Barry kicked off his dirty workboots by the front door. He grunted a greeting at his wife, Sue, as he made a beeline for the fridge, his mind focused only on the cold beer that awaited him. Sue sighed as she heard the creak of his recliner and knew that she was facing another night of the same old boring routine – of trying to engage her husband in conversation while he grunted replies at her, his eyes fixed on the TV screen.
It wasn’t what she had imagined their life would be like when they had met one hot New Year’s Eve in their twenties, when they had both laughed about their matching sunburned noses and jokingly called each other ‘Rudolph’. She wasn’t sure how much longer she could stand it. Barry was a grumpy and ungrateful husband. She tried to remember the last time he had made eye contact with her, let alone when they had last laughed together. Maybe it was when he gave her a kiss on the cheek just before he left on an interstate work trip a few months ago?
In an instant, that would all change.
Later that night, Sue woke to find Barry crying out in pain and clutching his head. He had suffered a stroke – to be precise, a subarachnoid haemorrhage due to a ruptured left posterior communicating artery aneurysm. Brain scans showed damage to the left hemisphere of his brain, in particular his left temporal lobe and basal ganglia, which had been scarred by blood and starved of oxygen.
I first met Barry and Sue three months afterwards. Surprisingly, considering he had experienced a major stroke, Barry said he did not have any complaints except for some occasional word-finding difficulties. He smiled and told me he felt great. ‘Better than ever,’ he said. ‘It’s weird!’ When I asked if I could speak with Sue alone, he kissed her on the hand and said, ‘See you soon, my love.’ She laughed and looked shyly at me.
After the door closed and we heard his footsteps fade away down the hallway, Sue revealed the colossal shift in their relationship. ‘It’s marvellous how this has changed him,’ she told me. ‘He’s done a one-eighty! He’s happy all the time, enjoying life, laughing more. He loves everything now. He’s different – it’s a new version of the old Barry. He’s always saying how much he loves me, and “You’re beautiful.” It’s wonderfully overwhelming.’ Barry had unexpectedly transformed into the romantic husband she’d always hoped for, a man brimming with joy and constantly professing his love for his wife. His burst brain aneurysm had saved their marriage.
It is rare for anyone affected directly or indirectly by a brain injury to consider it a positive thing, but if it resulted in enhanced love, and a more loveable version of the person you knew before, who wouldn’t consider it a blessing? Barry’s case raises obvious questions. Are there certain brain regions that are crucial for love? Were these regions somehow ‘released’ by Barry’s subarachnoid haemorrhage? Are these parts of the brain the same as the ones that are involved in the sexual neural network? In other words, do the same parts of the brain influence sex and love?
THE FEELING OF ROMANTIC LOVE – FALLING IN OR OUT of it, being in it or losing it – is a distinctive and unforgettable human experience. Love is one of the most common themes in songs, films and literature. Songs tend to refer to the heart as the organ of love, but really we should be singing about the brain. I guess singing about having your brain broken, or brainache, or a burning love that springs from the bottom of your brain doesn’t quite have the same effect.
Love can consume and devastate us; it can bring about life or make us want to destroy it in a jealous rage. It is a universal emotion, thought to have existed across all cultures since humans first evolved. Biological anthropologist Helen Fisher, a leading researcher in this area, proposes that romantic love evolved to motivate our ancestors to focus on and conserve energy for a specific mating partner, leading to attachment and the benefits of mutual parenting. She considers love to be a natural ‘addiction’ and highlights how people who are in love or rejected in love show the same symptoms as those with substance (such as amphetamines) and behaviour-related (such as gambling) addictions. Craving, mood changes and, in the case of a break-up, withdrawal sypmtoms are common to all these addictions.
Fisher’s theory that equates love with addiction is supported by neuroimaging studies that have examined the brains of people in love while they look at pictures of their romantic partner. Using functional MRI brain scanning techniques (fMRI), which measure blood flow, researchers have identified brain networks related to romantic love that overlap with parts of the brain involved in our neural ‘reward system’. Our brains respond to rewards by producing the neurotransmitter dopamine (see Chapter 2), and the dopamine neural pathways are part of the reward system. The mesolimbic pathway connects the ventral tegmental area (one of the main dopamine-producing structures) with the ventral striatum of the basal ganglia; this, in turn, has extensive links with frontal brain regions. Brain scans of people in love have revealed activation or increased blood flow to parts of the frontal lobe (such as the anterior cingulate cortex), basal ganglia (nucleus accumbens and caudate nucleus) and hypothalamus – brain regions that not only process reward but are also associated with substance and behavioural addictions, including the controversial porn and sex ‘addictions’ (see Chapter 9). This overlap provides support for Fisher’s ‘love as an addiction’ theory.
