dependent on the micro-structural environment that restricts the movement of the water molecules. In white matter fibers there is a pronounced directional dependence on diffusion. With white matter fiber tracking or tractography, projections among brain regions can be detected in the three-dimensional diffusion tensor dataset according to the directionality of the fibers. Examples of developmental changes in diffusion, tracking of major fiber tracts, and examples of how diffusion tensor tractography and functional magnetic resonance imaging can be combined are provided. These techniques are complimentary and allow both the identification of the eloquent areas of the brain involved in specific functional tasks, and the connections between them. The noninvasive nature of magnetic resonance imaging will allow these techniques to be used in both longitudinal developmental and diagnostic studies. An overview of the technique and preliminary applications are presented, along with its current limitations. MRDD Research Reviews 2003;9:168,177. © 2003 Wiley-Liss, Inc. [source] The expression of Scratch genes in the developing and adult brainDEVELOPMENTAL DYNAMICS, Issue 9 2006Faustino Marín Abstract The Scratch genes belong to the Snail superfamily of zinc-finger transcription factors present in the metazoa, represented in mammals by the Scratch1 and Scratch2 genes. We have analyzed the expression of these genes in the brain of mice at developmental stages between 9.5 days-post-coitum to adulthood. Both genes are expressed in the mantle layer of the neuroepithelium at mid-gestational stages in all regions except for the region corresponding to the V2 interneuron column, which lacked Scratch2 transcripts. From perinatal to adult stages, the expression patterns of the two genes differ. Scratch1 remains strongly expressed in almost all brain regions, although it is not found in some ventral structures such as motor nuclei and hypothalamic regions. In contrast, Scratch2 expression progressively diminishes and virtually no expression can be detected in the adult brain. Nevertheless, strong expression of Scratch2 is retained in the postnatal cortical subventricular zone, in the inner part of the cerebellar external granular layer, and in the glial cells of the adult vomeronasal nerve. Developmental Dynamoics 235:2586,2591, 2006. © 2006 Wiley-Liss, Inc. [source] cadherin-6 Message expression in the nervous system of developing zebrafishDEVELOPMENTAL DYNAMICS, Issue 1 2006Qin Liu Abstract Cadherins are cell surface adhesion molecules that play important roles in development of a variety of tissues including the nervous system. In this study, we analyzed expression pattern of cadherin-6, a member of the type II cadherin subfamily, in the embryonic zebrafish nervous system using in situ hybridization methods. cadherin-6 message is first expressed by the neural keel, then by restricted regions in the brain and spinal cord. cadherin-6 expression in the brain transiently delineates specific brain regions. In the peripheral nervous system, cadherin-6 message is expressed by the neurogenic placodes and the dorsal root ganglia. As development proceeds, cadherin-6 expression domain and/or expression levels increased in the embryonic nervous system. Our results show that cadherin-6 expression in the zebrafish developing nervous system is both spatially and temporally regulated, implicating a role for cadherin-6 in the formation of these nervous structures. Developmental Dynamics 235:272,278, 2006. © 2005 Wiley-Liss, Inc. [source] Lesion-induced neurogenesis in the hypothalamus is involved in behavioral recovery in adult ring dovesDEVELOPMENTAL NEUROBIOLOGY, Issue 6 2006Gang Chen Abstract Although neurogenesis in the brain of adult vertebrates is region dependent, lesion induces generation of new neurons in non-neurogenic brain regions. These findings raise the question of the role of new neurons in brain repair and functional recovery. We addressed this question by applying previous observations that electrolytic lesion induced neurogenesis in the ventromedial nucleus (VMN) of the hypothalamus in adult ring doves. Such lesions disrupted the male's courtship behavior, which could be reinstated after rehabilitation with a female. We investigated whether lesion-induced newborn neurons in the VMN facilitate the recovery of courtship behavior in the lesioned birds. We conducted systematic observations of cytological, morphological, and neuroanatomical changes in the lesioned VMN, and concurrently we monitored behavioral changes. Using a multitude of specific cell markers, we found a well-circumscribed cellular zone that proliferated actively. This highly proliferative zone initially appeared along the periphery of the lesion site, where cells had high levels of expression of neuronal, glial, and neurovascular markers. As newborn neurons matured at the lesion site, the necrosis gradually decreased, whereas a downsized proliferative zone relocated to a region ventral to the VMN. Some of the mature neurons were found to project to the midbrain vocal nuclei. Restoration of these projection neurons coincided with the recovery of courtship vocalization. Finally, we found that a social factor, that is, when the male doves were cohoused with a mate, facilitated neurogenesis and behavioral recovery. These results suggest that lesion-induced neurogenesis contributes to behavioral recovery in adult animals. