1. Brain architecture alters to compensate for depression

    March 22, 2017 by Ashley

    From the Children’s Hospital Los Angeles press release:

    A study led by Ravi Bansal, PhD, and Bradley S. Peterson, MD, of The Saban Research Institute of Children’s Hospital Los Angeles, has found structural differences in the cerebral cortex of patients with depression and that these differences normalize with appropriate medication. The study, published in Molecular Psychiatry on March 7, is the first to report within the context of a randomized, controlled trial, the presence of structural changes in the cerebral cortex during medication treatment for depression and the first to provide in vivo evidence for the presence of anatomical neuroplasticity in human brain.

    “Our findings suggest that thickening of the cerebral cortex is a compensatory, neuroplastic response that helps to reduce the severity of depressive symptoms,” said Peterson, director of the Institute of the Developing Mind at CHLA and professor of pediatrics and psychiatry at the Keck School of Medicine of the University of Southern California. “Patients off medication have a thickened cortex, and the thicker it is, the fewer the symptoms they have. Treatment with medication then reduces the severity of symptoms, which in turn reduces the need for biological compensation in the brain — so that their cortex becomes thinner, reaching thickness values similar to those in healthy volunteers.”

    The investigators acquired anatomical brain scans at baseline and again at the end of the 10-week study period for 41 patients with chronic depression, while 39 healthy volunteers were scanned once. This study was conducted with adult patients treated at Columbia University, when Peterson and Bansal were faculty members.

    Patients were randomized to receive active medication duloxetine, a selective serotonin and norepinephrine reuptake inhibitor, or placebo. During the trial, patients receiving medication experienced significant improvement of symptoms compared with patients receiving placebo. In medication-treated patients, cortical thickness declined toward values found in healthy volunteers while placebo-treated patients showed a slight thickening of the cortex. According to Bansal, a researcher at CHLA and professor of pediatrics at the Keck School of Medicine of USC, this finding suggests that placebo-treated patients continue to require compensation for their ongoing symptoms.

    “Although this study was conducted in adults, the methodology developed — pairing a randomized controlled trial with MRI scanning — can be applied to many other populations in both children and adults,” said Bansal. “Also, our observations of neuroplasticity suggest new biological targets for treatment of persons with neuropsychiatric disorders.”


  2. Twice weekly yoga classes plus home practice may help reduce symptoms of depression

    March 19, 2017 by Ashley

    From the Boston University Medical Center press release:

    People who suffer from depression should participate in yoga and deep (coherent) breathing classes at least twice weekly plus practice at home to receive a significant reduction in their symptoms.

    The findings, which appear in the Journal of Alternative and Complementary Medicine, provide preliminary support for the use of yoga-based interventions as an alternative or supplement to pharmacologic treatments for depression.

    Major depressive disorder (MDD) is common, recurrent, chronic and disabling. Due in part to its prevalence, depression is globally responsible for more years lost to disability than any other disease. Up to 40 percent of individuals treated with antidepressant medications for MDD do not achieve full remission. This study used lyengar yoga that has an emphasis on detail, precision and alignment in the performance of posture and breath control.

    Individuals with MDD were randomized to the high dose group, three 90-minute classes a week along with home practice, or the low dose group, two 90-minute classes a week, plus home practice. Both groups had significant decreases in their depressive symptoms and no significant differences in compliance. Although a greater number of subjects in the high dose group had less depressive symptoms, the researchers believe attending twice weekly classes (plus home practice) may constitute a less burdensome but still effective way to gain the mood benefits from the intervention.

    “This study supports the use of a yoga and coherent breathing intervention in major depressive disorder in people who are not on antidepressants and in those who have been on a stable dose of antidepressants and have not achieved a resolution of their symptoms,” explained corresponding author Chris Streeter, MD, associate professor of psychiatry and neurology at Boston University School of Medicine and a psychiatrist at Boston Medical Center.

