The introduction of high density EEG (hd-EEG) nets for easy application on subjects of all ages has improved the possibilities to investigate the development of the infant neurophysiology. This dissertation consists of three studies (I – III) that investigate the visual motion system and mirror neuron system of the infant, and methodological sections that outline the bioelectrical background and the characteristics of the methods used. Study I covers the maturation of cortical areas involved in motion perception in adults and infants using an ERP paradigm. Over three age groups (2, 3 and 5 month olds) the cortical activation increased dramatically. All infant groups showed significant activation when moving displays was contrasted to static displays on a video screen. The study shows that 5-month-old infants and older can be expected to process motion in a similar fashion as adults. Study II covers the infant mirror neuron system (MNS). In adults the mu rhythm perturbations is considered a reliable measure of activation of the MNS. This study presented both a mu rhythm analysis and a ERP analysis to detect MNS activity in 6-month-olds and in adults. This study concludes that the infant MNS can be measured using ERPs and that the development of mu rhythm perturbations requires further study. Study III focused on exploring the mu rhythm suppressions. 8-month-olds observed a live actor that performed goal directed reaches and non-goal directed hand movements. The results show robust mu rhythm perturbations time-locked to the grasping moment. The study concluded that the MNS activity is possible to evaluate by analysis of mu rhythm perturbations and that the MNS show mature characteristics at the age of 8 months. In summary, Study 2 and 3 present new methods to investigate the infant mirror neuron system and shows that the infant MNS is active at 6 months of age. At 8 months of age the infant MNS show mature EEG responses to simple actions such as reaching. How the MNS development relates to the infants’ motor development, and how the MNS interacts with the development of social skills requires further studies that could benefit from the methods presented here.

The concept of Sustainable Development is an interdisciplinary science. Transcending various academic fields the concept shows paths how the needs of present and future generations can be met through economic development on a finite natural resource base. Global warming and rising sea levels are just two of a series of phenomena that are directly attributable to human-induced increasing greenhouse gas levels in the atmosphere as consequence of the combustion of fossil fuels. Therefore, reducing greenhouse gas emissions through the use of renewable resources such as bioenergy are of vital importance if detrimental environmental effects are to be mitigated. The production of biogas in a decentralized context is receiving much attention in Germany as a means to reduce greenhouse gases and to counteract correlated negative environmental effects, respectively. In addition, socio-economic benefits such as local employment creation have the potential to empower rural communities. Subsidised by the German Renewable Sources Act and its various remuneration schemes, two 500kWel CHP biogas plants are producing through anaerobic digestion of maize silage and manure electricity and heat in the East German village Bollewick, which is the case study. The sustainability of this decentralized system is analyzed by applying a set of indicators. Socio-economic benefits for the population, economic efficiency of the digestion process and impacts of substrate costs on the profitability, greenhouse gas emissions due to land use change and biodiversity loss being some of these indicators. The thesis concludes that none of the sustainability indicators are sufficiently fulfilled in Bollewick. Especially the cultivation of the energy crop maize has despite crop rotations immense negative environmental effects. Therefore, the decentralized biogas production in the rurally coined village Bollewick is not sustainable.

Grasping is fundamentally important for our successful interaction with the environment. Grasping with both hands is phylogenetically older than the hand yet its underlying mechanisms are poorly understood. The objective of this research is to examine bimanual grasping and its underlying mechanisms. Two experiments were conducted to examine whether bimanual grasping involves both hemispheres equally or only one dominant hemisphere, and to examine whether information crosses at an early visual level and/or at later sensorimotor/motor levels. The first experiment examined participants’ grasping and reaching movements while they fixated either to the left or right of the object. For the second experiment, EEG data was recorded while participants performed a similar task. The results from both experiments suggested that when we grasp an object with both hands, the left and right hemispheres control the action equally, and visual information is shared before it reaches areas that are involved in motor control.

Background: The neurological examination in critically ill patients is limited due to decreased level of consciousness and sedating medications. Electroencephalography (EEG) can be used to monitor brain injury; however, availability is limited. Methods: To determine the perceived need for EEG monitoring in the ICU and its current availability, we used rigorous methodology to develop and disseminate a survey to 199 Canadian critical care physicians. Results: Of 103 (52%) respondents (77% academic practice; 83% adult focus), 75% stated EEG monitoring should be a standard of care; yet, 75.5% were unable to obtain an EEG in an optimal timeframe. Technology under-use was exacerbated during non-standard working hours and greater in adult institutions. Perceived barriers to optimal care were lack of EEG technicians, physicians to interpret EEG and finances. Conclusion: Sub-optimal availability of EEG represents an important gap in the care of neurologically injured patients. Specific barriers represent targets for quality improvement.

