Freud, the Subconscious and Virginia Woolf

Abstract

Sigmund Freud, a founding father of twentieth century psychiatry, was born in 1856 in Freiberg, situated in the Austrian Empire (Fig. 3.1). He was a brilliant student at school and during his medical degree at university, showing precocious intellectual and observational powers. These were such that by the time he was 22 he had discovered, through extraordinary technical skill and perseverance in dissecting out neurons in lamprey and crayfish, that neurons are individual cells and not parts of a continuous syncytium of cells (Fig. 3.2a, b). This work places him with Ramon y Cajal as co-discoverer of the neuron. Freud then went on to make seminal contributions concerning the identity of groups of neurons in the medulla oblongata of the vertebrate nervous system and the arrangement of the nerve tracts in this part of the brain, applying his technical skills to early developing fetal brains for ease of dissection and identification. By the early 1890s Freud was making contributions to neurology such as in his On Aphasia (1891), which emphasizes the distinction between an organic aphasia and the condition of hysterical speech, as well as in his ‘A Psychology for Neurologists’ in which he attempted to distinguish between normal and pathological activities of the mind on neurological grounds. In his 1893 work, Diagnostisches Lexikon für praktische Ärzte, he identified four areas of the brain in which lesions give rise to disorders of speech (Fig. 3.3), and made the very important distinction that although such lesions can be localized anatomically, functions cannot. This marks the departure of Freud from clinical neurology to psychiatry, for he then realized that the functional changes in the cortex giving rise to neuroses that he observed in his patients could not be localized to distinct areas that have by one means or another been lesioned. No pathological anatomy could be identified as underlying clinical observations on mood disorders and neuroses. In this case only careful clinical observations could be made to infer hypothetical relations between, for example, pathological mood conditions and sexual activity, as illustrated in the sketches he drew for his friend Wilhelm Fleiss in 1894 (Fig. 3.4a). However Freud still attempted from time to time to give a neuronal network account of his psychiatric observations, as in a description of how repressed memories might arise in the 1895 manuscript, Entwurf einer Psychologie (Project for a Scientific Psychology). Here he provided a neuronal model illustrating how repression might work, reproduced in Fig. 3.4b. A particular perception or sensation, represented by impulse firing of neuron ‘a’, normally activates the lower neuron representing a hostile memory giving rise to feelings of ‘unpleasure’, a neuron which Freud called the psi (mnemic or mnemonic) neuron. This is prevented by a process that he referred to as ‘side cathexis’ which diverts the impulses away from the mnemonic neuron via the upper pathway (alpha, beta, gamma, delta pathway), through a series of what we would now call synapses (each indicated by short parallel lines), so the hostile memory is repressed. The use of a hypothetical neural network to elucidate possible functions that are at play in the cortex in mood disorders such as depression has become a hallmark of twenty first century neuropsychiatry, as we shall see in Chap. 5. Freud may be regarded then not only as a founder of the neuron doctrine, but also of the use of neural networks to unravel what has gone awry with cortical functions implicated in psychiatric disorders.