Post-traumatic stress disorder (PTSD) is a severe anxiety disorder affecting cognitive function. 1 in 4 individuals exposed to a life-threatening event may develop PTSD, which is characterised by symptoms of hyperarousal, avoidance and intrusions. Although treatment is effective in most cases, the response is far from satisfactory. It is now clear that novel drug treatment and a better understanding of the neurobiology of PTSD are necessary if we are to realise a better response and treatment outcome in these patients. Glutamatergic pathways play an important role in cognition, while recent studies have emphasized a causal role for glutamate in PTSD, and of the potential value of glutamate receptor modulators in treating the disorder. Stress-related elevation in glutamate exerts detrimental effects on cognition, especially via activation of the N-methyl-D-aspartate (NMDA) receptor, and has been implicated in PTSD associated cognitive deficits. Recently, the cr-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptor has been found to exert a modulatory action on NMDA receptor function. Ampakines are positive allosteric modulators of the AMPA receptor, and have demonstrated beneficial effects in animal models of learning as well as antidepressant action, and to improve short-term memory in humans. The aims of this study were firstly to study the effects of the ampakine, Org 26576, on spatial memory performance in healthy male Sprague-Dawley rats. Secondly, since PTSD is associated with pronounced deficits in cognition, we studied the ability of Org 26576 to modify stress-evoked spatial memory deficits in rats subjected to single prolonged stress (SPS), a putative animal model of PTSD. In both cases, neuroreceptor studies were performed to determine any relationship between hippocampal and cortical NMDA receptor binding characteristics and effects on spatial memory performance. After exposure of the animals to either normal handling or SPS conditions, spatial memory performance was assessed using a 5 day memory acquisition and consolidation protocol in a modified version of the Morris water maze (MWM). Experimental and control groups both received either saline (1 ml/kg i.p.) or Org 26576 at incremental doses of 1, 3 or 10 mg/kg intraperitoneally twice daily for 12 days. Separate groups of animals were used for the neuroreceptor studies, except that behavioural testing was not performed. 24hrs after drug treatment discontinuation, the animals were sacrificed and frontal cortex and hippocampus removed for NMDA receptor binding analysis. In normal rats, Org 26576 3 mg/kg and 10 mg/kg exerted a short-lasting reduction in escape latency on day 1, but which lost prominence over the subsequent training days. Org 26576 1, 3 and 10 mg/kg, however, significantly improved spatial memory retrieval on day 5. No changes in frontal cortical or hippocampal NMDA receptors were observed. Contrary to expected, rats subjected to SPS failed to express noteworthy deficits in spatial memory as previously described. Treatment of SPS-exposed animals with Org 26576 did not significantly alter spatial learning evident in SPS animals on day 1 of acquisition training, as well as on subsequent training days. Org 26576 1 mg/kg increased spatial memory retrieval compared to the unstressed saline control, but not compared to the SPS group. Org 26576 only at a dose of 1 mg/kg decreased cortical, but not hippocampal NMDA receptor density (Bmax) in SPS animals versus unstressed but not saline treated SPS animals. No changes in receptor affinity (Kd) were noted. Org 26576 therefore improves early initial spatial learning in healthy rats, but exerts a lesser effect on memory consolidation over the remainder of the training period. However, Org 26576 significantly improves retrieval of spatial memory without simultaneous changes in frontal cortical and hippocampal NMDA receptor binding. Org 26576 thus may benefit both short-term and long-term memory processes in normal animals without effects on limbic NMDA receptor binding, and provides a rationale for testing in conditions that present with cognitive disturbances. However, the SPS model failed to engender marked deficits in spatial memory performance; this result ultimately complicated the interpretation of the combined stress-drug treatment studies. Studies in healthy animals therefore conclude that Org 26576 is an effective agent to enhance long-term memory processes and should be investigated further for its possible application in disorders of cognition. Although the value of Org 26576 in an animal model of PTSD were inconclusive, further studies in SPS and other PTSD models, as well as models of relevance for schizophrenia, Alzheimer's disease and depression, are encouraged. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2009.

