INTRODUCTION
There is nothing more fundamental, personal or universal to humans than sex. Without it, none of us would be here. Sexual thoughts, desires and behaviours are part of daily life for many, occurring a little or a lot, but for others they barely exist, or perhaps linger only in a whisper and a tingle of memory. So what controls our sex drives and lives? It might feel like it’s our hearts, or even our genitals, but it’s our brains. Surprisingly, there has been very little research on how our brains do this. Despite our society being saturated with sexual images, the scientific study of human sexual behaviour is very limited compared to research into other human behaviours. What we know about how our brains control our sex lives comes from extrapolating from animal research, recent brain imaging studies, and observations of how sex drive and behaviour can change when a brain is damaged due to injury or disease. It is this final area of study that is the focus of this book. Certain parts of our brains play a crucial role in controlling our sex drives and sexual behaviour, in particular the frontal and temporal lobes and specific structures within them. If these brain regions are invaded by a tumour, or 1
deprived of oxygen during a stroke, or damaged in a motorbike crash, or disrupted by the neuropathology of dementia, your sexual behaviour could change radically: you could lose all interest in sex, you could be entirely consumed with thoughts of how to get more of it, or you could suddenly develop a new sexual interest or preference. Sex is typically not the ďŹ rst thing that comes to mind when you think of life after a traumatic brain injury or stroke, or during treatment for Parkinson’s disease, or in the early stages of dementia, but all these neurological conditions and many more can cause dramatic changes to our sex drives and lives. This is not a topic that is raised very often when dealing with these conditions, but it can have an exciting or devastating impact on our relationships. Doctors rarely discuss it, and patients may hesitate to bring it up when changes in the brain mean that so many other things need medical attention. But wanting too little or too much sex, or changing sexual preference, can devastate relationships and in rare cases even lead to criminal behaviour. For this reason, the sexual side effects of brain disorders need to be understood. When I decided to commit four years to a PhD in neuropsychology, I knew I had to choose a subject that I found intriguing and would keep me eager to learn more. It had to be related to patient care and have real-life implications. I hit the jackpot when I met with my future supervisor, who ran a rehabilitation clinic to support people with epilepsy who had undergone neurosurgery. She described how some of them had reported dramatic 2
SEX IN THE BRAIN
increases in their sex drive, known as ‘hypersexuality’. There were a few reported cases in the literature, but no thorough investigation of why this occurred in some patients. Was it a psychological reaction to sudden seizure freedom, or did it have something do with the part of the brain that was removed during surgery? I was hooked. I still am. I decided to write this book when I realised it had been nearly two decades since I completed that PhD research. I had the urge to share some case histories in the hope that it would bring this topic out of the bedrooms of those who have experienced changes in their sex lives through brain injury or disease and to the attention of all of us. This book is intended for intellectually curious readers who are interested in the brain and learning how brain disorders can impact on those most personal parts of people’s lives – their sex drive and behaviour. It is not an academic or scholarly work with all the answers to how your brain controls your sex life. Rather, it describes real cases of people who have experienced an alteration in their sex life due to brain injury or disease, and highlights some of the research on this topic. Some of the cases describe very rare sexual side effects of brain disorders or neurosurgeries, while others outline more typical sexual effects of neurological conditions. Fascinating, and sometimes funny or frightening, all the cases illuminate links between specific parts of the brain and sexual functions. For those with no personal experience of a brain disorder, I hope this book will provide unique insights into the experiences of people living with brain conditions. I INTRODUCTION
3
also hope this book provides comfort to those who have experienced sexual changes in the context of their neurological disorders, knowing that there are others who have felt the same. The patients and partners I interviewed for my research were so relieved to be able to discuss their situations, and to learn that others had experienced similar things. I can still recall a comment made by the husband of a woman who had the temporal lobe of her brain removed to relieve her of seizures. He was exhausted by her postoperative sexual requests, and incredibly – albeit jokingly – enquired whether he could have the same operation. ‘Can you give me one?’ he asked. ‘I can’t keep up!’
