Brain structures

Brain structure below the thalamus and main portion of the ventral region of the diencephalon, controlling homeostatic and nonhomeostatic basic body and brain functions, including circadian and feeding rhythms, energy metabolism, thermogenesis, sympathoadrenal, and neuroendocrine outflow (secretion of hormones by the pituitary gland), behavioral state and memory functions. 

Collection of interconnected subcortical and cortical brain structures (including hypothalamus, amygdala, and hippocampus) integrating multimodal intero- and exteroceptive information to produce coherent neuroendocrine and behavioral output, and to support memory functions. 

In Chapter 43 the incorporation of expertise and experience in data analysis by means of expert systems is described. The knowledge acquisition bottleneck and the brittleness of domain expertise are, however, the major drawbacks in the development of expert systems. This has stimulated research on alternative techniques. Artificial neural networks (ANN) were first developed as a model of the human brain structure. The computerized version turned out to be suitable for performing tasks that are considered to be difficult to solve by classical techniques. 

Stephan H., Baron, G. and Frahm, H. (1982). Comparison of brain structure volumes in Insectivora and Primates, II Accessory olfactory bulb. J Himforsch 23, 575-591. 

McGinty, D. Szymusiak, R. (2001). Brain structures and mechanisms involved in the generation of NREM sleep focus on the preoptic hypothalamus. Sleep Med. 

Figure 2.1 Schematic of the rat brain (sagittal section) showing the approximate location of important brain structures controlling wakefulness and REM sleep. Abbreviations AH, anterior hypothalamus BF, basal forebrain DL pons, dorsolateral pons (rapid eye movement sleep control area) M-RA, Magoun/Rhines inhibitory area in the ventral medulla PH, posterior hypothalamus.

Although sleep and wakefulness are global states, specific brain structures are known to be involved in their regulation. These sites include areas within the brainstem, hypothalamus, and the thalamus, and Glu plays an active role in the control of sleep and waking in these areas. 

Neuropeptide S (NPS) is a recently discovered bioactive peptide that has emerged as a new signaling molecule in the complex circuitry that modulates sleep-wakefulness and anxiety-like behavior. The peptide precursor is expressed most prominently in a novel nucleus located in the perilocus coeruleus, a brain structure with well-defined functions in arousal, stress, and anxiety. NPS was also found to induce anxiolytic-like behavior in a battery of four different tests of innate responses to stress. Infusion of NPS potently increases wakefulness and suppresses non-REM (NREM) and REM sleep (Xu et al, 2004). NPS binds to a G-protein-coupled receptor, the NPS receptor, with nanomolar affinity activation of the receptor mobilizes intracellular calcium. The NPS receptor is expressed throughout the brain, particularly in regions relevant to the modulation of sleep and waking, in the tuberomammillary region, lateral hypothalamus, and medial thalamic nuclei. 

Limbic system A network of brain structures involved in the regulation of a number of behavioural functions. 

Michel Morange Yes, but you have another mutation in another gene which is involved in dopamine metabolism which affects the same brain structure, and which gives rise to exactly the same problems with maternal behaviour. So it s an argument to show that you have nothing specific with maternal behaviour but something specific with one brain substructure. 

The geneticist and ethologist, Hans-Peter Lipp, informs me that he has found substantial changes in the brain structure of laboratory mice released into the wild under the pressure of natural selection within four generations (Lipp, 2000). 

Berl, S. and Clarke, D. D. Introduction. In S. Berl, D. D. Clarke andD. Schneider (eds),Metabolic Compartmentation and Neurotransmission Relation to Brain Structure and Function. New York Plenum Press, 1975, pp. xiii-xvii. 

Morphometric analysis utilizing computer assisted tomography (CAT) or magnetic resonance imaging (MRI) to reveal brain structure ... 

The amygdala is perhaps the best-studied, and most strongly implicated, brain structure in anxiety and fear. Electrical stimulation of the amygdala produces fear-like behavioral and physiological responses in animals, and increases the suggestive experience of fear in human subjects. Additionally, amygdala stimulation leads to corticosterone secretion and HPA-axis activation in animals, probably via outputs to the hypothalamus and the bed nucleus of the stria terminalis. It has been suggested... 

Mann, J. J. and Arango, V. Abnormalities of brain structure and function in mood disorders. In Neurobiology of Mental Illness. Ed. Bunney, B. S. New York Oxford University Press,... 

Finite resolution and partial volume effects. Although this can occur in other areas of imaging such as MRS, it is particularly an issue for SPECT and PET because of the finite resolution of the imaging instruments. Resolution is typically imaged as the response of the detector crystal and associated electron to the point or line source. These peak in the center and fall off from a point source, for example, in shapes that simulate Gaussian curves. These are measures of the ability to resolve two points, e.g. two structures in a brain. Because brain structures, in particular, are often smaller than the FWHM for PET or SPECT, the radioactivity measured in these areas is underestimated both by its small size (known as the partial volume effect), but also spillover from adjacent radioactivity... 

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