The human central auditory system can automatically extract abstract regularities from a variant auditory input. To this end, temporarily separated events need to be related. This study tested whether the timing between events, falling either within or outside the temporal window of integration (~350 ms), impacts the extraction of abstract feature relations. We utilized tone pairs for which tones within but not across pairs revealed a constant pitch relation (e.g., pitch of second tone of a pair higher than pitch of first tone, while absolute pitch values varied across pairs). We measured the mismatch negativity (MMN; the brain’s error signal to auditory regularity violations) to second tones that rarely violated the pitch relation (e.g., pitch of second tone lower). A Short condition in which tone duration (90 ms) and stimulus onset asynchrony between the tones of a pair were short (110 ms) was compared to two conditions, where this onset asynchrony was long (510 ms). In the Long Gap condition, the tone durations were identical to Short (90 ms), but the silent interval was prolonged by 400 ms. In Long Tone, the duration of the first tone was prolonged by 400 ms, while the silent interval was comparable to Short (20 ms). Results show a frontocentral MMN of comparable amplitude in all conditions. Thus, abstract pitch relations can be extracted even when the within-pair timing exceeds the integration period. Source analyses indicate MMN generators in the supratemporal cortex. Interestingly, they were located more anterior in Long Gap than in Short and Long Tone. Moreover, frontal generator activity was found for Long Gap and Long Tone. Thus, the way in which the system automatically registers irregular abstract pitch relations depends on the timing of the events to be linked. Pending that the current MMN data mirror established abstract rule representations coding the regular pitch relation, neural processes building these templates vary with timing.

The investigation of the atmospheric fate and transport of semi-volatile organic compounds (SOCs) often requires the sampling of large volumes of air (>100 m3) in a relatively short period of time. Conventionally high-volume pumps are not suitable for remote areas without access to reliable network power. We have developed a flow through sampler for such situations. It consists of a horizontally-oriented flow-tube, that can collect gaseous and particle-bound SOCs from large volumes of air by turning into the wind and having the wind blow through a porous sampling medium such as polyurethane foam. Through both indoor and outdoor experiments, we quantified its air sampling rate (through battery operated anemometers inside and outside of the flow tube), its sampling efficiency (by theoretical plate number analysis of the break-though curves for PCBs, PAHs, OCPs and PBDEs), and its accuracy (by comparison of concentrations, time trends, temperature dependences and isomer ratios with those obtained by conventional high-volume sampling) under conditions of constant and variable meteorological conditions (wind speed, temperature). The flow-through sampler was deployed to monitor SOC concentrations at a remote Chinese research station located close to Nam Co Lake, Tibet. During the campaign, fifteen 1 month-long samples were taken, corresponding to sample volumes between 5,000 and 20,000 m3. Despite those large sample volumes, only HCB and HCHs experienced break-through, but application of frontal chromatograph theory allows the estimation of breakthrough-corrected air concentrations even for those relatively volatile SOCs. The pesticide levels at Nam Co are generally very low. Most pesticides had higher levels during summer, resulting in a strong temperature dependence. This is correlated with air mass origin across the Himalayas in the Gangetic plains of India and Bangladesh. The flow through sampler constitutes a feasible method for reliably and quantitatively collecting SOCs from large air volumes.

Frontal Protection Systems (FPS) have become a popular accessory for passenger vehicles. They are used to protect the front of a vehicle during minor impacts, and to attenuate the impact energy during major impacts. With the increased safety of modern passenger vehicles, the fitment of a FPS to a vehicle requires careful consideration to the design and installation of the FPS as they may modify vehicle crush characteristics. This is particularly important in vehicles fitted with air bags. These community and industry concerns triggered the research discussed in this thesis, which is the first comprehensive project undertaken in this particular area. This project generated comprehensive research knowledge on the impact response and energy absorption of FPS in order to evaluate performance. This involved a range of experimental testing supplemented by finite element analysis. Experimental testing was conducted using quasi-static and dynamic techniques to assess the overall performance of current FPS available. Finite element models were then generated and analysed using both implicit and explicit techniques, and calibrated against the experimental testing results. These models were used throughout the project to assess the FPS response, in particular the energy absorbed, to changes in impact characteristics. FPS assessment guidelines were developed from the knowledge generated from the numerous FPS tests and analyses carried out in this research project. These guidelines have been used in the design and evaluation of a number of FPS for airbag compatibility. The real life performance of vehicles fitted with these FPS, have given confidence to the assessment criteria developed in this research project. This project has demonstrated that FPS can be designed to complement the safety systems of modern passenger vehicles, and thus passenger safety. This would not have been possible without the comprehensive research carried out in this project.

