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Epidemiological and laboratory research supports a relationship between acute alcohol intoxication and aggression. Recent data suggest that alcohol disrupts cognitive abilities associated with frontal lobe function. Moreover, neuropsychological research provides suggestive evidence that frontal lobe dysfunction may predispose an individual to increased aggression. The research recounted in this thesis was conducted to investigate the role of individual differences of cognitive abilities associated with the dorsolateral frontal cortex in aggressive behaviour and to test the hypothesis that alcohol indirectly potentiates aggression by impairing these cognitive abilities. The three experiments included in this thesis demonstrated that: (1) acute alcohol intoxication interferes with the ability to integrate previously acquired knowledge in the formulation of behavioral strategies; (2) individuals grouped according to performance on two neuropsychological tests of cognitive abilities associated with frontal lobe function differ in degree of aggressive response. Specifically, individuals in the lower versus upper performance quartiles became more aggressive when provoked; and (3) individuals in the upper cognitive performance quartile demonstrate significantly greater reductions of unprovoked aggression in response to monetary reward.

The ability to generate different responses, and the ability to inhibit inappropriate behaviour, were explored in patients with unilateral cerebral excisions. Site-of-lesion effects were found to interact with the sex of the subject, the time of test-administration, and the nature of the response criteria. In Part I, the Thurstone Word Fluency Test revealed impairments two weeks postoperatively in patients with frontal, temporal, or central-area lesions. In men, removals from the left cerebral hemisphere caused greater deficits than removals from the right, but only left central-area excisions resulted in long-lasting impairments. Patients with left frontal-lobe removals produced few words on a sentence-completion fluency task, but on visual-image fluency, no patient-group was impaired. In Part II, an inability to inhibit impulsive actions on risk-taking tasks was seen after frontal lobectomy, as was a tendency to disregard the instructions on a word-fluency task. These results are consistent with the fact that patients with frontal-lobe lesions described themselves on a behavioural-trait questionnaire as less flexible and more impulsive than did control subjects.

Through a holographic recording a property from the third dimension, the depth, is obtained in the form of a phase map of the incident light. One wavelength holography will have a unique phase for the depth range corresponding to the wavelength of the light and outside this range the real depth can not be resolved. By introducing more wavelengths to the measurement the unique phase combination of the waves will have a wider range and larger objects can be resolved. Up to six wavelengths can be simultaneous recorded by making them occupy different spatial frequencies. A set of spatial frequencies together describing a property of the wave is referred to as a lobe. For more than 6 wavelengths and a larger depth range produced by a more seldom repeated unique phase combination the individual waves will occupy the same frequencies, i.e. the lobes overlap. The separation of overlapping lobes is essential in order to make precise and time independent measurements of large and/or moving objects. To separate the lobes the complex fields, i.e. the phases together with the amplitudes, were simulated to propagate a distance and again recorded. The propagation leads to a phase shift of the spatial frequencies which reveals the complex fields in the case of two overlapping wavelengths. For three overlapping wavelengths the resolution, i.e spatial frequencies describing the object, has to be reduced in order to determine the individual complex fields. Since the propagation is a linear transformation for the frequencies that do not overlap, only the overlapping elements whose propagation is nonlinear produce new information. The new information gained is therefore independent of the number of wavelengths used which limits the exact determination of the fields to two wavelengths. Through the holographic recording another property of the complex field is obtained which is the superimposed individual intensities. This bounds the complex fields to certain values, i.e. restricts the possible amplitude of the waves. The recording in the two planes produces two intensity distributions which both must be satisfied by the complex fields. The optimization model for this was formulated and a simple optimization algorithm was implemented. Instead of an equality constraint of the intensities the inequality constraint was implemented, mainly due to that the optimization process was out of the scope of the thesis and the inequality constraint resulted in a simple implementation. The result pointed out important properties even though the optimization could not separate the fields satisfactorily for more than three wavelengths. The inequality constraint contains enough information to solve the case of three overlapping wavelengths.

Thesis (Ph. D.)--University of California, San Diego, 2008. / Title from first page of PDF file (viewed September 3, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 128-137).