The regions activated in these loved-up brains also overlap with many crucial parts of the sexual neural network, such as the amygdala and prefrontal cortex, but both romantic love and sexual neural networks are widespread and involve structures throughout the brain. Brain imaging can only reflect a snapshot of time, and cannot possibly capture the complex experience of sex or love. It can, however, provide some intriguing insights into the brain regions that are involved in both.
Amazingly, different patterns of activation and functional connectivity between brain regions have been found when comparing people in and out of love, and those who have never been in love. Even when the brain is ‘at rest’ or ‘in neutral’ – that is, not engaged in a particular task (such as staring at a photo of a lover) – there are differences in the brains of people who are in or out of love. A part of the frontal lobe (specifically, the left dorsal anterior cingulate cortex) shows differences in ‘regional homogeneity’, or synchronised neural activity, depending on whether you are in or out of love, and how long it has been since you experienced love. People who are ‘in love’ have increased left dorsal anterior cingulate regional homogeneity or neural activity that is more ‘in synch’. Surprisingly, this is positively associated with the length of time they have been in love, so it is greater in those who have been in love for a longer period of time than for those experiencing the first flush of new love. On the other hand, for those out of love, the longer it has been since a break-up, the less regional homogeneity will be found in left dorsal anterior cingulate cortex.
Furthermore, when people are in love, their brains display increased functional connectivity – that is, an increase in spontaneous blood-oxygen-dependent signals between spatially remote regions and networks of the brain. When we are in love, this functional connectivity increases between the regions that are involved in reward, motivation and emotion regulation (such as the amygdala), and in social cognition, or the types of thinking skills required to negotiate social relationships (such as the medial prefrontal cortex and temporal lobe). So in a ‘chicken and egg’ kind of way, it seems that love enhances the patterns of activation within brain regions that control the very functions that you need to feel love! These research findings suggest that a brain scan might be able to prove if people really are madly in love, or if they have never really been in love at all.
Patterns of brain activity that occur early during a period of romantic love can even be used to predict whether a relationship will last. In one study, people experiencing the early phase of romantic love had fMRI scans; then, 40 months later, they were rescanned. The brain activation patterns of those who were still in their relationship were compared with the patterns in those who had broken up. People who were still with their partners actually showed less activation in their first scans in frontal regions of the brain (specifically, the medial orbitofrontal cortex and right subcallosal cingulate) and the basal ganglia (right nucleus accumbens) when compared with those whose relationships had ended. Incredibly, they found the less activation in those brain regions early in the relationship, the greater their relationship satisfaction later in the relationship. So there is preliminary evidence from this study that your brain activation early in your relationship can predict your relationship stability and satisfaction 40 months later. If your brain activation is through the roof in the early stages of getting together, it may be an omen for the future of your relationship!
The neuroimaging studies of the brain in love discussed so far have been ‘functional’ studies of blood flow and glucose metabolism. There has also been a study of the neural implications of love that has looked at the structure of the brain. Compared with single people, those in the first month of a romantic relationship have been found to have reduced grey matter density, which reflects the loss of certain parts of neurons, in the right ‘striatum’. This is part of the basal ganglia and includes structures, such as the caudate nucleus, which are part of the reward neural network (see Chapter 9). People in a relationship scored higher on a subjective questionnaire of happiness, and the authors suggested that this positive experience of being in the early stages of a romantic relationship could lead to structural brain changes. Nevertheless, this study cannot tell us about the causal connections between these two factors. It may be that people with reduced right striatum grey matter density are just more likely to have a romantic relationship, rather than the romantic relationship causing this brain change. To investigate causal changes of romantic love, we need a longitudinal study involving brain scanning before and after a romantic relationship. Maybe researchers should start advertising on Tinder to find willing participants…
But what about the brains of people who have fallen out of or been rejected in love? The idea of a ‘broken heart’ makes direct reference to the fact that a romantic break-up can cause physical pain. Losing love is a feeling that most people will experience at some point in their lives and never forget. Like grief and depression, it can cause a range of physical symptoms, from reduced appetite to sleep difficulties. Brain imaging studies of people who are ‘brokenhearted’ have found that romantic rejection and physical pain activate the same brain regions, specifically the anterior cingulate cortex and the anterior insula. One study found that these brain regions were activated when people viewed pictures of a person who had recently broken up with them, and when they were given painful heat stimulation. Therefore, the experience of romantic rejection and physical pain are underpinned by the same neural regions. ‘Heartbreak’ might be an anatomically flawed idea, but it does reflect the physical pain that people can experience when love comes to an unhappy end.
