Background: Marijuana initiation among adults aged 50 years and older has increased substantially. Although acute tetrahydrocannabinol exposure can impair psychomotor function, less is known about how real-world medical marijuana initiation relates to functional tasks such as driving in mid-to-late life. Objective: The objective of our study was to evaluate the feasibility of recruiting and retaining adults aged 50 years and older, who are newly registered for medical marijuana, and matched non–marijuana-using controls, into a longitudinal high-fidelity driving simulator protocol, and to explore preliminary associations between medical marijuana initiation and simulated driving performance. Methods: This prospective, nonrandomized feasibility cohort study enrolled adults aged 50 years and older who are newly registered in the Florida Medical Marijuana Use Registry, along with age-, race-, and sex-matched controls. Assessments occurred at baseline (T1; preinitiation) and at 1 month (T2). Primary feasibility outcomes included recruitment, retention, simulator completion and tolerance, and exposure verification. Exploratory outcomes included reaction time and divided attention (DA) performance, which are measured using an immersive, high-fidelity driving simulator. Results: Recruitment and exposure verification procedures were feasible, but simulator sickness contributed to substantial missing data. Exploratory analyses suggested group differences in select DA outcomes at T2. At T2, reaction time to DA situation 3 (DA3) was significantly shorter in the medical marijuana group (n=14, mean 2.57, SD 1.63) than in the control group (n=7, mean 5.79, SD 4.32; =−2.50, =.02, =−1.11, 95% CI −2.04 to −0.16). These findings should be interpreted cautiously, given the small sample size, missing data, and multiple comparisons. Conclusions: A prospective protocol examining medical marijuana initiation and simulated driving among mid-to-late-life adults is feasible, but future studies should incorporate design and analytic refinements to address simulator sickness and missing data and to better characterize exposure timing and patterns. Trial Registration: ClinicalTrials.gov NCT04629716; https://clinicaltrials.gov/study/NCT04629716
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Two-year longitudinal neuropsychological monitoring after unilateral and staged bilateral subthalamic nucleus deep brain stimulation
IntroductionDeep brain stimulation (DBS) is an increasingly popular therapeutic method for treating motor symptoms in Parkinson’s disease, but its impact on non-motor symptoms in long-term follow-up remains debated.MethodThe primary objective of this study was to monitor the cognitive functioning, mood, and quality of life in 2 years of unilateral and staged bilateral subthalamic nucleus DBS. A cohort of 30 patients was evaluated at three intervals: before DBS surgery, at 6 months, and 24 months post-surgery. The time points of neuropsychological assessments were set to control the impact of unilateral and bilateral DBS throughout the treatment. Two selected groups, unilateral and bilateral DBS, were also analyzed. The study employed a combination of computerized and paper-based tests to assess cognitive functions, alongside questionnaires to gauge emotional state and quality of life. The cognitive evaluation focused on three domains critical for daily activities: attention and processing speed, learning and episodic memory, and executive functions, including working memory and cognitive flexibility.ResultsAnalysis of the entire cohort from baseline through the two follow-up assessments revealed no decline in cognitive function, mood, or quality of life, alongside significant motor improvement. Additional analyses of the two subgroups—unilateral DBS and staged bilateral DBS—also showed no overall decline in any assessed domain over the 2-year follow-up period. However, comparison of cognitive outcomes with normative data indicated a higher proportion of patients meeting criteria for cognitive decline at the 24-month follow-up in the staged bilateral DBS group compared with the unilateral DBS group.ConclusionThe findings support the long-term overall stability of cognitive function, mood, and quality of life following unilateral and staged bilateral subthalamic DBS. Subgroup analyses did not reveal any significant decline in cognitive measures over time. Nevertheless, individual comparisons with normative data showed a higher proportion of patients with memory deficits in the staged bilateral DBS group after the two-year follow-up.