    According to Streeter compared with mood altering medications, this intervention has the advantages of avoiding additional drug side effects and drug interactions. “While most pharmacologic treatment for depression target monoamine systems, such as serotonin, dopamine and norepinephrine, this intervention targets the parasympathetic and gamma aminobutyric acid system and provides a new avenue for treatment.”


  3. Study suggests depression symptoms due to chronic sinus disease interfere with productivity

    March 14, 2017 by Ashley

    From the Massachusetts Eye and Ear Infirmary media release:

    Depressed patients with chronic rhinosinusitis (CRS) are more likely to miss days of work or school than those without depression symptoms, according to the results of a new study led by the Sinus Center at Massachusetts Eye and Ear. The findings, published online in Annals of Allergy, Asthma and Immunology, identify depression symptoms as the primary driver of lost days of productivity in patients with CRS, paving the way for more individualized therapy to improve overall quality of life in these patients.

    “In this study, we found that of all symptoms related to CRS — sinus, nasal or otherwise — the severity of depressed mood and depression symptomatology was the predominant factor associated with how often our CRS patients missed work or school due to their CRS,” said senior author Ahmad R. Sedaghat, M.D., Ph.D., a sinus surgeon at Mass. Eye and Ear and assistant professor of otolaryngology at Harvard Medical School. “The severity of even symptoms most typically related to CRS, such as nasal congestion, was not associated with how often our patients missed work or school due to their CRS.”

    One of the more prevalent chronic illnesses in the United States, CRS has been known to cause significant quality of life detriments to affected patients, who often cannot breathe or sleep easily due to obstructed nasal and sinus passages.

    The researchers previously identified four categories of symptoms that dominate CRS — disturbances of sleep, nasal obstruction, ear and facial pain and emotional function. In subsequent studies, they showed that disturbed sleep and ear/facial pain are most associated with overall poorer quality of life.

    In search of an association with lost productivity, the researchers assessed these four categories of symptoms in 107 patients with CRS using a standardized survey. On average, study participants reported three missed days of work or school in a three-month period, or 12 missed days in a year. When the researchers took a closer look at the surveys, they identified emotional symptoms, in which depression symptoms are the strongest feature, as the primary driver of missed days of work or school.

    The researchers were surprised to find that there was not an association between sleep disturbance or nasal obstruction symptoms — symptoms which are more commonly thought of in relation to CRS — with CRS patients missing days of work or school.

    “These findings really point to the fact that specific elements (in this case, symptoms) of CRS may be driving specific disease manifestations or consequences of the disease” Dr. Sedaghat said. In an effort to specifically tailor our CRS treatment to each patient, we have to be cognizant not just of the overall severity of the disease, but also of the severity of individual aspects, symptoms and manifestations of the disease. In this case, we have found that depressed mood, which CRS patients commonly experience, is associated with a particular consequence of the disease — that patients may miss work because of CRS — and these results open the door to exploring interventions directed at depressed mood for reducing productivity losses due to CRS.”


  4. Pinpointing the mechanisms that underlie emotional responses to pain

    by Ashley

    From the JCI media release:

    Pain serves as a warning signal to indicate the intensity and location of damage to the body. In addition to unpleasant sensations, painful events trigger negative emotional responses that may serve to reinforce pain-avoiding behaviors. However, in chronic inflammatory conditions, negative emotional states associated with long-term pain can put affected individuals at a higher risk for psychiatric complications such as depression or substance abuse.

    Signaling by molecules called prostaglandins plays a key role in the body’s response to inflammation. Prostaglandins been linked to the sensory perception of pain, but their role in the emotional response to pain is unclear. This week in the JCI, a study conducted by David Engblom’s lab at Linköping University in Sweden has demonstrated that the aversive effects of inflammatory pain are driven by prostaglandin signaling specifically on serotonin-producing neurons in the brainstem.