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M.A. / With the advances achieved in medical technology in recent years, society is increasingly faced with the issue of determining how fit individuals are for reintegration in society following the event of traumatic brain injury. Together with Neurology and it's diagnostic capabilities, many other disciplines such as Neuropsychology, Physiotherapy and Occupational Therapy, to name but a few, have placed strong emphasis on the rehabilitation of individuals with brain damage, with a view to reintegrate them into society. Besides the physical rehabilitation which aims at normalizing the individual's physical health, issues such as psychological ,cognitive and social functioning have been the focus of a great body of research in recent years. Whereas in the past the prognosis for many such patients in respect of returning to a normal life style were discouraging, health workers are now more optimistic in most cases regarding the individuals' probability to achieve a higher level of functioning after recovery. In this context, the individuals' ability to function in society, their ability to be integrated into the family and working environment and competence to be active and valued members of society have thus become the new aims which the therapeutic team together with the patient strive to achieve. With this in mind, rehabilitation teams now place greater emphasis and effort on optimizing recovery in the areas of cognitive and emotional competence. Amongst these issues, the individuals' competence to make moral judgements and socially adequate decisions in everyday living is of the utmost importance. This impacts on their ability to abide by social rules and norms which will determine their competence and desirability as active members in the family, social and working environments. This is the main focus of the present study. The issue of moral judgement and behaviour is central to this discussion, and a delineation of what defines morality and moral judgement is mandatory. Contributions to this analysis were found in the writings of the various authors and schools of thought presented here, and each of them has dealt with the theme of morality, moral behaviour and judgement from a different theoretical perspective. Theorists such as Lawrence Kohlberg made a major contribution to the understanding of the development of moral judgement through his stage theory, which forms one of the cornerstones of the present study. The site and the severity of the brain injury is paramount to the prognosis for rehabilitation. The frontal lobes have been described as the structures responsible for the widest range of symptoms and seen as the seat of intellect, responsible for deviations in moral and emotional functioning. An overview of the frontal lobes and associated cognitive functions as well as behaviors observed as a result of injury to these structures is presented. The existential-phenomenological system of inquiry has been described by its proponents as the most adequate to investigate phenomena relating to human behaviour, when an understanding of the subjective experience of the individuals involved is desired. For this reason this methodology is used in the present study to facilitate a qualitative analysis of the experience of brain injury particularly in respect of possible alterations in moral judgement and behaviour following the accident. The present investigation is based on interviews with three subjects and their primary caretakers, who answered questions regarding moral dilemmas. These dilemmas aim at tapping the individual's underlying reasoning processes when faced with the decision of what is right and wrong. The analysis and integration of the data obtained through these interviews reveals a complex cluster of alterations in thought and behaviour, much in line with those expected from patients suffering traumatic injury of the frontal lobes. Although different behaviours were revealed by each participant in this study, they were generally in line with the alterations described in the literature resulting from injury to the described brain areas. The value of this study lies in projecting a clearer picture of the experience of brain injury from the point of view of the victims as well as the close family members. Furthermore, analysis of data obtained in this investigation highlights certain typical behaviors and responses observed in individuals with such brain injuries, as described in the literature presented here.

Ce mémoire est consacré à l’étude et au développement d’un nouveau système antennaire agile en rayonnement appelé MARPEM (Matrice Agile Rayonnante à Pixels Elaborés en Métamatériaux). Ce système est formé d’une matrice planaire formée par un agencement jointif de pixels électromagnétiques. Le concept du pixel est inspiré de l’antenne à Bande Interdite Electromagnétique et entouré par une enceinte murale. Ces pixels sont alimentés par des circuits de formation de faisceaux.Des études théoriques approfondies ont montré des performances électromagnétiques de MARPEM concernant le faible couplage mutuel, les forts pointages électroniques et l’élimination de lobes de réseau. Trois prototypes ont été étudiés et réalisés afin de valider expérimentalement les performances de MARPEM et de répondre aux exigences de différentes applications. / This PhD thesis is dedicated to the study and the development of a novel agile antenna system called ‘Agile Radiating Matrix with Metamaterials Pixels’. This system is formed by a planar matrix which is composed by an association of jointed electromagnetic pixels. The pixel design is inspired from the electromagnetic band gap antenna and it is surrounded by metallic walls. These pixels are fed by means of several beam forming networks.The intensive theoretical study made on the matrix antenna, showed several electromagnetic performances concerning the low mutual coupling, the great beam steering for high scanning angles and the elimination of grating lobes. Three manufactured prototypes are presented in order to experimentally validate the matrix performances and to respond to some application requirements.

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