A thorough knowledge of gross human neuroanatomy is important in understanding basic and clinical neuroscience. In this chapter we describe the key anatomical features of the human brain followed by a discussion on the main developmental processes and signaling mechanisms of neurogenesis and embryology. Finally, we introduce the reader to different model organisms commonly used in neuroscience research.

Brain tumors in adults and children range from devastating malignant tumors with a dire prognosis to benign tumors that can be totally resected with a favorable outcome. The incidence rate for primary brain tumors in adults in the United States is approximately 23.8 per 100,000 persons. Of those, approximately two thirds are benign or borderline in nature. The most common benign tumor in adults is meningioma. The incidence in the pediatric population is approximately 6.1 per 100,000 children. However, the incidence of malignant brain tumors is higher in children than adults. We discuss the most common benign brain tumors in adults followed by a discussion on pediatric brain tumors.

Hydrocephalus affects 1/1000 births and is treated using neurosurgical cerebrospinal fluid(CSF) diversion techniques with high complication and failure rates. Recent data on the pathogenesis of acute post-hemorrhagic hydrocephalus(PHH) have implicated an acute Toll-like receptor(TLR4)-dependent hypersecretory response of the choroid plexus epithelium(CPe), the site of highly regulated CSF production and part of the blood–CSF barrier. Post-infectious hydrocephalus(PIH) is the most common form of hydrocephalus worldwide and shares multiple features with PHH, including TLR4-regulated CSF cytokines and immune cells. We introduce the concept of “inflammatory hydrocephalus”, and argue this may more precisely convey the shared pathogenic mechanisms and potential therapeutic vulnerabilities of PHH/PIH than the current concept of “secondary hydrocephalus.” This change of emphasis could shift our view of PHH/PIH from that of lifelong neurosurgical disorders to one of preventable neuroinflammatory conditions. In addition to attenuating acute CPe hypersecretion, early targeting of TLR4 may prevent inflammation-induced brain damage resulting in scarring, obstruction, and poor long-term neurodevelopmental outcomes.

The immune system is a complex system that works to recognize and eliminate foreign antigens – any protein, carbohydrate, lipid, deoxyribonucleic acid, or small organic molecule that can produce an immune response – from the body, and is divided into two subdivisions: the innate immune system and the adaptive immune system.

Artificial intelligence(AI), a term first coined by John McCarthy in the 1950s, is best thought of as the design of intelligent agents that can recognize and process stimuli to make decisions, similar to humans. The use of AI and artificial neural networks(ANNs) in medicine has been widely adopted to improve the efficiency of diagnostic medicine, and these include ANN-based analysis of electrocardiograms, electroencephalograms, radiographs, and automated computerized systems based on ANNs for detection of cancer data.

Craniosynostosis is a condition associated with the pathologic premature fusion of one or more cranial sutures. Physiologically, the metopic suture closes in infancy, while the remaining sutures close years later, even into adulthood. In craniosynostosis, characteristic calvarial deformity first appears on ultrasound in the second trimester and precedes identifiable suture fusion by 4–16 weeks. When this premature closure occurs, it is associated with restriction of calvarial growth perpendicular to the fused suture, with compensatory increase in growth at the remaining sutures. Previously there was debate as to whether the suture fusion itself drives this restriction of growth, or whether a cranial base deformity drives the abnormal development through tension bands in the dura. Currently there is a preponderance of evidence from human and rabbit studies supporting the idea that suture fusion is at least a significant contributor to the overall skull shape abnormality. The natural history of the disease is such that the deformity observed in infancy increases in severity if not surgically corrected.

Vascular neurosurgery is a diverse field focused on surgical and interventional treatment of cerebrovascular disease. Given this diverse disease pool vascular neurosurgery spans multiple fields, including neurology, cardiology, intensive care, interventional radiology, and clinical genetics and can affect involve both adult and pediatric patents. Despite extensive basic and translational research into the pathophysiology of cerebrovascular disease very few treatments have been successfully implemented into clinical practice. In this chapter we review the animal models used in the study of the pathophysiology of subarachnoid hemorrhage and its sequelae, such as early brain injury and delayed cerebral ischemia, highlighting the challenges and future direction. Furthermore, we will also discuss the animal models used to elucidate the mechanisms behind aneurysm formation.