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] Immediate early gene (ZENK, Arc) expression in the auditory forebrain of female canaries varies in response to male song qualityDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2005Stefan Leitner Abstract In male songbirds, the song control pathway in the forebrain is responsible for song production and learning, and in females it is associated with the perception and discrimination of male song. However, experiments using the expression of immediate early genes (IEGs) reveal the activation of brain regions outside the song control system, in particular the caudomedial nidopallium (NCM) and the caudomedial mesopallium (CMM). In this study on female canaries, we investigate the role of these two regions in relation to playback of male songs of different quality. Male canaries produce elaborate songs and some contain syllables with a more complex structure (sexy syllables) that induce females to perform copulation solicitation displays (CSD) as an invitation to mate. Females were first exposed to playback of a range of songs of different quality, before they were finally tested with playback of songs containing either sexy or nonsexy syllables. We then sectioned the brains and used in situ hybridization to reveal brain regions that express the IEGs ZENK or Arc. In CMM, expression of ZENK mRNA was significantly higher in females that last heard sexy syllables compared to those that last heard nonsexy syllables, but this was not the case for NCM. Expression of Arc mRNA revealed no differences in either CMM or NCM in both experimental groups. These results provide evidence that in female canaries CMM is involved in female perception and discrimination of male song quality through a mechanism of memory reconsolidation. The results also have further implications for the evolution of complex songs by sexual selection and female choice. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 [source] Evidence for species differences in the pattern of androgen receptor distribution in relation to species differences in an androgen-dependent behaviorDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2002Brian K. Shaw Abstract Chickens (Gallus gallus domesticus) and Japanese quail (Coturnix japonica), two closely related gallinaceous bird species, exhibit a form of vocalization,crowing,which differs between the species in two components: its temporal acoustic pattern and its accompanying postural motor pattern. Previous work utilizing the quail-chick chimera technique demonstrated that the species-specific characteristics of the two crow components are determined by distinct brain structures: the midbrain confers the acoustic pattern, and the caudal hindbrain confers the postural pattern. Crowing is induced by androgens, acting directly on androgen receptors. As a strategy for identifying candidate neurons in the midbrain and caudal hindbrain that could be involved in crow production, we performed immunocytochemistry for androgen receptors in these brain regions in both species. We also investigated midbrain-to-hindbrain vocal-motor projections. In the midbrain, both species showed prominent androgen receptor immunoreactivity in the nucleus intercollicularis, as had been reported in previous studies. In the caudal hindbrain, we discovered characteristic species differences in the pattern of androgen receptor distribution. Chickens, but not quail, showed strong immunoreactivity in the tracheosyringeal division of the hypoglossal nucleus, whereas quail, but not chickens, possessed strong immunoreactivity in a region of the ventrolateral medulla. Some of these differences in hindbrain androgen receptor distribution may be related to the species differences in the postural component of crowing behavior. The results of the present study imply that the spatial distribution of receptor proteins can vary even between closely related species. Such variation in receptor distribution could underlie the evolution of species differences in behavior. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 203,220, 2002 [source] Regional Fos expression induced by morphine withdrawal in the 7-day-old ratDEVELOPMENTAL PSYCHOBIOLOGY, Issue 7 2009Anika A. McPhie Abstract Human infants are often exposed to opiates chronically but the mechanisms by which opiates induce dependence in the infant are not well studied. In the adult the brain regions involved in the physical signs of opiate withdrawal include the periaqueductal gray area, the locus coeruleus, amygdala, ventral tegmental area, nucleus accumbens, hypothalamus, and spinal cord. Microinjection studies show that many of these brain regions are involved in opiate withdrawal in the infant rat. Our goal here was to determine if these regions become metabolically active during physical withdrawal from morphine in the infant rat as they do in the adult. Following chronic morphine or saline treatment, withdrawal was precipitated in 7-day-old pups with the opiate antagonist naltrexone. Cells positive for Fos-like immunoreactivity were quantified within select brain regions. Increased Fos-like labeled cells were found in the periaqueductal gray, nucleus accumbens, locus coeruleus, and spinal cord. These are consistent with other studies showing that the neural circuits underlying the physical signs of opiate withdrawal are similar in the infant and adult. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 544,552, 2009. [source] The effects of selective breeding for differential rates of 50-kHz ultrasonic vocalizations on emotional behavior in ratsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2009Jeffrey Burgdorf Abstract Fifty-kHz ultrasonic vocalizations have previously been shown to be positively correlated with reward and appetitive social behavior in rats, and to reflect a positive affective state. In this study, rats selectively bred for high and low rates of 50-kHz vocalizations as juveniles were tested as adults in a battery of behavioral tests for social/emotional behaviors. We found that animals selectively bred for high rates of 50-kHz vocalizations exhibited more crosses into the center area of the open field apparatus, were more likely to show a preference for a dilute sucrose solution (.8%) compared to tap water, and were less aggressive than randomly bred animals. Conversely, animals bred for low rates of 50-kHz calls produced more fecal boli during both open field testing and "tickling" stimulation, and made less contact with conspecifics in a social interaction test compared to randomly bred animals. We also observed that low line rats have elevated brain levels of cholecystokinin (CCK) in the cortex, which is consistent with literature showing that CCK content in the cortex is positively correlated with rates of aversive 22-kHz USVs. Conversely, high line animals had elevated levels of met-enkephalin in several brain regions, which is consistent with the role of endogenous-opioids in the generation 50-kHz USVs and positive affect. These results suggest that animals bred for high rates of 50-kHz may show a stress resilient phenotype, whereas low line rats may show a stress prone phenotype. As such these animals could provide novel insights into the neurobiology of emotion. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 51: 34,46, 2009 [source] Perceived quality of maternal care in childhood and structure and function of mothers' brainDEVELOPMENTAL SCIENCE, Issue 4 2010Pilyoung Kim Animal studies indicate that early maternal care has long-term effects on brain areas related to social attachment and parenting, whereas neglectful mothering is linked with heightened stress reactivity in the hippocampus across the lifespan. The present study explores the possibility, using magnetic resonance imaging, that perceived quality of maternal care in childhood is associated with brain structure and functional responses to salient infant stimuli among human mothers in the first postpartum month. Mothers who reported higher maternal care in childhood showed larger grey matter volumes in the superior and middle frontal gyri, orbital gyrus, superior temporal gyrus and fusiform gyrus. In response to infant cries, these mothers exhibited higher activations in the middle frontal gyrus, superior temporal gyrus and fusiform gyrus, whereas mothers reporting lower maternal care showed increased hippocampal activations. These findings suggest that maternal care in childhood may be associated with anatomy and functions in brain regions implicated in appropriate responsivity to infant stimuli in human mothers. [source] On the role of cortical glutamate inobsessive-compulsive disorder and attention-deficit hyperactivity disorder, two phenomenologically antithetical conditionsACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2000Maria L. CarlssonArticle first published online: 24 DEC 200 Objective: The objective of the present study was to compare the phenomenology and pathophysiology of obsessive-compulsive disorder (OCD) and attention-deficit hyperactivity disorder/deficits in attention, motor control and perception (ADHD/DAMP). Method: Through detailed studies of the literature on OCD and ADHD/DAMP the phenomenology of these two conditions is compared, and possible underlying pathophysiological mechanisms involving interactions between