Ping-Pong bot puts brains on alert
Ping-Pong players’ brains react differently when facing a human versus a machine opponent, suggests research in eNeuro. To capture noise-free brain activity of the parieto-occipital cortices during strenuous activity, researchers developed an electroencephalogram (EEG) cap with a high density of electrodes—240 rather than the traditional 16, 32, or 64—half of which were tasked with measuring noise in the data in order to subtract it from the actual brain signal, a bit like noise-canceling headphones. With the cap in place, 37 players of varying skill levels in the United States faced off against either a robot or a human serving the ball. Regardless of the opponent, the brain activity of participants right before receiving a serve surged in a region that governs planning and integrating movement and vision. When facing a human challenger in Ping-Pong, those neurons typically fired together, indicating a brain in a restful, idle state. But against a robot challenger, brain activity was less coordinated, with brain cells firing out of sync, reflecting a state of expectation and alertness. The researchers speculate that the machine’s lack of body language may trigger the different response. DOI: 10.1523/ENEURO.0463-22.2023opens in new window
Jump in elderly drug overdoses
A study in JAMA Psychiatry indicates that fatal drug overdoses in people 65 and older have quadrupled over the past 2 decades. Using CDC data to calculate the annual overdose death rate from 2002 to 2021 for all U.S. adults 65 years or older, researchers found the rate jumped from 3 deaths per 100,000 people in 2002 to 12 per 100,000 in 2021. The highest rates were among Black people (30.9 overdose deaths per 100,000). In 2021, 3,814 (57%) of 6,702 overdoses in those 65 and older involved an opioid, 2,587 (39%) involved a stimulant, and 1,204 (18%) involved both. About 13% (882) of those overdoses were intentional, 83% (5,541) were unintentional, and 4% (274) were undetermined. Most unintentional overdoses (74%) involved illicitly manufactured drugs such as synthetic opioids, heroin, cocaine, and methamphetamine. Most intentional overdoses (68%) involved prescription opioids, antidepressants, benzodiazepines, antiepileptics, and sedative-hypnotics. DOI: 10.1001/jamapsychiatry.2022.5159opens in new window
Party over truth
A study in the Journal of Experimental Psychology: General indicates that partisan bias better predicts misinformation susceptibility than truth sensitivity—the ability to discriminate between true and false information. Researchers asked 2,423 participants in the United States to evaluate 60 news headlines that varied in accuracy and political slant. They found participants exhibited higher truth sensitivity when they were asked to judge whether the headlines were true or false compared with when they were asked if they would share the headlines. Additionally, the researchers found that the ability to distinguish between true and false information was a surprisingly small factor in misinformation susceptibility. Participants’ tendency to readily accept information compatible with their personal beliefs and political party affinity was a much more critical factor influencing participants’ misinformation susceptibility. DOI: 10.1037/xge0001381opens in new window
Smart can't beat looks
Women and their parents rate ambition and intelligence as most important in a mate, but they still choose more attractive men when considering long-term mates, suggests research in Evolutionary Behavioral Sciences. Researchers asked 150 young women in the United States and the women’s mothers (or fathers, if mothers could not participate) to rate 16 personality traits when considering a long-term romantic partner for themselves or their daughter. The women and their parents said that a long-term partner’s ambition and intelligence were more important than physical attractiveness. They were then shown photographs of two men—one of whom they rated as more attractive than the other. Both photographs were then alternately presented along with two descriptions: one in which the man they rated as more attractive was described as ambitious and intelligent and another representing the same man as disorganized and physically fit. The daughters (68.7%) and their parents (63.3%) both chose the more attractive man as the best long-term dating partner, regardless of his ascribed traits. DOI: 10.1037/ebs0000325opens in new window
Nightmare frequency varies by personality
People with increased openness to experience tend to have nightmares more frequently, suggests a study in Dreaming. Researchers surveyed 224 undergraduate students in Norway about nightmare distress, nightmare frequency, Big Five personality traits, and coping strategies. They found that participants with more pronounced neuroticism (often experiencing negative emotions and easily upset) and those with more pronounced conscientiousness (organized, responsible, and goal-oriented) reported being more distressed by nightmares but not having nightmares more often. People with heightened openness to experience (intellectually curious and novelty-seeking) reported having nightmares more often. In addition, participants with more pronounced extraversion (outgoing and sociable) and those with more pronounced agreeableness (compassionate, cooperative, and trusting) reported having nightmares less often. DOI: 10.1037/drm0000235opens in new window
Anxiety blood test
Research in Molecular Psychiatry describes a blood test that could identify biomarkers that indicate people’s risk for developing anxiety, the severity of their current anxiety, and factors that may suggest which therapies could best treat their anxiety. Researchers looked for mRNA biomarkers in the blood of 58 individuals with psychiatric disorders in the United States to discover changes in gene expression between self-reported low-anxiety and high-anxiety states. They then prioritized the list of candidate biomarkers based on other evidence in the field. Next, they validated the top biomarkers from the discovery and prioritization phases in an independent cohort of 40 psychiatric subjects with clinically severe anxiety. The researchers then tested candidate biomarkers for their ability to predict anxiety severity and anxiety-driven hospitalizations in another independent cohort of 195 psychiatric subjects. They demonstrated increased accuracy of individual biomarkers with a personalized approach by gender and diagnosis, particularly in women. Finally, they identified which biomarkers were targets of existing drugs, including omega-3 fatty acids, fluoxetine, lithium, benzodiazepines, and ketamine. DOI: 10.1038/s41380-023-01998-0opens in new window