The requirement to operate vehicles in low light and/or night environments whilst wearing night vision goggle (NVG) systems has become increasingly common during military operations. There is very limited research investigating injury risks associated with these systems during ground vehicle collisions. This study examined the injury risks associated with wearing the Australian Defence Force - Enhanced Combat Helmet (ECH) and NVG system, in frontal vehicle collisions. This project consisted of two components: (1) crash tests using a sled and (2) numerical simulations of impacts. Four dynamic sled tests were conducted using a 50th percentile, male, Hybrid III dummy positioned on a rigid seat. Frontal impact tests were performed at a 40 km/h change in velocity (*v) and 20 g deceleration. The test configurations were as follows: (a) Base; (no helmet or additional equipment); (b) ECH; and, (c) ECH and NVG. Condition (c) was carried out twice, to determine repeatability. The sled test protocols were reconstructed precisely with the numerical simulation package MADYMO and the simulations were shown to correlate well with the experimental results. Using this validated model, four parametric studies were undertaken to assess the influence of counterweights, seat cushion, seatbelt pre-tensioner, and the vehicle's *v and acceleration on injury risks. The study found that neck loads were within acceptable limits, with the exception of the neck extension moment, which was exceeded for all NVG conditions. Based on the parametric studies, no major improvements were observed in the neck extension moments with the use of counterweights or a seat cushion. In contrast the use of a seatbelt pre-tensioner was observed to decrease greatly this neck injury risk in certain scenarios. The study also identified that a *v of 15 km/h and peak acceleration of up to 14 g were required to keep the neck extension moment below the prescribed injury criteria. However, the high neck extension moment values may have been partially attributable to the stiff Hybrid III neck. This study identified a possible injury mechanism for soldiers using the ECH and NVG system during specific impact scenarios. The method applied in this project was designed to be repeatable.

Background: Patients with non-penetrating traumatic brain injuries (TBI) are at high risk for damage to ventral prefrontal brain regions, due to the brain’s acceleration into the bony ridges of the anterior portions of the skull. Current neuropsychological assessments of these patients focus mainly on the assessment of so-called “executive functions,” which are associated with dorsolateral prefrontal regions. Ventral prefrontal pathology is more likely to disrupt social and emotional functions, but assessments of these abilities using objective measurements that require patients to demonstrate their competence are rare. Mounting evidence suggests that chronic social and emotional deficits are common in TBI, and that these difficulties result in significant functional impairments post-injury, making clear the need to develop and use objective assessment tools during clinical neuropsychological assessments. Methods: In the current project, the Global Interpersonal Skills Test (GIST), a questionnaire measure of social skills with both a self-rated and an informant-rated version, was developed, along with three novel or adapted performance-based measures of social and emotional functioning. The first novel measure was the Assessments of Social Context (ASC), a video-based task examining comprehension of social context using non-verbal cues, including the identification of emotions, intensions and positive or negative attitudes of one person towards another. The second task was the Awareness of Interoception Test (AIT), a heartbeat detection paradigm adapted from previous literature that measures participants’ sensitivity to their cardiac function, which is implicated in basic emotional functioning. The third task was the Social Interpretations Task (SIT), an animation-based task adapted from previous literature examining participants’ ability to apply a social interpretation to stimuli that are not inherently social in nature. All novel tasks were developed and piloted with healthy undergraduates. A group of patients with moderate to severe TBI (N = 16), and a group of non-brain damaged controls (N = 16) underwent neuropsychological testing. Standard neuropsychological measures including the Wechsler Test of Adult Reading, Digit Span and Digit Symbol Coding from the Wechsler Adult Intelligence Scale, phonemic (FAS) and semantic fluency (Animals) from the Verbal Fluency Test, and the Trail Making Test, as well as the novel measures to both patients with TBI and controls were administered. The following predictions were made: vi 1) The novel performance-based measures of social abilities would be more sensitive to the presence of moderate and severe TBI than the standard neuropsychological measures of cognition; 2) On the informant version of the GIST, but not the self-report version, patients would have scores than controls; 3) Patients’ performance on the ASC would be less accurate than controls’, and this difference