glutamate, dopamine, serotonin and acetylcholine are discussed, with emphasis on OCD. The present paper also discusses possible mechanisms of action for current pharmacological treatments of OCD and ADHD, as well as possible future treatment strategies for these disorders. Results: OCD and ADHD/DAMP are common neuropsychiatric conditions which in many regards appear to be each other's antipodes with respect to clinical manifestations, associated personality traits and brain biochemistry, notably prefrontal cortical glutamate activity. Future pharmacological treatments of these disorders may involve manipulations with glutamate, dopamine D1, serotonin 2A and nicotine receptors. Conclusion: It appears that OCD is a hyperglutamatergic and ADHD a hypoglutamatergic condition, with prefrontal brain regions being especially affected. [source] The evolution of hippocampus volume and brain size in relation to food hoarding in birdsECOLOGY LETTERS, Issue 12 2004László Zsolt Garamszegi Abstract Food-hoarding birds frequently use spatial memory to relocate their caches, thus they may evolve a larger hippocampus in their brain than non-hoarder species. However, previous studies testing for such interspecific relationships provided conflicting results. In addition, food hoarding may be a cognitively complex task involving elaboration of a variety of brain regions, even outside of the hippocampus. Hence, specialization to food hoarding may also result in the enlargement of the overall brain. In a phylogenetic analysis of distantly related birds, we studied the interspecific association between food hoarding and the size of different brain regions, each reflecting different resolutions. After adjusting for allometric effects, the relative volume of the hippocampus and the relative size of the entire brain were each positively related to the degree of food-hoarding specialization, even after controlling for migration and brood parasitism. We also found some significant evidence for the relative volume of the telencephalon being associated with food hoarding, but this relationship was dependent on the approach we used. Hence, neural adaptation to food hoarding may favour the evolution of different brain structures. [source] Widespread axonal damage in the brain of drug abusers as evidenced by accumulation of ,-amyloid precursor protein (,-APP): an immunohistochemical investigationADDICTION, Issue 9 2006Andreas Büttner ABSTRACT Background In drug abusers, white matter changes have been described by neuroimaging analyses in different brain regions. A specific pattern of involvement or a predominance of a specific brain region could not be drawn. Aims To examine alterations of the white matter as a possible morphological substrate of the neuroimaging findings. Methods Brain specimens of 30 polydrug abusers and 20 controls were obtained at autopsy. The white matter from 11 different brain regions was analysed by means of immunohistochemistry for ,-amyloid precursor protein (,-APP), a marker of axonal damage. Findings In the white matter of polydrug abusers, ,-APP-immunopositive accumulations were increased significantly compared to controls. They were more prominent in the brains of younger drug abusers than in those of the elderly. With the exception of five cases (four polydrug abusers and one control case), there were no significant white matter changes seen on myelin-stained sections, but there was a concomitant microglial activation. Conclusions Our results show a significant axonal damage in the brains of polydrug abusers, which might represent the morphological substrate of a chronic-progressive drug-induced toxic-metabolic process. It is yet to be established if the observed changes are responsible for the alterations seen in different neuroimaging analyses and which drugs of abuse might be of major pathogenetic significance. [source] Region-specific changes in gene expression in rat brain after chronic treatment with levetiracetam or phenytoinEPILEPSIA, Issue 9 2010Bjřrnar Hassel Summary Purpose:, It is commonly assumed that antiepileptic drugs (AEDs) act similarly in the various parts of the brain as long as their molecular targets are present. A few experimental studies on metabolic effects of vigabatrin, levetiracetam, valproate, and lamotrigine have shown that these drugs may act differently in different brain regions. We examined effects of chronic treatment with levetiracetam or phenytoin on mRNA levels to detect regional drug effects in a broad, nonbiased manner. Methods:, mRNA levels were monitored in three brain regions with oligonucleotide-based microarrays. Results:, Levetiracetam (150 mg/kg for 90 days) changed the expression of 65 genes in pons/medulla oblongata, two in hippocampus, and one in frontal cortex. Phenytoin (75 mg/kg), in contrast, changed the expression of only three genes in pons/medulla oblongata, but 64 genes in hippocampus, and 327 genes in frontal cortex. Very