Background: The neurological examination in critically ill patients is limited due to decreased level of consciousness and sedating medications. Electroencephalography (EEG) can be used to monitor brain injury; however, availability is limited. Methods: To determine the perceived need for EEG monitoring in the ICU and its current availability, we used rigorous methodology to develop and disseminate a survey to 199 Canadian critical care physicians. Results: Of 103 (52%) respondents (77% academic practice; 83% adult focus), 75% stated EEG monitoring should be a standard of care; yet, 75.5% were unable to obtain an EEG in an optimal timeframe. Technology under-use was exacerbated during non-standard working hours and greater in adult institutions. Perceived barriers to optimal care were lack of EEG technicians, physicians to interpret EEG and finances. Conclusion: Sub-optimal availability of EEG represents an important gap in the care of neurologically injured patients. Specific barriers represent targets for quality improvement.

Severe motor impairments can severely restrict interaction with one's surroundings. Brain computer interfaces combined with text-based communication systems, such as the P300 Speller, have allowed individuals with motor disabilities to spell messages with their EEG signals. Although providing full composition flexibility, they enable communication rates of only a few characters per minute. Utterance-based communication systems have been developed for individuals with disability and have greatly increased communication speeds, but have yet to be applied to BCIs. This paper proposes an utterance-based communication system using the P300-BCI in which words are organized in a network structure that facilitates rapid retrieval. In trials with able-bodied participants, the proposed system achieved greater message speeds, but rated lower in effectiveness than the P300 Speller. Nonetheless, subject preferences and reports of self-perceived effectiveness suggested an inclination towards the proposed word system and thus further investigation of word-based networks is warranted in brain-controlled AAC systems.

Grasping is fundamentally important for our successful interaction with the environment. Grasping with both hands is phylogenetically older than the hand yet its underlying mechanisms are poorly understood. The objective of this research is to examine bimanual grasping and its underlying mechanisms. Two experiments were conducted to examine whether bimanual grasping involves both hemispheres equally or only one dominant hemisphere, and to examine whether information crosses at an early visual level and/or at later sensorimotor/motor levels. The first experiment examined participants’ grasping and reaching movements while they fixated either to the left or right of the object. For the second experiment, EEG data was recorded while participants performed a similar task. The results from both experiments suggested that when we grasp an object with both hands, the left and right hemispheres control the action equally, and visual information is shared before it reaches areas that are involved in motor control.

Background: The neurological examination in critically ill patients is limited due to decreased level of consciousness and sedating medications. Electroencephalography (EEG) can be used to monitor brain injury; however, availability is limited. Methods: To determine the perceived need for EEG monitoring in the ICU and its current availability, we used rigorous methodology to develop and disseminate a survey to 199 Canadian critical care physicians. Results: Of 103 (52%) respondents (77% academic practice; 83% adult focus), 75% stated EEG monitoring should be a standard of care; yet, 75.5% were unable to obtain an EEG in an optimal timeframe. Technology under-use was exacerbated during non-standard working hours and greater in adult institutions. Perceived barriers to optimal care were lack of EEG technicians, physicians to interpret EEG and finances. Conclusion: Sub-optimal availability of EEG represents an important gap in the care of neurologically injured patients. Specific barriers represent targets for quality improvement.

Background: The neurological examination in critically ill patients is limited due to decreased level of consciousness and sedating medications. Electroencephalography (EEG) can be used to monitor brain injury; however, availability is limited. Methods: To determine the perceived need for EEG monitoring in the ICU and its current availability, we used rigorous methodology to develop and disseminate a survey to 199 Canadian critical care physicians. Results: Of 103 (52%) respondents (77% academic practice; 83% adult focus), 75% stated EEG monitoring should be a standard of care; yet, 75.5% were unable to obtain an EEG in an optimal timeframe. Technology under-use was exacerbated during non-standard working hours and greater in adult institutions. Perceived barriers to optimal care were lack of EEG technicians, physicians to interpret EEG and finances. Conclusion: Sub-optimal availability of EEG represents an important gap in the care of neurologically injured patients. Specific barriers represent targets for quality improvement.