IT IS NO SURPRISE THAT THE NEURAL NETWORK UNDERlying romantic love is as complex as love itself. Love involves the full array of human emotional and physical experiences, so it makes sense that it is mediated by widespread brain regions that overlap with the sexual, reward and pain neural networks. We can also learn about brain regions that are involved in love from two fascinating types of delusions that can occur in the context of brain injury or disease: erotomania and Capgras delusion. Erotomania, also known as De Clérambault’s syndrome (after the French psychiatrist who first described it), is the sudden belief that someone of higher social status has fallen passionately in love with you, and that you are deeply in love with them. It typically manifests in middle-aged females with psychiatric illnesses such as schizophrenia or bipolar disorder, but there are rare reports of it occurring after an acquired brain injury or in people with dementia. For Margaret, it was the first symptom of a sinister problem.
Margaret was 65 years old. She had two children, and had lived alone since her divorce. Her medical history included a transient ischaemic attack – a brief and temporary interruption of blood flow to the brain. These are often a warning sign that you are at risk of having a stroke. She had been a heavy smoker, working through up to 40 cigarettes a day, but had quit five years before she developed the psychiatric and neurological problems that brought her to the attention of the authors of her case study.
Over a period of six months, Margaret became increasingly obsessed with a deceased American singer of the 1940s and ’50s, Dick Haymes, who was famous for his love ballads and his marriage to actress Rita Hayworth. Margaret bought every CD and DVD she could find that featured Haymes, and his music was a constant soundtrack to her life, broadcasting across her entire house from devices in all rooms. Despite being told he was dead, she insisted the singer was alive, and believed he was living next door to her and was in love with her. She said she ‘loved him to bits’ and on one occasion she waited for hours outside her home, anticipating his arrival. When her daughter challenged her about her apparent delusion, Margaret slapped her in the face, something she had never done before.
Her daughter discovered her mother had not been eating or sleeping properly, and a neighbour told her he had seen Margaret wandering the streets late at night. She insisted on taking Margaret to the doctor. The doctor sent her for an MRI brain scan which revealed chronic small vessel ischaemia – brain changes related to a lack of oxygen to the small blood vessels in the brain, often found in heavy smokers – and atrophy, or shrinking, of the anterior (front part) of the temporal lobes. A brain scan called a SPECT (single photon emission computed tomography), which measures glucose metabolism, showed hypoperfusion, or reduced metabolism, in the left frontal and temporal regions. This means that those brain regions were not functioning properly and, as we know, those regions control a vast array of functions that essentially make us who we are – and they are also considered part of the sexual and love neural networks. Her neurological condition had left Margaret unable to interpret one of our most complex social behaviours – love.
She was started on antipsychotic medication and her erotomania resolved, but other symptoms started to appear. Her speech became slurred and soft, her tongue twitched intermittently and she had difficulty swallowing. The muscles in her hands wasted away, and she had to abandon knitting, her favourite hobby, as she couldn’t hold onto the needles anymore. She lost weight and her legs became weak. Eighteen months after she had been seen for her erotomania, she was sent for an urgent neurological review. During her appointment, she was impulsive and demonstrated ‘utilisation behaviour’ – or a tendency to use any object placed in her vicinity, like a baby grabbing at toys on their highchair table. This is indicative of severe frontal lobe dysfunction. She grabbed the neurologist’s pen from his desk and started writing on his notepad, and leaned forward and reached for the glasses that protruded from his shirt pocket. During a neuropsychological assessment she had to be physically restrained to stop her from grabbing at objects on the desk. She had difficulty concentrating and could only comprehend very simple sentences. After a series of investigations, she received a diagnosis of motor neurone disease with frontotemporal dementia. Motor neurone disease was initially thought to only affect nerve cells controlling the muscles, but it is now known that it can also cause changes to cognition and behaviour in up to half of the people who are diagnosed with the condition. In some cases like Margaret’s – an estimated 5–15 per cent of those diagnosed – these changes will be severe enough to warrant a diagnosis of behavioural-variant frontotemporal dementia as well.
In Margaret’s case, erotomania was the first sign of the changes that were occurring in her brain as a result of a tragic neurodegenerative condition. In the case of Samantha, introduced in Chapter 5, erotomania came three years after her right temporal lobe was damaged by an intracranial haemorrhage that occurred during sex. Samantha was by this time 29 years old, and she had begun to experience paranoid delusions of great concern. One was that people were spying on her and trying to kill her. Another was her passionate desire and love for her real estate agent, from whom she had rented a flat. She believed he was in love with her and wanted to marry her, but that he was prevented from doing so by the government. He maintained that all he had done was organise her lease. She stalked him, sending numerous letters and calling him hundreds of times, to the extent that he moved to a different city to flee her persistent attention – only to find that she had managed to track him down again. The case report stated that Samantha’s paranoid delusions resolved with medication, but her erotomania remained unchanged. There is no other information about what happened to Samantha. Her case is a tragic and very rare example of how sex can change your brain, and your brain in turn can alter your sex and love life forever.