    When the researchers selectively blocked prostaglandin synthesis in neurons, mice displayed reduced aversive responses to inflammation-induced pain. Furthermore, mice lacking prostaglandin receptors on serotonin-producing neurons and mice lacking the serotonin transporter also exhibited less pain-avoidance behavior. Prostaglandin signaling in serotonin neurons was not required for aversive responses to high temperatures, suggesting that this pain-aversive signaling pathway is specific to inflammatory pain. These findings suggest that the effects of prostaglandin on serotonin signaling are key drivers of the emotional response to pain, implicating a pathway that may be targeted in future therapeutics for managing pain in chronic inflammatory conditions.


  5. Study suggests learning to reduce rumination may help in coping with depression

    by Ashley

    From the Norwegian University of Science and Technology media release:

    Depressed individuals “don’t need to worry and ruminate,” says Professor Roger Hagen, at the Norwegian University of Science and Technology’s (NTNU) Department of Psychology. “Just realizing this is liberating for a lot of people.”

    Hagen and NTNU colleagues Odin Hjemdal, Stian Solem, Leif Edward Ottesen Kennair and Hans M. Nordahl have ecently published a scientific paper on the treatment of depression using metacognitive therapy (MCT).

    The study shows that learning to reduce rumination is very helpful for patients with depressive symptoms.

    Some people experience their persistent ruminative thinking as completely uncontrollable, but individuals with depression can gain control over it,” says Hagen.

    The patients involved in the study were treated over a ten-week period. After six months, 80 per cent of the participants had achieved full recovery from their depression diagnosis.

    “The follow-up after six months showed the same tendency,” says Hagen.

    Separating thoughts and reality

    Today, medications and cognitive-behavioural therapy (CBT) are the recommended treatments for depression and anxiety. In CBT, patients engage in analysing the content of their thoughts to challenge their validity and reality test them.

    Metacognitive therapy, by contrast, focuses on lessening the ruminative process.

    “Anxiety and depression give rise to difficult and painful negative thoughts. Many patients have thoughts of mistakes, past failures or other negative thoughts. Metacognitive therapy addresses thinking processes,” Hagen says, rather than the thought content.

    Patients with depression “think too much, which MCT refers to as ‘depressive rumination.’ Rather than ruminating so much on negative thoughts, MCT helps patients to reduce negative thought processes and get them under control,” he says.

    By becoming aware of what happens when they start to ruminate, patients learn to take control of their own thoughts.

    As Hagen explains, “Instead of reacting by repeatedly ruminating and thinking ‘how do I feel now?’ you can try to encounter your thoughts with what we call ‘detached mindfulness.’ You can see your thoughts as just thoughts, and not as a reflection of reality. Most people think that when they think a thought, it must be true. For example, if I think that I’m stupid, this means I must be stupid. People strongly believe that their thoughts reflect reality.”

    Fewer relapses

    Patients who participated in the study have been pleasantly surprised by this form of treatment.

    “The patients come in thinking they’re going to talk about all the problems they have and get to the bottom of it,” says Hagen, “but instead we try to find out how their mind and thinking processes work. You can’t control what you think, but you can control how you respond to what you think.”

    The problem with several previous depression studies is that many of them did not use any control groups. Since depression often resolves itself over time, the lack of a control group makes it difficult to know whether a treatment was successful, or if the depression just naturally resolved itself.

    NTNU’s study compared the MCT group against one that did not receive treatment, which strengthened the results of their study.

    According to Hagen, a lot of mainstream depression treatment shows a high recurrence rate. Out of 100 patients, fully half relapse after a year, and after two years, 75 of the 100 have relapsed.

    “The relapse rate in our study is much lower. Only a few per cent experienced a depressive relapse,” he says.

    Could become the standard treatment

    The University of Manchester in England has developed the metacognitive therapy approach over the past 20 years, as a form of cognitive therapy. Smaller studies at this university have shown that MCT treatment has had great efficacy in treating depression. A similar, soon-to-be-published study in Denmark has shown the same positive results.

