In the philosophy of memory, singularism is the view that episodic memories are singular mental states about unique personally experienced past events. In this paper, I present an empirical challenge to singularism. I examine three distinct lines of evidence from the psychology of memory, concerning general event memories, the transformation of memory traces and the minimized role temporal information plays in major psychological theories of episodic memory. I argue that singularist views will have a hard time accommodating this evidence, facing (...) a problem of transitional gradation. I then look at some potential consequences for the larger debate, highlighting the way in which singularism has featured in three important recent arguments in the philosophy of memory. (shrink)

Why do we sleep? Loosing consciousness makes us completely vulnerable to any dangers of the environment for a third of our life time and must therefore yield a critical evolutionary advantage. A likely core function of sleep is the regulation of neuronal plasticity. The absence of interfering conscious information processing sets the stage for the basic maintenance of synaptic homeostasis to the complex reorganization and consolidation of memories. However, the underlying neuronal mechanisms subserving these processes are still largely unknown. The (...) aim of this thesis is to further elucidate the essential role of sleep-specific neuronal oscillations in brain plasticity. In a multimodal neuroscientific approach, non-invasive imaging methods (EEG and fMRI) and brain stimulation techniques (TMS and tDCS) are combined in a series of empirical studies to investigate how slow oscillations and sleep spindles are influenced by and in turn mediate plastic changes in the sleeping brain. (shrink)