would be associated with real-world social skills, measured by the informant-version of the GIST; 4) Patients’ AIT performance would be less accurate than controls’, and this would be related to their self-rated emotional changes; 5) Patients’ SIT performance would be less accurate than controls’, and this difference would be associated with real-world social skills, again measured by the informant-version of the GIST. Findings: Findings were consistent with these hypotheses: 1) A statistically significant logistic regression revealed that a Social composite variable comprising the ASC, AIT and SIT was more sensitive to the presence of TBI (β = 9.59, p < .05) than a Cognitive composite variable comprising Digit Symbol Coding, Trails B completion time, and Phonemic Fluency (β = 0.006, p = .466). 2) A multivariate analysis of variance (MANOVA) revealed that informants of patients gave lower GIST scores to patients than the informants of controls (F(1,28) = 22.2, p < 0.0001), whereas there were no differences between groups on the self-rated version of the GIST (F(1,28) = .35, p = .56); 3) Patients’ ASC performance was significantly poorer than controls’ on a MANOVA (F(1,31) = 21.7, p < .0001), and ASC total scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .624, p < .0001). 4) Patients’ AIT performance was significantly poorer than controls’ using an independent samples t test (t(13) = 1.43, p < 0.005), and qualitative investigation of subjective reports of emotional change among patients suggested a potential relationship between emotional changes and AIT performance. vii 5) Patients’ SIT performance was significantly poorer than controls on an independent samples t test (t(30) = -2.12, p < 0.05), and SIT scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .460, p < .0001). Interpretation: This research represents a preliminary step in the development of clinically useful measures of social and emotional difficulties following TBI. Given the small sample size of the patient group, and the presence of co-morbid difficulties among some of the participants in this research, further testing of these measures in larger, more homogeneous samples would strengthen the current results, as would using a comparison group of people with milder TBI, rather than neuro-typical controls. The complexity of social behaviour requires that the current measures be further validated against other real-world assessments of social ability, and that assessments of other aspects of social behaviour be conducted. Nonetheless, the measures described here are a promising start to supplementing the neuropsychological toolkit in an area that requires further development at the present time.

Background: Patients with non-penetrating traumatic brain injuries (TBI) are at high risk for damage to ventral prefrontal brain regions, due to the brain’s acceleration into the bony ridges of the anterior portions of the skull. Current neuropsychological assessments of these patients focus mainly on the assessment of so-called “executive functions,” which are associated with dorsolateral prefrontal regions. Ventral prefrontal pathology is more likely to disrupt social and emotional functions, but assessments of these abilities using objective measurements that require patients to demonstrate their competence are rare. Mounting evidence suggests that chronic social and emotional deficits are common in TBI, and that these difficulties result in significant functional impairments post-injury, making clear the need to develop and use objective assessment tools during clinical neuropsychological assessments. Methods: In the current project, the Global Interpersonal Skills Test (GIST), a questionnaire measure of social skills with both a self-rated and an informant-rated version, was developed, along with three novel or adapted performance-based measures of social and emotional functioning. The first novel measure was the Assessments of Social Context (ASC), a video-based task examining comprehension of social context using non-verbal cues, including the identification of emotions, intensions and positive or negative attitudes of one person towards another. The second task was the Awareness of Interoception Test (AIT), a heartbeat detection paradigm adapted from previous literature that measures participants’ sensitivity to their cardiac function, which is implicated in basic emotional functioning. The third task was the Social Interpretations Task (SIT), an animation-based task adapted from previous literature examining participants’ ability to apply a social interpretation to stimuli that are not inherently social in nature. All novel tasks were developed and piloted with healthy undergraduates. A group of patients with moderate to severe TBI (N = 16), and a group of non-brain damaged controls (N = 16) underwent neuropsychological testing. Standard neuropsychological measures including the Wechsler Test of Adult Reading, Digit Span and Digit Symbol Coding from the Wechsler Adult Intelligence Scale, phonemic (FAS) and semantic fluency (Animals) from the Verbal Fluency Test, and the Trail Making Test, as well as the novel measures to both patients with TBI and controls