From methods to meaning in functional neuroimagingReinders, A. A. T. S. 2004 s.n.. 200 p.
Research output: Thesis › Thesis fully internal (DIV)
A major challenge in the ﬁeld of neuroscience is to understand the biological basis of emotion, cognition, and, ultimately, consciousness. Exploring the science of the mind involves studying the brain. The brain is part of the nervous system, which is a communication network that allows an organism to interact with its environment. The environment includes both the external environment (theworld outside the body) and the internal environment (the contents of the body) (Willes, 1993). The human nervous system can be subdivided into a peripheral and a cen-tral part. The peripheral nervous system controls voluntary muscle movement (somatic part) and involuntary muscle movement (autonomic part). The central nervous system (CNS) contains the spinal cord and the brain. The CNS is a mech-anism that ensures the coordination of the actions in a part of the body with the actions in all other parts of the body. The CNS integrates internal and external environmental information to enable human behavior (Kalat, 1999a;Willes, 1993). The brain consists of billions of neurons. Neurons transmit information from one location, e.g. brain area, to another location in the shape of electrochemical impulses. These impulses, the so-called action potentials, are transmitted by the neuron via dendrites (taking care of the information input) and axons (taking care of the information output). Axons are usually covered with a myelin sheath to quicken the information transmission (Kalat, 1999b). An action potential may in-volve one single neuron; however,more often clusters of neurons ﬁre. Information from ﬁring clusters is propagated through neuronal networks to establish a brain function. Neurons in the brain need to function both locally (interactions between neighboring neurons) and globally (interactions among distant brain areas) to make human behavior possible. Neuronal activity can be investigated using direct measurement, indirect mea-surement or a combination of both (Horwitz and Poeppel, 2002; Momjian et al., 2003). Directmeasurement involves single cell recordings that are performed only chieﬂy in animal experiments. In humans, this is only possible during neuro-surgery. Therefore, non-invasive procedures, i.e. indirect methods, are employed in man. These indirect methods comprise electromagnetic source imaging and measurements of metabolic changes. Electroencephalography (EEG) and magne-toencephalography (MEG)measure the electromagnetic signal caused by neuronal ﬁring, whereas positron emission tomography (PET) and functional magnetic res-onance imaging (fMRI) measure physiologic or metabolic changes that are due to neuronal activity in the brain. To summarize, a broad spectrum of techniques is available tomeasure human brain activity (Horwitz et al., 2000).
|Qualification||Doctor of Philosophy|
|State||Published - 2004|
- 44.90 neurologie, Proefschriften (vorm), Hersenen, Beeldverwerkende diagnostiek
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