    Hagen hopes that metacognitive therapy will become the most common way to treat depression in Norway.

    “When the national guidelines for the treatment of depression were changed five or six years ago,” Hagen says, “MCT had not been empirically tested.” Given the results of the NTNU and Danish studies, he recommends that professionals in the field consider whether this form of therapy should become the first choice for treating depression in people suffering from this mental disorder. “Many professionals in Norway have expertise in metacognitive therapy,” says Hagen.

    Journal Reference:

    1. Roger Hagen, Odin Hjemdal, Stian Solem, Leif Edward Ottesen Kennair, Hans M. Nordahl, Peter Fisher, Adrian Wells. Metacognitive Therapy for Depression in Adults: A Waiting List Randomized Controlled Trial with Six Months Follow-Up. Frontiers in Psychology, 2017; 8 DOI: 10.3389/fpsyg.2017.00031

  6. Depression as hard on the heart as obesity and cholesterol

    January 23, 2017 by Ashley

    From the Helmholtz Zentrum München – German Research Center for Environmental Health media release:

    Depression poses a risk for cardiovascular diseases in men that is just as great as that posed by high cholesterol levels and obesity. This is according to a report recently published in the Atherosclerosis journal by researchers from the Helmholtz Zentrum München, together with colleagues from the Technical University of Munich (TUM) and the German Center for Cardiovascular Disease (DZHK).

    According to the World Health Organisation WHO, 350 million people worldwide are affected by depression. But the mental state is not all that is affected, however, and depression can also compromise the body. “Meanwhile there is little doubt that depression is a risk factor for cardiovascular diseases,” explains Karl-Heinz Ladwig. He is group leader at the Institute of Epidemiology II at the Helmholtz Zentrum München, professor of psychosomatic medicine at TUM’s Klinikum rechts der Isar as well as scientist of DZHK. “The question now is: What is the relationship between depression and other risk factors like tobacco smoke, high cholesterol levels, obesity or hypertension — how big a role does each factor play?”

    In order to examine this question, Ladwig and his team analyzed data from 3,428 male patients between the ages of 45 and 74 years and observed their development over a period of ten years. “The work is based on a prospective population-based data set from the MONICA/KORA study that, with a total term of up to 25 years, is one of the few large studies in Europe that allows such an analysis,” reports the statistician Dr. Jens Baumert of Helmholtz Zentrum München, who was also involved in the publication.

    Investigate depression in high-risk patients

    In their analyses, the scientists compared the impact of depression with the four major risk factors. “Our investigation shows that the risk of a fatal cardiovascular disease due to depression is almost as great as that due to elevated cholesterol levels or obesity,” Ladwig summarizes. The results show that only high blood pressure and smoking are associated with a greater risk. Viewed across the population, depression accounts for roughly 15 percent of the cardiovascular deaths. “That is comparable to the other risk factors, such as hypercholesterolemia, obesity and smoking,” Ladwig states. These factors cause 8.4 to 21.4 percent of the cardiovascular deaths.

    “We invested a great deal of time in this work, just due to the long observation period,” says study leader Ladwig. But the effort paid off: “Our data show that depression has a medium effect size within the range of major, non-congenital risk factors for cardiovascular diseases.” Ladwig accordingly proposes consequences here: “In high risk patients, the diagnostic investigation of co-morbid depression should be standard. This could be registered with simple means.”

     


  7. Maternal depression across the first years of life impacts neural basis of empathy in children

    January 9, 2017 by Ashley

    From the Elsevier media release:

    pregnancy coupleExposure to early and chronic maternal depression markedly increases a child’s susceptibility to psychopathology and social-emotional problems, including social withdrawal, poor emotion regulation, and reduced empathy to others.

    Since 15-18% of women in industrial societies and up to 30% in developing countries suffer from maternal depression, it is of clinical and public health concern to understand the effects of maternal depression on children’s development. A study published in the January 2017 issue of the Journal of the American Academy of Child and Adolescent Psychiatry (JAACAP) followed children of mothers with depression from birth to preadolescence and tested depression’s impact on children’s neural empathic response to others’ distress.