little overlap between regions or drug treatments was observed with respect to effects on gene expression. Discussion:, We conclude that chronic treatment with levetiracetam or phenytoin causes region-specific and highly differential effects on gene expression in the brain. Regional effects on gene expression could reflect regional differences in molecular targets of AEDs, and they could influence the clinical profiles of AEDs. [source] WAG/Rij rats show a reduced expression of CB1 receptors in thalamic nuclei and respond to the CB1 receptor agonist, R(+)WIN55,212-2, with a reduced incidence of spike-wave dischargesEPILEPSIA, Issue 8 2010Clementina M. Van Rijn Summary Purpose:, Genetically epileptic WAG/Rij rats develop spontaneous absence-like seizures after 3 months of age. We used WAG/Rij rats to examine whether absence seizures are associated with changes in the expression of type-1 cannabinoid (CB1) receptors. Methods:, Receptor expression was examined by in situ hybridization and western blot analysis in various brain regions of "presymptomatic" 2-month old and "symptomatic" 8-month-old WAG/Rij rats relative to age-matched nonepileptic control rats. Furthermore, we examined whether pharmacologic activation of CB1 receptor affects absence seizures. We recorded spontaneous spike-wave discharges (SWDs) in 8-month old WAG/Rij rats systemically injected with the potent CB1 receptor agonist, R(+)WIN55,212-2 (3,12 mg/kg, s.c.), given alone or combined with the CB1 receptor antagonist/inverse agonist, AM251 (12 mg/kg, s.c.). Results:, Data showed a reduction of CB1 receptor mRNA and protein levels in the reticular thalamic nucleus, and a reduction in CB1 receptor protein levels in ventral basal thalamic nuclei of 8-month-old WAG/Rij rats, as compared with age-matched ACI control rats. In vivo, R(+)WIN55,212-2 caused a dose-dependent reduction in the frequency of SWDs in the first 3 h after the injection. This was followed by a late increase in the mean SWD duration, which suggests a biphasic modulation of SWDs by CB1 receptor agonists. Both effects were reversed or attenuated when R(+)WIN55,212-2 was combined with AM251. Discussion:, These data indicate that the development of absence seizures is associated with plastic modifications of CB1 receptors within the thalamic-cortical-thalamic network, and raise the interesting possibility that CB1 receptors are targeted by novel antiabsence drugs. [source] Monoamine variability in the chronic model of atypical absence seizuresEPILEPSIA, Issue 4 2009Eduard Bercovici Summary Purpose:, We studied the variability of the slow-spike-and-wave discharges (SSWDs) derived from AY-9944 (AY) treatment during brain development of Long-Evans hooded (LEh) rats. Methods:, Although all LEh rats received the standard dose of AY (7.5 mg/kg), we have observed an intersubject variability of the total SSWD duration at postnatal day (P) 55. Therefore, we set out to investigate the underlying brain levels of norepinephrine (NE), dopamine (DA), and serotonin (5-HT) and its metabolite (5-HIAA), as determined by high-performance liquid chromatography (HPLC) analyses from four different brain regions: thalamus (Th), frontoparietal cortex (Cx), hippocampus (Hp), and brainstem (Bs). Results:, All brains were obtained after two baseline electrocorticographic (ECoG) recordings with characteristic chronic, recurrent, bilaterally synchronous 4,6 Hz SSWD, at P 55 (336.25 ± 97.23 s/h) and P60 (494.50 ± 150.36 s) (r = 0.951, r2 = 0.904, p < 0.005, Pearson product). The thalamic NE levels and the brainstem NE, DA, and 5HT levels were all significantly correlated with baseline SSWD duration at P55 and P60 (p < 0.01, Pearson product). Conclusion:, Our data indicate that brain monoamine levels may determine the intersubject variability of SSWD duration in AY rats with chronic atypical absence seizures. [source] A comparison of five fMRI protocols for mapping speech comprehension systemsEPILEPSIA, Issue 12 2008Jeffrey R. Binder Summary Aims:, Many fMRI protocols for localizing speech comprehension have been described, but there has been little quantitative comparison of these methods. We compared five such protocols in terms of areas activated, extent of activation, and lateralization. Methods:, fMRI BOLD signals were measured in 26 healthy adults during passive listening and active tasks using words and tones. Contrasts were designed to identify speech perception and semantic processing systems. Activation extent and lateralization were quantified by counting activated voxels in each hemisphere for each participant. Results:, Passive listening to words produced bilateral superior temporal activation. After controlling for prelinguistic auditory processing, only a small area in the left superior temporal sulcus responded selectively to speech. Active tasks engaged an extensive, bilateral attention, and executive processing network. Optimal results (consistent