were administered. The following predictions were made: vi 1) The novel performance-based measures of social abilities would be more sensitive to the presence of moderate and severe TBI than the standard neuropsychological measures of cognition; 2) On the informant version of the GIST, but not the self-report version, patients would have scores than controls; 3) Patients’ performance on the ASC would be less accurate than controls’, and this difference would be associated with real-world social skills, measured by the informant-version of the GIST; 4) Patients’ AIT performance would be less accurate than controls’, and this would be related to their self-rated emotional changes; 5) Patients’ SIT performance would be less accurate than controls’, and this difference would be associated with real-world social skills, again measured by the informant-version of the GIST. Findings: Findings were consistent with these hypotheses: 1) A statistically significant logistic regression revealed that a Social composite variable comprising the ASC, AIT and SIT was more sensitive to the presence of TBI (β = 9.59, p < .05) than a Cognitive composite variable comprising Digit Symbol Coding, Trails B completion time, and Phonemic Fluency (β = 0.006, p = .466). 2) A multivariate analysis of variance (MANOVA) revealed that informants of patients gave lower GIST scores to patients than the informants of controls (F(1,28) = 22.2, p < 0.0001), whereas there were no differences between groups on the self-rated version of the GIST (F(1,28) = .35, p = .56); 3) Patients’ ASC performance was significantly poorer than controls’ on a MANOVA (F(1,31) = 21.7, p < .0001), and ASC total scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .624, p < .0001). 4) Patients’ AIT performance was significantly poorer than controls’ using an independent samples t test (t(13) = 1.43, p < 0.005), and qualitative investigation of subjective reports of emotional change among patients suggested a potential relationship between emotional changes and AIT performance. vii 5) Patients’ SIT performance was significantly poorer than controls on an independent samples t test (t(30) = -2.12, p < 0.05), and SIT scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .460, p < .0001). Interpretation: This research represents a preliminary step in the development of clinically useful measures of social and emotional difficulties following TBI. Given the small sample size of the patient group, and the presence of co-morbid difficulties among some of the participants in this research, further testing of these measures in larger, more homogeneous samples would strengthen the current results, as would using a comparison group of people with milder TBI, rather than neuro-typical controls. The complexity of social behaviour requires that the current measures be further validated against other real-world assessments of social ability, and that assessments of other aspects of social behaviour be conducted. Nonetheless, the measures described here are a promising start to supplementing the neuropsychological toolkit in an area that requires further development at the present time.

Background: Patients with non-penetrating traumatic brain injuries (TBI) are at high risk for damage to ventral prefrontal brain regions, due to the brain’s acceleration into the bony ridges of the anterior portions of the skull. Current neuropsychological assessments of these patients focus mainly on the assessment of so-called “executive functions,” which are associated with dorsolateral prefrontal regions. Ventral prefrontal pathology is more likely to disrupt social and emotional functions, but assessments of these abilities using objective measurements that require patients to demonstrate their competence are rare. Mounting evidence suggests that chronic social and emotional deficits are common in TBI, and that these difficulties result in significant functional impairments post-injury, making clear the need to develop and use objective assessment tools during clinical neuropsychological assessments. Methods: In the current project, the Global Interpersonal Skills Test (GIST), a questionnaire measure of social skills with both a self-rated and an informant-rated version, was developed, along with three novel or adapted performance-based measures of social and emotional functioning. The first novel measure was the Assessments of Social Context (ASC), a video-based task examining comprehension of social context using non-verbal cues, including the identification of emotions, intensions and positive or negative attitudes of one person towards another. The second task was the Awareness of Interoception Test (AIT), a heartbeat detection paradigm adapted from previous literature that measures participants’ sensitivity to their cardiac function, which is implicated in basic emotional functioning. The third task was the Social Interpretations Task (SIT), an animation-based task adapted from previous literature examining participants’ ability to apply a social interpretation to stimuli that are not inherently social in nature. All novel tasks were developed and piloted with healthy undergraduates. A group of patients with