    While previous studies have demonstrated the effects of maternal depression on children’s limited response to other’s pain, this new study is the first to examine this topic in a longitudinal sample of mother-child pairs followed from birth to age 11. This carefully selected sample of women with no comorbid contextual risk, who were repeatedly assessed for maternal depression across the first years of life, was utilized in order to compare children of mothers who were chronically depressed and children who were never exposed to any maternal psychopathology. 27 children of mothers with depression took part in the study, as well as 45 controls. They were home-visited at 9 months and 6 years to examine mother-child interaction patterns and were invited to a magnetoencephalography (MEG) session at age 11 in order to evaluate their neural reaction to pain in others.

    We were amazed to see that maternal depression in and of itself was related to differential neural processing of others’ pain in 11-year-old children. We found that the neural reaction to pain in children of depressed mothers stops earlier than in controls, in an area related to socio-cognitive processing, so that children of depressed mothers seem to reduce mentalizing-related processing of others’ pain, perhaps because of difficulty in regulating the high arousal associated with observing distress in others,” said Prof. Ruth Feldman, director of the Developmental Social Neuroscience Lab and the Irving B. Harris Early Childhood Community Clinic at Bar-Ilan University and lead author of the study.

    The researchers also found that mother-child interaction patterns had a crucial role on this effect. When mother-child interactions were more synchronous, that is, mother and child were better attuned to one another, and when mothers were less intrusive, children showed higher mentalizing-related processing in this crucial brain area.

    “It is encouraging to see the role of mother-child interactions in our findings. Depressed mothers are repeatedly found to show less synchronous and more intrusive interactions with their children, and so it might explain some of the differences found between children of depressed mothers and their peer controls in our study,” added Prof. Feldman. “If so, our findings highlight a point of entry, where future interventions can focus their attention to help reduce the effects of maternal depression on children’s psychosocial development.”

    Asked what next steps should be taken, Feldman responded: “The main clinical question now becomes: what strategies are most effective to improve mother-child interaction patterns for depressed mothers and their offspring. Moreover, if we are able to help these mothers be more attuned and less intrusive, will it be enough in order to enable resilience in the offspring? In addition, there are further scientific questions about the manner in which patterns of maternal care implement in the development of children’s brain, endocrine systems, behavior, and relationships.”

    To that end, Feldman and her team are studying how maternal depression and mother-child interactions are associated with children’s stress hormones, behavioral empathy, hormones related to bond formation, and their neural reaction to affiliative cues. Feldman is planning to study intervention strategies that focus on the mother-child interaction pattern, and is hopeful that if successful, these strategies will improve mental health and social adjustment in children of mothers with depression. “Wouldn’t it be interesting and promising if an intervention focused on synchronous mother-child interactions could also reduce the prevalence of psychopathology in the children of depressed mothers?” she concluded.

     


  8. Tablet devices show promise in managing agitation among patients with dementia

    by Ashley

    From the McLean Hospital media release:

    senior researcher with tabletA new pilot study led by McLean Hospital’s Ipsit Vahia, MD, medical director of Geriatric Psychiatry Outpatient Services at McLean Hospital, suggests that the use of tablet computers is both a safe and a potentially effective approach to managing agitation among patients with dementia.

    “Tablet use as a nonpharmacologic intervention for agitation in older adults, including those with severe dementia, appears to be feasible, safe, and of potential utility,” said Vahia. “Our preliminary results are a first step in developing much-needed empirical data for clinicians and caregivers on how to use technology such as tablets as tools to enhance care and also for app developers working to serve the technologic needs of this population.”