The somatosensory system is responsible for sensation such as touch. It is a subset of the sensory nervous system that represents the visual, olfactory, auditory, and gustatory pathways discussed in Chapter 6. There are five types of somatosensory receptors: mechanoreceptors, proprioceptors, pain receptors, thermoreceptors, and chemoreceptors.

Viewing the neuron as an electrical system gives an easy handle into modeling the generation and transmission of action potentials. In the simplest version of this framework, the entire neuron can be viewed as having a single membrane potential. Models built on this assumption are termed “single-compartment” models. A more detailed assessment of the spatial variation in membrane potential gives rise to “multi-compartment” models. We now look at the basic electrical properties of spiking neurons that are essential to most models

Functional neurosurgery is the branch of neurosurgery that seeks to restore or improve neurologic function by manipulation of neural activity. Here we provide a brief review of the pathobiology of the disease processes functional neurosurgery addresses: movement disorders including Parkinson’s disease, essential tremor, and dystonia, epilepsy, chronic pain, and psychiatric diseases including obsessive compulsive disorder, depression, and addiction. We also review emerging applications of neurosurgical techniques including deep brain stimulation not yet prevalent in clinical practice including brain–computer interfaces and disorders of consciousness. Finally, we discuss emerging technology likely to be useful in this rapidly advancing field, including high-density neural recordings, gene therapy, optogenetics, and stem-cell therapy.

As we will learn, cognitive neuroscience had very humble beginnings back in the time of the Romans, and was essentially dormant for close to two millennia thereafter. A surge of interest in anatomy, and the brain in particular, overtook scientists in Europe in the mid-1800s, pushing the field forward. This time period coincided with interest in mapping brain structure to function and description of brain circuits that form the foundations of cognitive neuroscience today. The need to serve the veterans of two World Wars, encompassing regions across the planet, led to a worldwide examination of the behavioral consequences of brain damage. Toward the end of the twentieth century and continuing on until today, an explosion of methods has allowed scientists for the first time to link brain structure and function to mental function in neurologically intact people.

The life story of Muhammad Ali (Figure 4.1), one of the twentieth century’s most famous boxers, interweaves not only boxing and politics, but also the neural basis of motor control. Ali, who was known as Cassius Clay before his conversion to Islam, rose to prominence as an Olympic boxer, eventually turning pro and becoming a world champion. Ali said that his boxing strategy was to “float like a butterfly, sting like a bee,” meaning that his fancy footwork allowed him to flutter around the ring, evading his opponents’ punches until he could move in for a knockout. At the height of his career, Ali was drafted to serve in the US armed forces in Vietnam, but he refused induction because of his religious beliefs. Convicted of draft evasion, he was stripped of his boxing crown and not allowed to box in a sanctioned match for the next three years.

In this chapter, we consider different definitions of bilingualism, underscoring the reality that there are various aspects which should be taken into account when investigating bilingualism, particularly when designing studies and choosing participants. Bilingualism is a complex construct and should be viewed on a continuum. Crucially, many key details about bilinguals’ backgrounds need to be reported in studies to make results comparable and clearly linkable to the specific study sample. Relative proficiency level seems to be the most influential factor, but it is by no means the only factor relevant for studying bilingualism. Rather, individual differences and their variability, dynamically related dimensions and their interaction over time, speech environment and their changes, language use habits, socioeconomic background, and so on have been reported to influence language processing and even brain function to some extent.

The seemingly bizarre behavior displayed by the gentleman in this story can be attributed to a syndrome known as hemineglect or, in its less severe forms, hemi-inattention. Despite having intact sensory and motor functioning, people with hemineglect do not pay attention to one side of space. Hemineglect is considered to be mainly a spatial phenomenon, because the neglect of information occurs with reference to a spatial frame (i.e., information contralateral to the lesion is ignored) and because all types of information, regardless of modality, on the neglected side of space are ignored. Given what you learned in Chapter 7 about the important role that the parietal lobe plays in spatial processes, it should not surprise you that hemineglect often involves damage to the right parietal lobe.