moderate to severe TBI (N = 16), and a group of non-brain damaged controls (N = 16) underwent neuropsychological testing. Standard neuropsychological measures including the Wechsler Test of Adult Reading, Digit Span and Digit Symbol Coding from the Wechsler Adult Intelligence Scale, phonemic (FAS) and semantic fluency (Animals) from the Verbal Fluency Test, and the Trail Making Test, as well as the novel measures to both patients with TBI and controls were administered. The following predictions were made: vi 1) The novel performance-based measures of social abilities would be more sensitive to the presence of moderate and severe TBI than the standard neuropsychological measures of cognition; 2) On the informant version of the GIST, but not the self-report version, patients would have scores than controls; 3) Patients’ performance on the ASC would be less accurate than controls’, and this difference would be associated with real-world social skills, measured by the informant-version of the GIST; 4) Patients’ AIT performance would be less accurate than controls’, and this would be related to their self-rated emotional changes; 5) Patients’ SIT performance would be less accurate than controls’, and this difference would be associated with real-world social skills, again measured by the informant-version of the GIST. Findings: Findings were consistent with these hypotheses: 1) A statistically significant logistic regression revealed that a Social composite variable comprising the ASC, AIT and SIT was more sensitive to the presence of TBI (β = 9.59, p < .05) than a Cognitive composite variable comprising Digit Symbol Coding, Trails B completion time, and Phonemic Fluency (β = 0.006, p = .466). 2) A multivariate analysis of variance (MANOVA) revealed that informants of patients gave lower GIST scores to patients than the informants of controls (F(1,28) = 22.2, p < 0.0001), whereas there were no differences between groups on the self-rated version of the GIST (F(1,28) = .35, p = .56); 3) Patients’ ASC performance was significantly poorer than controls’ on a MANOVA (F(1,31) = 21.7, p < .0001), and ASC total scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .624, p < .0001). 4) Patients’ AIT performance was significantly poorer than controls’ using an independent samples t test (t(13) = 1.43, p < 0.005), and qualitative investigation of subjective reports of emotional change among patients suggested a potential relationship between emotional changes and AIT performance. vii 5) Patients’ SIT performance was significantly poorer than controls on an independent samples t test (t(30) = -2.12, p < 0.05), and SIT scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .460, p < .0001). Interpretation: This research represents a preliminary step in the development of clinically useful measures of social and emotional difficulties following TBI. Given the small sample size of the patient group, and the presence of co-morbid difficulties among some of the participants in this research, further testing of these measures in larger, more homogeneous samples would strengthen the current results, as would using a comparison group of people with milder TBI, rather than neuro-typical controls. The complexity of social behaviour requires that the current measures be further validated against other real-world assessments of social ability, and that assessments of other aspects of social behaviour be conducted. Nonetheless, the measures described here are a promising start to supplementing the neuropsychological toolkit in an area that requires further development at the present time.

Made available in DSpace on 2013-08-07T19:04:54Z (GMT). No. of bitstreams: 1 000423293-Texto+Completo-0.pdf: 2837320 bytes, checksum: 31cc78d53c5f9be61576ff633d9d8022 (MD5) Previous issue date: 2010 / Introduction: The police officer are among the professionals that hold larger exposition into danger situation and aggression. Abilities like initiative, planning, actions’ programming, flexibility, selective attention, concentration, operative memory and impulsive control, when used efficiently, pass to be determinant into the success of the police officer’s work. Knowing the stress’ impact into the operation of these abilities, will provide possibilites to increase the technician’s preparation of these professionals. Objectives: Evaluate the executive functions on civil police officers and identify the stress presence or not in these police officers. Material and Methods: There were evaluated 40 citizens, divided in two groups: 20 Civil police officers into the operational área and 20 police officers into the administrative area. The methodology focus was the quatitative research, with the following tests: Frontal Evaluation Battery (FEB): instrument that evaluates the dependent funcions from the lobe, compound from six subtests, Register to the stress symptoms for adults –Lipp(ISSL) developed to measure the level of global stress. Concentrated Attention – (CA ) Evaluates the capacity in keeping attention in working, in during some period. Results: The police officers in the operational area presented a significantly performance into executive functions (p= 0,031), when compared