    “Use of Tablet Devices in the Management of Agitation Among Inpatients with Dementia: An Open Label Study” was recently published in the online version of The American Journal of Geriatric Psychiatry. This research builds upon previous studies demonstrating that art, music, and other similar therapies can effectively reduce symptoms of dementia without medication. By using tablet devices to employ these therapies, however, patients and providers also benefit from a computer’s inherent flexibility.

    “The biggest advantage is versatility,” said Vahia. “We know that art therapy can work, music therapy can work. The tablet, however, gives you the option of switching from one app to another easily, modifying the therapy seamlessly to suit the individual. You don’t need to invest in new equipment or infrastructure.”

    Researchers loaded a menu of 70 apps onto the tablets for the study. The apps were freely available on iTunes and varied greatly in their cognitive complexity — from an app that displayed puppy photos to one that featured Sudoku puzzles.

    The researchers found that tablet use was safe for every patient, regardless of the severity of their dementia, and that with proper supervision and training, the engagement rate with the devices was nearly 100 percent. The study also found that the tablets demonstrated significant effectiveness in reducing symptoms of agitation, particularly — but not exclusively — among patients with milder forms of dementia.

    Vahia cited several examples of the tablet’s potential to improve a patient’s condition. One particular patient, who only spoke Romanian, was very withdrawn and irritable, and medications were ineffective in controlling his symptoms.

    “We started showing him Romanian video clips on YouTube, and his behavior changed dramatically and instantaneously,” said Vahia. “His mood improved. He became more interactive. He and his medical support team also started using a translation app so that staff could ask him simple questions in Romanian, facilitating increased interaction. These significant improvements are a clear testament of the tablet’s potential as a clinical tool.”

    Based on such promising outcomes, the Geriatric Psychiatry Outpatient Services clinical team is expanding the use of tablet devices as a means to control agitation in dementia patients at McLean. This will allow researchers to develop more robust data and expand the scope of the study, including a focus on specific clinical factors that may impact how patients with dementia engage with and respond to apps.


  9. Gaming your brain to treat depression

    January 6, 2017 by Ashley

    From the University of Washington Health Sciences/UW Medicine media release:

    Researchers have found promising results for treating depression with a video game interface that targets underlying cognitive issues associated with depression rather than just managing the symptoms.

    “We found that moderately depressed people do better with apps like this because they address or treat correlates of depression,” said Patricia Areán, a UW Medicine researcher in psychiatry and behavioral sciences.

    The first study enrolled older adults diagnosed with late-life depression into a treatment trial where they were randomized to receive either a mobile, tablet-based treatment technology developed by Akili Interactive Labs called Project: EVO or an in-person therapy technique known as problem-solving therapy (PST).

    Project: EVO runs on phones and tablets and is designed to improve focus and attention at a basic neurological level. The results, published Jan. 3 in the journal Depression and Anxiety, showed that the group using Project: EVO demonstrated specific cognitive benefits (such as attention) compared to the behavioral therapy, and saw similar improvements in mood and self-reported function. Joaquin A. Anguera, a University of California, San Francisco (UCSF), researcher in neurology and psychiatry, is the lead author, and Areán is the senior author. The researchers have no commercial interests in the intervention manufactured by Akili Interactive Labs in Boston.

    “While EVO was not directly designed to treat depressive symptoms; we hypothesized that there may indeed be beneficial effects on these symptoms by improving cognitive issues with targeted treatment, and so far, the results are promising,” said Anguera.

    People with late-life depression (60+) are known to have trouble focusing their attention on personal goals and report trouble concentrating because they are so distracted by their worries. Akili’s technology was designed to help people better focus their attention and to prevent people from being easily distracted.

    Areán, a UW Medicine researcher in psychiatry and behavioral sciences, said most of the participants had never used a tablet, let alone played a video game, but compliance was more than 100 percent. The participants were required to play the game five times a week for 20 minutes, but many played it more. Participants in this arm of the study also attended weekly meetings with a clinician. The meetings served as a control for the fact that participants in the problem-solving therapy arm were seen in person on a weekly basis, and social contact of this nature can have a positive effect on mood.