activation and strongly lateralized pattern) were obtained by contrasting an active semantic decision task with a tone decision task. There was striking similarity between the network of brain regions activated by the semantic task and the network of brain regions that showed task-induced deactivation, suggesting that semantic processing occurs during the resting state. Conclusions:, fMRI protocols for mapping speech comprehension systems differ dramatically in pattern, extent, and lateralization of activation. Brain regions involved in semantic processing were identified only when an active, nonlinguistic task was used as a baseline, supporting the notion that semantic processing occurs whenever attentional resources are not controlled. Identification of these lexical-semantic regions is particularly important for predicting language outcome in patients undergoing temporal lobe surgery. [source] Voxel-based T2 Relaxation Rate Measurements in Temporal Lobe Epilepsy (TLE) with and without Mesial Temporal SclerosisEPILEPSIA, Issue 2 2007Susanne G. Mueller Summary:,Introduction: Quantitative measurements of T2 relaxation in the hippocampus for focus lateralization in mesial temporal lobe epilepsy (mTLE) are well established. Less is known to what degree such relaxation abnormalities also affect regions beyond the ipsilateral hippocampus. Therefore, the aim of this study was to characterize extent and distribution pattern of extrahippocampal relaxation abnormalities in TLE with (TLE-MTS) and without MRI evidence of mesial-temporal sclerosis (TLE-no). Methods: Double spin echo images (TE1/2: 20/80 ms) acquired in 24 TLE-MTS and 18 TLE-no were used to calculate relaxation rate maps. These maps were analyzed by SPM2 and by selecting regions of interest (ROI) in the hippocampus and several extrahippocampal brain regions. Results: In TLE-MTS, the results of the SPM and ROI analysis were in good agreement and showed the most severe relaxation rate decreases in the ipsilateral hippocampus but also in other ipsilateral temporal regions, orbitofrontal, and parietal regions and to a lesser degree in contralateral frontal regions. The relaxation rate decreases in TLE-no were confined to small regions in the ipsilateral anterior inferior and medial temporal lobe in the SPM analysis while ROI analysis showed additional regions in the ipsilateral hippocampus, amygdala, and anterior cingulate. Conclusion: TLE-MTS showed extensive, widespread but predominantly ipsilateral temporal and also extratemporal T2 relaxation rate decreases. In contrast, the findings of the SPM and ROI analyses in TLE-no suggested that if relaxation rate decreases are present, they are less uniform and generally milder than in TLE-MTS. This further supports the hypothesis that TLE-no is a distinct clinicopathological entity from TLE-MTS and probably heterogeneous in itself. [source] Dynamic Changes of Ictal High-Frequency Oscillations in Neocortical Epilepsy: Using Multiple Band Frequency AnalysisEPILEPSIA, Issue 2 2007Ayako Ochi Summary:,Purpose: To characterize the spatial and temporal course of ictal high-frequency oscillations (HFOs) recorded by subdural EEG in children with intractable neocortical epilepsy. Methods: We retrospectively studied nine children (four girls, five boys; 4,17 yr) who presented with intractable extrahippocampal localization-related epilepsy and who underwent extraoperative video subdural EEG (1000 Hz sampling rate) and cortical resection. We performed multiple band frequency analysis (MBFA) to evaluate the frequency, time course, and distribution of ictal HFOs. We compared ictal HFO changes before and after clinical onset and postsurgical seizure outcomes. Results: Seventy-eight of 79 seizures showed HFOs. We observed wide-band HFOs (,250Hz, ,120 electrodes) in six patients either with partial seizures alone (three patients) or with epileptic spasms (three patients). Three patients with partial seizures that secondarily generalized had wide-band HFOs (,170 Hz) before clinical onset and sustained narrow-band HFOs (60,164 Hz) with electrodecremental events after clinical onset (,28 electrodes). In four postoperatively seizure-free patients, more electrodes recorded higher-frequency HFOs inside the resection area than outside before and after clinical seizure onset. In five patients with residual seizures, electrodes recorded more HFOs that were of higher or equal frequency outside the surgical area than inside after clinical onset. Conclusion: For partial seizures alone and epileptic spasms, more electrodes recorded only wide-band HFOs; for partial seizures that secondarily generalized, fewer electrodes recorded wide-band HFOs, but in these seizures electrodes also recorded subsequent sustained narrow-band ictal HFOs. Resection of those brain regions having electrodes with ictal, higher HFOs resulted in postsurgical seizure-free outcomes. [source] | ||||||||||||||||||||||||||||||||||||||||