with the police officers in the administrative area. Throught the Stress Inventary Symptoms - Lipp (ISSL) it was verified that 10,0% (n=2) of the operational group of the pertain citizens got positive stress diagnosis, while, in the administrative group this number was 45,0% (n=9). The administrative group presented higher probability to positive stress diagnosis, with phychic prevalence sumptoms. The police officers that belonged to the administrative area, presented higher stress index than the operational group and worse executive functioning into the FEB test. On the AC test the average of the hits of the administrative group was (93,5 ± 24,5), presenting better performance when compared with the average of the hits from the operatinal group (82,68 ± 24,89), however this result is not statistically significant, due the p= 0,182. Conclusion: The positive stress diagnosis correlated with the worst executive functioning into the administrative group. The operational group showed less stress level, associated with the best performance of the executive functions than the administrative group. The performance into the Concentrated Attention’s test did not show significant difference between the groups. / Introdução: Os policiais estão entre os profissionais que possuem maior exposição a situação de perigo e agressão. Habilidades como iniciativa, planejamento, programação de ações, flexibilidade, atenção seletiva, concentração, memória operativa e controle de impulsos, quando utilizadas com eficiência, passam a ser determinantes para o sucesso do trabalho policial. Conhecer o impacto do estresse cotidiano no funcionamento destas habilidades auxiliará na atualização de informações e maior preparo técnico destes profissionais. Objetivos: Investigar o impacto do estresse no funcionamento executivo de policiais civis. Sujeitos e Métodos: Foram avaliados 40 sujeitos, divididos em dois grupos: 20 policiais da área operacional e 20 policiais da área administrativa. O enfoque metodológico foi a pesquisa quantitativa, com os seguintes testes: Bateria de Avaliação Frontal (FAB): instrumento que avalia funções dependentes do lobo frontal, composto por seis subtestes. Inventário para sintomas de estresse para adultos–Lipp (ISSL) desenvolvido para medir o nível de estresse global e Atenção Concentrada (AC), para avaliar a capacidade de manter a atenção concentrada no trabalho, durante um período. Resultados: Os policiais da área operacional apresentaram desempenho significativamente melhor nas funções executivas (p=0,031), quando comparados com policiais da área administrativa. Através do Inventário de Sintomas de estresse-Lipp (ISSL) constatou-se que 10,0% (n=2) dos indivíduos pertencentes ao grupo operacional possuem diagnóstico de estresse positivo, enquanto que, no grupo administrativo este número foi de 45,0% (n=9). O grupo administrativo apresentou maior probabilidade de diagnóstico de estresse positivo, com prevalência de sintomas psíquicos. Os policiais que pertencem á área administrativa, apresentaram índice de estresse maior que o grupo operacional e pior funcionamento executivo no teste FAB. No teste AC a média de acertos do grupo administrativo foi de 93,5 ± 24,5, apresentando melhor desempenho quando comparada com a média de acertos do grupo operacional (82,68 ± 24,89), porém resultado não significativo estatisticamente, devido ao p=0,182. Conclusão: O diagnóstico de estresse positivo correlacionou-se com pior funcionamento executivo, no grupo administrativo. O grupo operacional mostrou menor nível de estresse, associado com melhor desempenho de funções executivas do que o grupo administrativo. O desempenho no teste de Atenção Concentrada não mostrou diferença significativa entre os grupos.

The immune system has been suggested as crucial in brain and psychological functioning. More precisely, immune markers reflecting immune system activity are important for psychological and mental health, as evident by their role in the physiopathology of depression and in the impairment of executive functions. Frontal alpha asymmetry (FAA), an electroencephalographic marker of brain function, has also been linked to such psychopathology and is thought to reflect psychological processes underlying approach- versus withdrawal-related motivation and higher-order inhibitory control. Only a few studies have linked FAA to immune markers but notably found a negative association between IL-6, a pleiotropic pro-inflammatory cytokine, and FAA. The aim of the present work is thus to study the relationship between various immune markers (including pro-inflammatory cytokines and IL-6) and FAA. 35 healthy young male participants underwent a resting EEG recording and blood sampling from which immune markers were measured. The results did not suggest an association between IL-6 and FAA. No other immune markers were either suggested to be associated to FAA. The complexity of the immune system (e.g., effect of cytokines) is underlined and may explain the results. Despite such results, the implication of true negative correlations between FAA and circulating immune markers, as suggested in previous studies, is discussed in the light of the theoretical models of FAA.