    Second study

    A second study, which was another joint effort by UW and UCSF, randomized more than 600 people across the United States assessed as moderately or mildly depressed to one of three interventions: Akili’s Project: EVO; iPST, an app deployment of problem-solving therapy; or a placebo control (an app called Health Tips, which offered healthy suggestions).

    Areán, the lead researcher on the study published Dec. 20 in the Journal of Medical Internet Research (JIMR), found that people who were mildly depressed were able to see improvements in all three groups, including the placebo. However, those individuals who were more than mildly depressed showed a greater improvement of their symptoms following their use of Project EVO or iPST versus the placebo.

    Areán said much of her research is aimed at providing effective treatment to people who need it, and these results provide great potential for helping people who don’t have the resources to access effective problem solving therapy. But, she stressed, the apps should be used under clinical supervision because without a human interface, people were not as motivated to use it. In the JIMR study, 58 percent of participants did not download the app.

    Akili’s technologies are based on a proprietary neuroscience approach developed to target specific neurological systems through sensory and digital mechanics. The company’s technology platform used in this trial is based on cognitive science exclusively licensed from the lab of Dr. Adam Gazzaley at UCSF, and propietary adaptive algorithms developed at Akili, which are built into action video game interfaces. The technology targets an individual’s core neurological ability to process multiple streams of information.

    Project: EVO is undergoing multiple clinical trials for use in cognitive disorders — including Alzheimer’s disease, traumatic brain injury and pediatric attention deficit hyperactivity disorder (ADHD), and the company is on path for potential FDA clearance for the game’s use to treat pediatric ADHD.


  10. Lack of joy from music linked to brain disconnection

    January 5, 2017 by Ashley

    From the McGill University media release:

    Brain MusicHave you ever met someone who just wasn’t into music? They may have a condition called specific musical anhedonia, which affects three-to-five per cent of the population.

    Researchers at the University of Barcelona and the Montreal Neurological Institute and Hospital of McGill University have discovered that people with this condition showed reduced functional connectivity between cortical regions responsible for processing sound and subcortical regions related to reward.

    To understand the origins of specific musical anhedonia, researchers recruited 45 healthy participants who completed a questionnaire measuring their level of sensitivity to music and divided them into three groups of sensitivity based on their responses. The test subjects then listened to music excerpts inside an fMRI machine while providing pleasure ratings in real-time. To control for their brain response to other reward types, participants also played a monetary gambling task in which they could win or lose real money.

    Using the fMRI data, the researchers found that while listening to music, specific musical anhedonics presented a reduction in the activity of the Nucleus Accumbens, a key subcortical structure of the reward network. The reduction was not related to a general improper functioning of the Nucleus Accumbens itself, since this region was activated when they won money in the gambling task.

    Specific musical anhedonics, however, did show reduced functional connectivity between cortical regions associated with auditory processing and the Nucleus Accumbens. In contrast, individuals with high sensitivity to music showed enhanced connectivity.

    The fact that subjects could be insensible to music while still responsive to another stimulus like money suggests different pathways to reward for different stimuli. This finding may pave the way for the detailed study of the neural substrates underlying other domain-specific anhedonias and, from an evolutionary perspective, help us to understand how music acquired reward value.

    Lack of brain connectivity has been shown to be responsible for other deficits in cognitive ability. Studies of children with autism spectrum disorder, for example, have shown that their inability to experience the human voice as pleasurable may be explained by a reduced coupling between the bilateral posterior superior temporal sulcus and distributed nodes of the reward system, including the Nucleus Accumbens. This latest research reinforces the importance of neural connectivity in the reward response of human beings.

    “These findings not only help us to understand individual variability in the way the reward system functions, but also can be applied to the development of therapies for treatment of reward-related disorders, including apathy, depression, and addiction,” says Robert Zatorre, an MNI neuroscientist and one of the paper’s co-authors.