Another group of delusions, called ‘misidentification delusions’, involve the belief that a familiar person, object or place has been altered. These types of delusions typically occur in psychiatric conditions such as schizophrenia, and in neurological disorders including Alzheimer’s dementia. A dramatic example of this is Capgras delusion, when a person believes that a significant other – typically a spouse – has been replaced by an identical impostor. In other words, their feeling of familiarity or love for the person vanishes. It could be characterised as a sudden falling out of love, the flip side of erotomania.
Barbara was diagnosed with Alzheimer’s dementia five years before I met her. She would often get confused and agitated. On some occasions, she would even fail to recognise her husband, David. It would occur suddenly and out of the blue. For example, if she left David to go to another room, on her return she would ask him, ‘Who are you? Where’s David?’ and order him out of the house. These episodes typically lasted between one and three hours. Her husband would go outside, sit in his car and wait. On one occasion, she said, ‘Don’t go and sit in the car – that’s David’s car.’
Whenever this happened, David had no idea how to make Barbara understand that he was her partner of nearly 60 years. He told me that after this first occurred, he decided to sleep in a different bed, as he did not want to frighten her. No doubt it would have been terrifying for both of them if she had awoken in the night, in the midst of a Capgras delusion, believing that an intruder was lying next to her. David now claims that it was the power of a love song that resolved this delusion and brought Barbara back to him. On the night they first met, they had danced to the last song of the evening, ‘Unchained Melody’. He began singing this to her several times a day, and within a couple of weeks, he said, ‘She came back. Everything changed. It worked quickly. She stopped sending me away, and became my shadow.’ The episodes of her failing to recognise him stopped occurring. Barbara and David had heeded the lyrics: ‘I’ll be coming home, wait for me.’
Music is a powerful treatment tool for symptoms of dementia, and songs from people’s younger days can take them back in time to their first loves, even if only for the duration of the song itself. In the midst of the multitude of challenges of caring for someone with dementia, such moments remind our loved ones who they were, and the relationships they have. With no cure for dementia, maximising these moments is crucial.
Just as our brains can change or be changed by sex, love also alters and is altered by our brains. Brain injury or disease can make us fall in or out of love in sudden and dramatic ways. We do not fully understand the complexities of love; likewise, there is still so much more to learn about love in the brain.
AFTER MONTHS OF REHABILITATION, BARRY EVENTUALLY returned to work. When he returns home each evening, the first thing he does is kiss Sue, ask how her day was, and tell her that dinner smells delicious. The days of grumpy pre-stroke Barry are long gone, and Sue is thankful for the change that gave her a loving husband. I never asked about their sex life, but I have no doubt it improved. His stroke caused extensive damage to the left hemisphere of his brain, including the left frontal and temporal lobes, which we know are part of both the love and sexual neural networks. The positive outcome of his brain injury could also be due to it affecting the left side of his brain, leading to an improvement in the expression and experience of all positive emotions, not just love. In a study of people with frontotemporal dementia, those with greater left frontal atrophy were found to show increased expressions of happiness in response to a film. The authors of this study proposed that selective damage to left frontal brain regions may weaken positive emotion regulation and correspondingly facilitate positive emotional responses – or expressions of happiness. This extends earlier research that suggested the left frontal lobe is involved in generating positive emotion, and indicates that damage to this area may actually enable positive emotions to be expressed.
Dustin is the only other patient I have seen with a severe brain injury who reported an exclusively positive outcome. He also had extensive left hemisphere damage, but his was the result of a very severe traumatic brain injury he had sustained in an assault. Before his injury, he had a long forensic and psychiatric history, including a diagnosis of antisocial personality disorder. Remarkably, when I spoke with him, he told me that his brain injury was ‘a good thing’: ‘Before it, [I was] an arsehole. My kids hated me and I did bad things. Now they love me.’ His mother also remarked, ‘This injury was the best thing that happened to him. He’s a much nicer person now.’
In the cases of both Dustin and Barry, their left-sided brain injuries enhanced their ability to express positive emotions, including love. This resulted in them being generally much nicer guys who were more pleasant to be around, enabling happier social relationships. Luckily, both expressed their newfound positivity and love in a socially acceptable ways. Sometimes, however, a brain injury or disease can release a sexual or love interest in something other than a consenting human partner, which can lead to devastating outcomes for the patients and their family members. These paraphilias are discussed in the next chapter.