Habit circuits linked to eating disorders
Brain regions associated with habit formation are unusually active in people with some eating disorders, according to a study in Science Translational Medicine. Researchers analyzed fMRI brain scans of 178 female participants in the United States to identify regions analogous to areas active in lab rats performing habitual behaviors. This analysis pointed to two structures: the sensorimotor putamen and the associative caudate. The researchers then examined the brains of 34 of the women with binge-eating disorder or bulimia. They found that connectivity of the sensorimotor putamen was altered in participants with binge-eating disorder or bulimia compared with healthy controls, and that the extent to which connections were altered correlated with the severity of participants’ disorders. Specifically, connectivity to the anterior cingulate cortex was decreased, but it was increased to the orbitofrontal cortex and motor cortex. Furthermore, the putamen of the participants with binge-eating disorder or bulimia also had fewer receptors for dopamine, a neurotransmitter released in response to reward, which could explain why eating disorders are resistant to medication. DOI: 10.1126/scitranslmed.abo4919opens in new window
Did AI write this?
According to research in the Proceedings of the National Academy of Sciences, people are able to tell articicial intelligence (AI) authorship only about half the time. Researchers trained multiple AI language models to generate text in three social contexts where trust in the sender is essential: professional (job application), romantic (online dating), and hospitality (Airbnb host description). In three initial experiments, using two different language models, 4,000 participants in the United States identified the source of a written passage with only 50% to 52% accuracy. The researchers found that the agreement between participants’ answers was significantly higher than chance, meaning many participants were coming to the same flawed conclusions about the source of the passages. Three additional experiments with 600 participants revealed that they erroneously assumed that mentions of personal experiences and the use of first-person pronouns indicated a human author. They also mistook rambling, nonsense text as coming from an AI author. DOI: 10.1073/pnas.2208839120opens in new window
Gut bugs and ADHD
Gut microbiome composition may affect a child’s susceptibility to attention-deficit/hyperactivity disorder (ADHD), according to a study in the Journal of Child Psychology and Psychiatry. Researchers in Taiwan compared fecal samples from 35 children with ADHD and 35 healthy controls. They found that samples from children with ADHD had higher levels of certain species of fungi and lower levels of other species. In experiments with cells grown in the lab, researchers discovered that one species found in high quantities in samples from children with ADHD—called Candida albicans—increased the permeability of cells that line the intestine. The researchers hypothesized that this increased intestinal permeability could create a “leaky gut” that allows bacteria into the bloodstream, possibly leading to inflammation throughout the body and brain. DOI: 10.1111/jcpp.13779opens in new window
Mild autism outpaces profound autism
A study in Public Health Reports indicates that about a quarter of autism diagnoses in the United States fall into the recently defined category of profound autism—having an IQ of 50 or less, and/or inability to communicate through speaking. Researchers analyzed school and medical records from 2000 to 2016 for more than 20,000 8-year-olds identified as having autism spectrum disorders. They found that the rate of profound diagnoses grew from about 3 cases per 1,000 children in 2000 to about 5 cases per 1,000 in 2016. However, the rate of children diagnosed with milder autism grew from 4 cases per 1,000 children to 14 cases per 1,000 children over that same time period. Profound autism was more common in girls than boys. There was also a large racial and ethnic gap: Among Black and Hispanic children with autism, 37% and 33% had profound autism, respectively, compared with about 20% of White children with autism. DOI: 10.1177/00333549231163551opens in new window
Bank together, stay together
According to a study in the Journal of Consumer Research, married couples who merge their finances may have happier relationships. Researchers recruited 230 engaged or newlywed couples in the United States and followed them for 2 years. This was the first engagement or marriage for all participants, and all couples began the study with separate accounts. The researchers then randomly assigned some couples to open joint bank accounts or maintain separate accounts instead. Two years later, couples who combined accounts reported higher relationship quality than those who maintained separate accounts. The researchers pinned this phenomenon on merged accounts encouraging better alignment of financial goals, increased transparency, and a deeper sense of unity within a marriage. DOI: 10.1093/jcr/ucad020opens in new window
Suicide in society's most vulnerable
