The effect of social defeat on tyrosine hydroxylase phosphorylation in the rat brain and adrenal gland

Tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis, is regulated acutely by protein phosphorylation and chronically by protein synthesis. No studies have systematically investigated the phosphorylation of these sites in vivo in response to stressors. We specifically investigated the phosphorylation of TH occurring within the first 24 h in response to the social defeat stress in the rat adrenal, the locus coeruleus, substantia nigra and ventral tegmental area. Five groups were investigated; home cage control (HCC), two groups that underwent social defeat (SD+) which were sacrificed either 10 min or 24 h after the end of the protocol and two groups that were put into the cage without the resident being present (SD−) which were sacrificed at time points identical to the SD+. We found at 10 min there were significant increases in serine 40 and 31 phosphorylation levels in the locus coeruleus in SD+ compared to HCC and increases in serine 40 phosphorylation levels in the substantia nigra in SD+ compared to SD−. We found at 24 h there were significant increases in serine 19 phosphorylation levels in the ventral tegmental area in SD+ compared to HCC and decreases in serine 40 phosphorylation levels in the adrenal in SD+ compared to SD−. These findings suggest that the regulation of TH phosphorylation in different catecholamine-producing cells varies considerably and is dependent on both the nature of the stressor and the time at which the response is analysed.

Application of a brain inspired model for profiling multi-view crime patterns

With the massive amount of crime data generated daily, this has put law enforcement under intensive stress. This means that law enforcement has to compete against the time to solve crime. In addition, the focus of crime investigation has been expanded from the ability to catch the criminals towards the ability to act before a crime happens (i.e pre-crime). Given such situation, creation of crime profiles is very important to law enforcement, especially in understanding the behaviours of criminals and identifying the characteristics of similar crimes. In fact, crime profiles could be used to solve similar crimes and thus pre-crime action could be conducted. In this paper, a brain inspired conceptual model is proposed and a structurally adaptive neural network is deployed for its implementation. Subsequently, the proposed model is applied for the identification and presentation of multi-view crime patterns. Such multi-view crime patterns could be useful for the construction of crime profiles. Moreover, the suitability of the proposed model in crime profiling is discussed and demonstrated through some experimental results.

Brains and bravery: little evidence of a relationship between brain size and flightiness in shorebirds

The ability of birds to perceive, assess and appropriately respond to the presence of relatively novel threats is important to their survival. We hypothesized that the cognitive capacity of birds will influence their ability for accurate response to novelty. We used brain volume as a surrogate for cognitive capacity and postulated that larger brained birds would moderate their responses when presented with a benign, frequently occurring stimulus, such as a person, because they would habituate more readily. We conducted phylogenetic generalized least square regression to investigate the relationship between brain volume and flight initiation distance (FID; the distance to which a bird can be approached before initiating escape behaviour), while controlling for confounding factors including body size (body mass and wing length) and migration status. We compared seven different models using combinations of these parameters using Akaike's information criterion to determine the best approximating model(s) explaining FID. The two best-supported models included only wing length and only body mass with Akaike weights of 0.396 and 0.311 respectively. No model including brain volume had an Akaike weight greater than 0.083 and brain volume was poorly correlated with FID in models after controlling for body mass. Thus, brain volume does not appear to strongly relate to bravery among these shorebirds.

Human brain structural change related to acute single exposure to sarin

Objective This study aimed to identify persistent morphological changes subsequent to an acute single-time exposure to sarin, a highly poisonous organophosphate, and the neurobiological basis of long-lasting somatic and cognitive symptoms in victims exposed to sarin.

Methods Thirty-eight victims of the 1995 Tokyo subway sarin attack, all of whom had been treated in an emergency department for sarin intoxication, and 76 matched healthy control subjects underwent T1-weighted and diffusion tensor magnetic resonance imaging (DTI) in 2000 to 2001. Serum cholinesterase (ChE) levels measured immediately and longitudinally after the exposure and the current severity of chronic reports in the victims were also evaluated.

Results The voxel-based morphometry exhibited smaller than normal regional brain volumes in the insular cortex and neighboring white matter, as well as in the hippocampus in the victims. The reduced regional white matter volume correlated with decreased serum cholinesterase levels and with the severity of chronic somatic complaints related to interoceptive awareness. Voxel-based analysis of diffusion tensor magnetic resonance imaging further demonstrated an extensively lower than normal fractional anisotropy in the victims. All these findings were statistically significant (corrected p < 0.05).

Interpretation Sarin intoxication might be associated with structural changes in specific regions of the human brain, including those surrounding the insular cortex, which might be related to elevated subjective awareness of internal bodily status in exposed individuals.