Rutinariamente se utilizan los signos clínicos para evaluar el grado de profundidad anestésica. La concentración alveolar mínima (CAM) del anestésico halogenado puede ser una medida objetiva de la potencia y del nivel anestésico. Con la introducción de los relajantes musculares, la CAM puede no ser adecuada para evaluar el grado de profundidad anestésica. Se han utilizado diversos monitores para esta medida, siendo los de la electroencefalografía (EEG) los más utilizados.Objetivos: Establecer el patrón electroencefalográfico del desflurano y los cambios hemodinámicos relacionados con el nivel anestésico. Observar los parámetros electroencefalográficos, como medida de la profundidad anestésica en las tres fases del acto anestésico (inducción, mantenimiento, recuperación). Establecer los cambios en la concentración del anestésico halogenado, administrado para alcanzar un valor del índice biespectral (BIS) entre 40-50, utilizando dos técnicas peridurales diferentes y objetivar si la adición de morfina disminuía el consumo del anestésico. Material y métodos: La primera parte del estudio se realizó sobre 24 pacientes de cirugía ginecológica a las que se monitorizó el EEG y administró desflurano a 0,5, 1 y 1,5 CAM Las variables hemodinámicas y los parámetros electroencefalográficos límite espectral 90 (LE90) y ratio delta fueron recogidos. La segunda parte del estudio se realizo de forma prospectiva sobre 50 pacientes de cirugía abdominal. Las variables hemodinámicas y los parámetros electroencefalográficos se recogieron: basal, antes y después de la intubación orotraqueal, después de la incisión quirúrgica, a los 60' del procedimiento, a los 90', cuando se retiraba el anestésico y el valor del BIS alcanzaba 60, cuando aparecía movimiento y en la extubación orotraqueal. La tercera parte del estudio se aplicó sobre 40 pacientes de cirugía colorrectal. A todos ellos se les colocaba un catéter peridural torácico. Los pacientes eran distribuidos de forma aleatoria y a doble ciego en dos grupos para recibir morfina 0,1% (2ml) a la solución de bupivacaina 0,25% Se administró el sevoflurano con el objetivo de alcanzar un BIS entre 40-50. Después de la extubación se preguntaba a los pacientes sobre la presencia de dolor.Resultados: La tensión arterial disminuyó al alcanzar una CAM de 1,5 y aumentó al retirar el anestésico halogenado, la frecuencia cardiaca no varió. Un descenso significativo del LE90 apareció al alcanzar una CAM de 1,5, indicando un plano anestésico más profundo. Aumentó durante la intubación, después de la intubación orotraqueal, a CAM de 0,5 y durante la extubación, indicando un nivel anestésico superficial. El valor del BIS disminuyó desde 95,6 hasta 34,7 y el LE90 desde 20,5 hasta 11,9 después de la inducción anestésica. Durante la recuperación anestésica el valor medio del BIS pasó desde 59,2 hasta 92,3 y el LE90 desde 15,1 hasta 22.2 Hz; la frecuencia cardiaca aumentó mientras que la presión arterial no. Los valores del EEG cuando apareció movimiento fueron de 77 para el BIS, (rango 58-96) y del LE90 de 18Hz (13-18). No hubieron diferencias significativas respecto a las concentraciones espiradas de sevoflurano para valores idénticos de BIS. El grupo bupivacaina-morfina presentó una menor valoración del dolor, en el momento de la extubación (no dolor al movimiento, 79% vs 31,5% p<0,01).Conclusiones: Podemos concluir que el EEG procesado ofrece una buena medida de la profundidad anestésica, ya que refleja los cambios de forma significativa en cada fase, mientras que las variables hemodinámicas no. Los parámetros electroencefalográficos son útiles para distinguir consciencia-inconsciencia durante las tres fases de la anestesia. El movimiento apareció para valores del BIS por encima de 58 y del LE90 por encima de 13 Hz, pudiendo indicar un nivel de hipnosis inadecuado. De la tercera parte del estudio podemos concluir que la adición de morfina al espacio peridural no reduce los requerimientos de sevoflurano pero si que provee una mayor calidad en la analgesia postoperatoria, durante la extubación orotraqueal. / Different monitors have been tried to evaluate depth of anesthesia, and the most extended are the cerebral monitors of electroencephalography (EEG).Objectives: To establish the EEG pattern and hemodynamic variations of the desflurane. To observe the EEG parameters, during induction, maintenance, and recovery. To establish the changes in the anesthetic concentration, administered to maintain a bispectral index (BIS) between 40-50, when morphine is added to peridural solutions.Matherial and methods: Twenty-four patients of gynecological surgery were monitorized with the EEG. Desflurane was administered at 0.5, 1 and 1.5 MAC. Hemodynamic variables and the EEG parameters, spectral edge frequency (SEF90) and delta ratio were collected. The second part of the study on 50 patients of abdominal surgery, hemodynamic values and EEG parameters were collected at: basal situation; before and after orotracheal intubation; after surgical incision; at 60 minutes; at 90 minutes; when anesthetic was withdrawn and BIS reached 60; when movement appeared; and at extubation time. Finally, on 40 patients of colloproctological surgery a thoracic peridural catheter was placed. Patients were randomized to receive morphine 0.1% (2 ml). Sevoflurane concentration was titrated to maintain a BIS between 40-50. Results: Blood pressure fell at 1.5 MAC, but heart rate did not. A significant decrease in the SEF90 appeared at 1.5 MAC, indicating a deeper plane of anesthesia. BIS values decreased from 95,6 to 34.7 and SEF90 fell from 20.5 to 11.9 Hz after anesthesia induction. During recovery mean BIS increased from 59.2 to 92,3 and SEF90 from 15.1 to 22.2 Hz, heart rate increased but blood pressure did not. The EEG values recorded when movement appeared were 77 for BIS (range 58-96) and 18Hz for SEF90 (range13.18). The only findings were that the morphine group had a lower pain score level than the bupivacaine group ( no pain on movement, 79% vs 31.5%, p<0.01).Conclusions: We can conclude that EEG processing provides a good measure of depth of anesthesia. EEG parameters are useful for distinguishing between the states of consciousness and unconsciouness during the three phases of anesthesia. Adding morphine to the epidural solution did not reduce sevoflurane requirements but did provide high quality postoperative analgesia.