The most socially vulnerable people in the United States are at a much higher risk of suicide than the least vulnerable, according to a study in JAMA Network Open. Researchers analyzed U.S. Centers for Disease Control and Prevention–reported county-level suicides from 2016 to 2020. They compared these rates against county-level social vulnerability measures—the Social Vulnerability Index (SVI) and the Social Vulnerability Metric (SVM). They found that counties in the top 10% most socially vulnerable group saw a 56% (SVI) or 82% (SVM) increase in suicide rate compared with counties in the bottom 10% most socially vulnerable group. The researchers conclude that efforts to reduce social vulnerability may lead to a lifesaving reduction in the rate of suicide. DOI: 10.1001/jamanetworkopen.2023.9995opens in new window
Melatonin linked to less self-harm
A study in the Journal of Child Psychology and Psychiatry indicates that among adolescent girls with depression and anxiety, the use of melatonin was linked with a reduced risk for self-harm. Researchers identified 25,575 children and teenagers in Sweden ages 6 to 18 who were prescribed melatonin—around 75% took a single dose of the medication daily. Over 87% had at least one psychiatric disorder, mainly attention-deficit/hyperactivity disorder (ADHD), anxiety disorders, depression, or autism spectrum disorder. The researchers estimated the risks of self-harm in the same individual while on or off medication by comparing the risk in the last unmedicated month with the 12 months after melatonin treatment was initiated. The risk of self-harm was higher shortly before melatonin was prescribed and it was cut in half the month following initiation of treatment and stayed below initial levels for 12 months. Risk reduction was particularly evident among adolescent girls with depression and/or anxiety disorders. Similar results were found when excluding users of antidepressants. DOI: 10.1111/jcpp.13785opens in new window
Ghosting friends makes us depressed
According to research in Telematics and Informatics, ghosting friends—terminating communication without explanation—increases feelings of depression. Researchers surveyed 978 participants ages 16 to 21 in Germany about how often they engaged in behaviors consistent with ghosting others in romantic relationships and how often they ghosted others in friendships. The participants also answered questions about communication overload on social media, self-esteem, and depressive tendencies. After 4 months, 415 participants completed the survey a second time. The researchers found that communication overload predicted ghosting within romantic relationships but not within friendships. Participants with greater self-esteem were likelier to ghost friends but not romantic partners. The self-esteem of participants who ghosted others was not impacted over time, whether it was a friend or romantic partner the participant ghosted. But participants who reported ghosting friends but not romantic partners in the first survey tended to have more depressive tendencies in the second. Finally, older participants and those with less education were more likely to ghost their romantic partners. Age and education had no impact on ghosting friends. DOI: 10.1016/j.tele.2023.101969opens in new window
Fixing flow of brain signals relieves depression
Depression may be treated by reversing errant brain signals, suggests research in the Proceedings of the National Academy of Sciences. Researchers recruited 33 patients diagnosed with treatment-resistant major depressive disorder in the United States. Twenty-three received a transcranial magnetic stimulation treatment called SNT, and 10 received a sham treatment. When comparing fMRI data in these patients with that of 85 healthy controls without depression, one connection stood out. In the healthy brain, the anterior insula, which regulates bodily sensations, sends signals to the anterior cingulate cortex, which oversees emotions. However, in most participants with depression, that typical flow of activity was reversed. The higher the severity of depression, the higher the proportion of signals that traveled the wrong way. When treated with SNT, the flow of neural activity in depressed patients reverted to the normal direction within a week, coinciding with a lifting of their depression. Those with the most severe depression experienced the greatest symptom relief. DOI: 10.1073/pnas.2218958120opens in new window
Deciphering the stories in our minds
A study in Nature Neuroscience has demonstrated that a large language model, similar to the model underlying ChatGTP, can decode brain scans to approximate the gist of what people are thinking. Researchers asked 3 participants in the United States to lie in an fMRI scanner while listening to several hours of The Moth and other narrative podcasts. The researchers then used a large language model to match patterns in their brain activity to words and phrases the participants heard. They found that almost every word was out of place in the resulting decoded script, but the language model captured the paraphrased meanings of the passages reasonably well. The decoding model also deciphered the gist of stories the fMRI-bound participants first silently imagined telling and then later told out loud. Finally, the model also approximated a brief, silent animated movie participants viewed while in the brain scanner. DOI: 10.1038/s41593-023-01304-9opens in new window
Brain and body health reflect mental health
According to a study in JAMA Psychiatry, poor body health is a better indicator of mental illness than poor brain health. Researchers recruited 173,168 participants in Australia, about half of whom had one or more psychiatric disorders. They first assessed the health of their brain and seven body systems using multimodal brain imaging, blood, urine, and physiological markers. They then quantified the extent to which each organ’s health and function deviated from established normative ranges in participants with schizophrenia, bipolar disorder, depression, and/or generalized anxiety disorder. They found that participants diagnosed with these mental disorders are not only characterized by brain health outside of the normal range; they also present considerably poorer physical health across multiple body systems, particularly of the metabolic, hepatic, and immune systems, compared with their healthy peers. DOI: 10.1001/jamapsychiatry.2023.0791opens in new window