Underlying neurobiology and clinical correlates of mania status after subthalamic nucleus deep brain stimulation in Parkinson's Disease : a review of the literature

Deep brain stimulation (DBS) is a novel and effective surgical intervention for refractory Parkinson's disease (PD). The authors review the current literature to identify the clinical correlates associated with subthalamic nucleus (STN) DBS-induced hypomania/mania in PD patients. Ventromedial electrode placement has been most consistently implicated in the induction of STN DBS-induced mania. There is some evidence of symptom amelioration when electrode placement is switched to a more dorsolateral contact. Additional clinical correlates may include unipolar stimulation, higher voltage (>3 V), male sex, and/or early-onset PD. STN DBS-induced psychiatric adverse events emphasize the need for comprehensive psychiatric presurgical evaluation and follow-up in PD patients. Animal studies and prospective clinical research, combined with advanced neuroimaging techniques, are needed to identify clinical correlates and underlying neurobiological mechanisms of STN DBS-induced mania. Such working models would serve to further our understanding of the neurobiological underpinnings of mania and contribute valuable new insight toward development of future DBS mood-stabilization therapies.

Effect of deep brain stimulation on nucleus accumbens dopamine in a preclinicla model of antidepressant treatment-resistance

Background / Purpose: To determine if clinically effective deep brain stimulation (DBS) of neurosurgical targets for treatment-resistant depression regulates transient mesoaccumbens dopamine release in control and antidepressant-resistant animals (rats).

Main conclusion: In control rats, DBS stimulation of either the nucleus accumbens or infralimbic cortex significantly attenuated transient mesoaccumbens dopamine efflux, with nucleus accumbens DBS inducing a greater attenuation than infralimbic DBS. High frequency DBS of both targets induced long-term depression of transient accumbens dopamine release, lasting > 2hr post DBS.

Conversely, in antidepressant-resistant rats, infralimbic DBS significantly potentiated transient mesoaccumbens dopamine efflux during stimulation, but failed to induce long-lasting changes in neurotransmission. This suggests that a key mechanism of DBS for treatment-resistant depression is the regulation of dysfunctional mesoaccumbens dopamine neurotransmission.

Detection of brain conditions from evoked responses using artificial neural networks

[No abstract available]

Zinc and docosahexaenoic acid metabolism in brain cells

This thesis examines the direct interaction of Docosahexaenoic acid (DHA, an omega-3 fatty acid) against zinc-induced mitochondrial dysfunction and involvement of bioenergetic regulation as a zinc toxicity target, which may be the initiator of oxidative stress, caspase cascade, alteration in epigenetic patterns and therefore gene expression in human neuronal cells.

Pretend play of children with acquired brain injury : an exploratory study

Objective: This exploratory study aimed to describe the self-initiated pretend play of three children who had sustained an acquired brain injury (ABI). No previous research was found.

Methods: Three children aged 3.0–6.0 years were recruited through purposive sampling. Pretend play ability was assessed using the Child-Initiated Pretend Play Assessment.

Results: Two of the three children scored below the range expected for children their age and one child scored above the range, indicating a wide range of pretend play ability for the children. None of the children could sustain their engagement in pretend play to complete the time of the assessment.

Conclusion: Complex pretend play ability is a functional assessment of cognitive ability involving sequential planning, problem-solving, language and social understanding. Cognitive fatigue is argued to explain the children's limited ability to engage in play for the time expected for their ages. More research is required.

Compact stacked planar inverted-F antenna for passive deep brain stimulation implants

A compact meandered three-layer stacked circular planar inverted-F antenna is designed and simulated at the UHF band (902.75 – 927.25 MHz) for passive deep brain stimulation implants. The UHF band is used because it offers small antenna size, and high data rate. The top and middle radiating layers are meandered, and low cost substrate and superstrate materials are used to limit the radius and height of the antenna to 5 mm and 1.64 mm, respectively. A dielectric substrate of FR-4 of εr= 4.7 and δ= 0.018, and a biocompatible superstrate of silicone of er= 3.7 and d= 0.003 with thickness of 0.2 mm are used in the design. The resonance frequency of the proposed antenna is 918 MHz with a bandwidth of 24 MHz at return loss of −10 dB in free space. The antenna parameter such as 3D gain pattern of the designed antenna within a skin-tissue model is evaluated by using the finite element method. The compactness, wide bandwidth, round shape, and stable characteristics in skin make this antenna suitable for DBS. The feasibility of the wireless power transmission to the implant in the human head is also examined.

Application of growing self-organizing map to distinguish between finger tapping and non tapping from brain images

Growing self-organizing map (GSOM) has been characterized as a knowledge discovery visualization application which outshines the traditional self-organizing map (SOM) due to its dynamic structure in which nodes can grow based on the input data. GSOM is utilized as a visualization tool in this paper to cluster fMRI finger tapping and non- tapping data, demonstrating the visualization capability to distinguish between tapping or non-tapping. A unique feature of GSOM is a parameter called the spread factor whose functionality is to control the spread of the GSOM map. By setting different levels of spread factor, different granularities of region of interests within tapping or non-tapping images can be visualized and analyzed. Euclidean distance based similarity calculation is used to quantify the visualized difference between tapping and non tapping images. Once the differences are identified, the spread factor is used to generate a more detailed view of those regions to provide a better visualization of the brain regions.