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This chapter discusses the emergence of dominant ideas about motor cortex. It traces motor cortex research from its beginning to motor maps of Penfield and Boldrey (1937) and Woolsey et al. (1952). This segment of the history is mainly about electrical stimulation applied to the surface of the cortex. Using this technique, researchers drew motor maps of greater and greater elaboration. After Penfield and Woolsey, more fine-grained techniques such as microstimulation and single-neuron recording were used to probe the details and reopened all the same questions and debates.

This chapter considers possible defenses of the claim that the conscious aspects of experience supervene on the experiencing subject's brain. Considerations discussed include the very occurrence of hallucinations, thought experiments, brain stimulation experiments, and facts about the way the brain processes visual information. It is then shown how the theory of hallucination presented in Chapter 4 can explain conditions such as akinetopsia and achromatopsia and how the ‘binding problem’ can be solved. The chapter concludes with an explanation of how this theory can accommodate the intuition that a subject whose brain was artificially stimulated in exactly the same way as it would have been stimulated in a veridical case would have an utterly convincing hallucination.

The papers published by Milner, Scoville, and Penfield on the effects of bilateral temporal lobectomy have had a profound influence on the neuroscience of memory. This chapter addresses the following questions: Why did those papers have the impact they did, where their precursors did not? What were the major findings? What were the effects of excisions of structures other than those in the temporal lobes? How do the initial findings hold up over the years? It concludes by noting that the influence of these papers is still being felt, and that some of their findings and conjectures, which did not receive much attention at the time of publication, now provide relevant insights on the nature of hippocampal-neocortical interactions and their effects on a variety of memory phenomena and their theoretical significance.

This chapter charts the transformation of Foerster's practice in the work of Wilder Penfield. Penfield came to study with Foerster in Breslau in 1928 and brought Foerster's epilepsy operation back to North America. There it formed the basis of Penfield's clinical work. In contrast to Foerster, Penfield re-tasked his operation technique in order to map the brain. I argue that the reemergence of the localization project after a thirty-year hiatus can be explained by Penfield's de-composition of the reflex. Like Schilder, Penfield tested both sides of the reflex arc separately, studying in turn sensory and motor responses. As such Penfield could sideline the systemic aspects of the reflex that had structured earlier investigations and made localization so unconvincing. And like Schilder, this encouraged Penfield to posit a self-transparent patient who could provide insight into sensory states. As this chapter shows, the self-transparency of Penfield's introspective patient increasingly became the focus of his research, as in the 1950s he concentrated his efforts on tracking down an ever-elusive “mind.” 168

This chapter considers the work of Canadian neurosurgeon Wilder Penfield, who contributed more than anyone to the theory that our brains contain a complete record of everything we have ever experienced. Based on several brain stimulation studies on patients with epilepsy, Penfield declared that our brains store away experiences “like a wire-recorder or a tape-recorder.” Current brain science has dispensed with the notion that Penfield discovered a neuronal tape recorder. Nonetheless, his theory has embedded itself in the collective memory, where its lies next to other favorite neuromyths such as “we use only 10 per cent of our brains,” or “women are better at multitasking because they have more connections between the two halves of their brains”—myths that are believed not because the evidence is convincing but because people want to believe them.

Neurosurgery provides rare opportunities for learning and better understanding of the brain in ways that are not available in any other field of neuroscience. These opportunities hold unusual promise for future patients and for development of better tools to meet the challenges posed by neurological afflictions. Here, we review neurosurgical procedures suitable for research: electrical stimulation, epilepsy surgery, deep brain stimulation, and brain-machine interfaces.

Chapter 9 discusses the rare phenomenon of musical hallucinations. For some they are unwanted, persistent, and dramatically intrusive. Others hear phantom music that is sophisticated, beautiful, and sometimes original. People often describe their hallucinated music in terms of “playlists” composed of music in many different genres, from which fragments seem randomly selected. One such playlist might include folk songs, religious hymns, Christmas carols, patriotic songs, and children’s songs. The music often sounds as though played on a scratched or broken record, or on a tape constantly being rewound. Musical hallucinations are most likely to be experienced by elderly people with hearing loss, but young people with normal hearing, including excellent musicians, also experience them. Some may be caused by an unusually large amount of brain activation, particularly in the temporal lobe. People who have been isolated for long periods may also experience hallucinations, including of music. Hallucinations of speech are also described and discussed. Reports of musical hallucinations show that the different attributes of music can be retrieved or lost independently. A hallucinated piece might be heard in the wrong tempo or loudness, or as played by an unknown instrument. Famous musicians who hallucinated music include Robert Schumann, Bedřich Smetana, and Sviatislav Richter.