AS A CLINICAL NEUROPSYCHOLOGIST, I HAVE THE
privilege and luxury of spending several hours with my patients. This is typically an unusual experience for most people who are used to spitting out their symptoms to a rushed GP or medical specialist in under 15 minutes. When I conduct a neuropsychological assessment, I spend up to an hour taking my patient’s history – their story – with a focus on their cognitive or thinking skills, such as memory. It’s a bit like being a detective of the mind. I need to figure out if there has been any change in their cognition skills and, if so, what the changes are and why they have occurred. Sometimes the ‘why’ is already known, such as when someone sees me after having a traumatic brain injury in a car crash. At other times, the ‘why’ is the crucial question. A man in his fifties is struggling to find words 4
SEX IN THE BRAIN
and losing his train of thought in conversations. His driving has become erratic and he forgets to take his medications. Is he just stressed out, or is there something more sinister, like an early-onset dementia, occurring in his brain? If my patients come with a partner or another family member, I ask them for their views. Sometimes they are happy to talk about their loved ones in front of them; at other times they want to talk in private, sharing their worries and frustrations about this person who they feel they don’t know anymore. I ask about the patient’s schooling, their work and home lives, their mood and medical history. This luxury of time means that people often tell me things that they might not have shared with their other doctors. I don’t ever ask about their sex lives, but this doesn’t mean they don’t bring it up. I’ve had a patient tell me spontaneously about how she had sex with her father as a teenager and it was ‘a wonderful learning experience’; a man explain how he had learned from an alleged victim that his own father was a paedophile; and a teenager confide that while her mother thinks she is employed as a late-night cleaner, she is actually working as a prostitute in a local brothel. I’ve had the mother of a severely brain-injured young man explain how she comforted her son’s girlfriend after he told his girlfriend he didn’t like having sex with her as her ‘vagina was too loose’, and the carer of an elderly man tell me that since his brain injury he had begun discussing his previous sex life, particularly his love of ‘putting fingers up bums’. Usually INTRODUCTION
5
this information is a side story to what is most relevant to my cognitive detective work, but sometimes it is not. Sometimes it is the most prominent change in the context of a brain injury or disease. Each chapter of this book includes personal accounts from individuals who I have met in my clinical practice or research, or who have been described in the scientific literature. Through these case studies, I will describe what parts of the brain are implicated in sexual behaviours, what sex can actually do to our brains, and how love can alter and be altered by our brains. You will hear about the sexual side effects of neurosurgery, and rare cases of paraphilias – sexual arousal or interest in atypical objects or activities – that can manifest in people with brain injuries or disease, and how such cases raise complex questions for the criminal justice system. When I decided to become a clinical neuropsychologist, I certainly didn’t expect that I’d end up writing about sex, but I continue to be completely intrigued and intoxicated by this topic. I hope you are too.
6
SEX IN THE BRAIN
Praise for
SEX IN THE BRAIN “Sex in the Brain is an intoxicating read about our most important sex organ: the brain. Amee Baird’s book explores neuroscience in a way that is both accessible and engaging, and readers will be fascinated by the untold stories of how brain injury, illness, and disease impact our sex lives. They will walk away with a greater appreciation for the incredible diversity that exists in human sexual behavior and the way it is intricately controlled by the brain.” J U S T I N L E H M I L L E R , research fellow at the Kinsey Institute and author of Tell Me What You Want
“Baird has delivered an entertaining and informative tour of the sexiest bits of the human brain, with real case studies from her research and clinical practice. She captures the humanity of her patients, letting us into their lives and using their cases to unfold a better understanding of the brain and what it means to be human.” R O B B R O O K S , director of the Evolution and Ecology Research Centre, UNSW Sydney, and author of Sex, Genes, and Rock ‘n’ Roll
“The taboo on talking about changes in sex drive and sexual behaviors following brain damage is over! Neuropsychologist Amee Baird’s engaging case studies exploring this topic will move as well as educate the general reader and inspire professionals to incorporate this central human need into their patient assessments and treatments.” J E N N I O G D E N , author of Fractured Minds and Trouble in Mind
“A compelling overview of our current understanding of the brain mechanisms of sex, written in the tradition of Oliver Sacks.” M A R K S O L M S , director of neuropsychology, University of Cape Town ISBN: 978-0-231-19590-4
9 780231 195904
C O L U M B I A U N I V E R S I T Y P R E S S | N E W Y O R K | C U P. C O L U M B I A . E D U