Can exercise combined with transcranial direct current stimulation improve cognitive function in older adults? A systematic review and meta-analysis
ObjectiveThis study investigated whether combining exercise with transcranial direct current stimulation (tDCS) improves overall cognition, memory, and executive function in older adults.MethodsFollowing PRISMA guidelines, we systematically searched databases including PubMed, Web of Science, CNKI, and Wan Fang for randomized controlled trials (RCTs) examining the combined effect of exercise and tDCS on cognitive function in older adults. Used RStudio (version 4.2.0) to merge effect sizes and represent them as SMD with a 95% confidence interval (CI). The main effects are synthesized using a random effects model, and heterogeneity sources are explored through subgroup regression and sensitivity analysis.ResultsThe combined exercise and tDCS intervention significantly improved global cognitive function in older adults (SMD = 0.62, 95% CI: 0.36 to 0.89, p < 0.0001). Significant enhancements were observed in executive function (SMD = 0.54, 95% CI: 0.16 to 0.92, p = 0.005) and general cognitive ability (SMD = 0.75, 95% CI: 0.21 to 1.30, p = 0.006), while memory showed a non-significant improvement (SMD = 0.58, 95% CI: −0.03 to 1.19, p = 0.063). Both interventions lasting less than 6 weeks (SMD = 0.94, 95% CI: 0.60 to 1.27, p < 0.0001) and those lasting 6 weeks or longer (SMD = 0.24, 95% CI: 0.10 to 0.37, p = 0.0006) positively impacted cognitive function. However, the effect size was larger for cognitively healthy older adults (SMD = 0.69, 95% CI: 0.20 to 1.18, p = 0.006) compared to those with cognitive impairment (SMD = 0.60, 95% CI: 0.29 to 0.92, p = 0.0002). The combination of tDCS and integrated exercise produced the largest effect size (SMD = 1.74), despite high heterogeneity, while the combination of tDCS and Tai Chi produced the smallest but most robust effect (SMD = 0.25, I 2 = 0%), indicating that exercise type significantly regulates the intervention effect of tDCS (p = 0.0015). Regression analysis shows that tDCS stimulation time has a significant positive regulatory effect on cognitive function in elderly people (p = 0.0002), while the combined intervention period (p = 0.030) and single exercise time (p = 0.034) both have a significant negative regulatory effect.ConclusionBased on limited evidence, we found that a combined intervention of exercise and tDCS is a potentially effective means of improving cognitive function in older adults. However, the extent of improvement varies with the cognitive domain, baseline performance level, and intervention plan.
A multichannel MEG time–frequency analysis framework for detecting stage -specific effects of spatial distraction in visual-spatial working memory
IntroductionSpatial distraction can disrupt visual-spatial working memory (VSWM), but its stage-dependent effects on multichannel neural dynamics remain insufficiently characterized. This study presents a multichannel magnetoencephalography (MEG) time—frequency analysis framework to detect stage-specific oscillatory responses to spatial distraction during a VSWM task.MethodsMEG signals were recorded from healthy participants under Distractor and No-distractor conditions and analyzed across encoding, maintenance, and retrieval/decision epochs. Time–frequency power was estimated in the delta, theta, alpha, beta, and gamma bands, and condition differences were evaluated using sensor-level spatiotemporal cluster-based permutation testing and Bonferroni correction within each predefined epoch.ResultsThe proposed analysis revealed a clear stage-specific pattern, with the most prominent modulation occurring during maintenance. Specifically, distraction induced robust and sustained increases in theta-, alpha-, and beta-band power during the retention interval (all cluster-level p < 0.01). Theta activity increased rapidly after maintenance onset and remained elevated throughout the full maintenance period over bilateral temporal, and widespread parieto-occipital sensors, while alpha and beta enhancements also showed temporally continuous and spatially stable patterns across widespread sensor networks.DiscussionThese findings highlight sustained large-scale oscillatory modulation as a key neural signature of distraction during mnemonic maintenance. The study provides an interpretable multichannel signal-analysis perspective on distraction effects in working memory and offers a practical framework for stage-resolved analysis of brain dynamics in cognitive tasks.
Virtual reality-based inhibition training influences food-related responses: no additional effects of repetitive transcranial magnetic stimulation
Combining cognitive inhibition training with brain stimulation techniques has received increasing attention as a potential approach to modulating maladaptive food craving and food intake. Building on previous work in this line of research, the current study examined whether virtual reality (VR)-based no-go inhibition training paired with repetitive transcranial magnetic stimulation (rTMS) modulates implicit food-related attitudes, craving and food-choice behaviors. Healthy women with high trait food cravings and a preference for high-calorie foods were assigned to one of four groups in a 2 (rTMS: active vs. sham) × 2 (training: no-go vs. neutral) between-subjects design. High-frequency rTMS was applied over the left dorsolateral prefrontal cortex (DLPFC), and no-go training was implemented in a VR environment using food stimuli tailored to participants’ self-reported preferences. Implicit attitudes and food craving were assessed before and after the intervention, while food choice was measured post-intervention only. Following training, the no-go group showed reduced positive implicit attitudes toward high-calorie foods and increased craving for low-calorie foods compared to pre-training levels, whereas no such changes were observed in the neutral group. Moreover, compared to the neutral group, the no-go group made healthier food choices. No-go training effects on food choice were more pronounced among individuals with low-to-moderate baseline preferences for high-calorie foods. In contrast, no significant main effects or additive effects of rTMS were observed. The present study demonstrates that VR-based no-go training can effectively regulate food-related responses and extends earlier work by demonstrating robust inhibition training effects across implicit and explicit measures, while highlighting the importance of considering individual differences in future research.
Impact of a Prototype Combining Recommender Functionality With Structured Documentation on Operator Performance in Calls to Medical Communication Centers: Quasi-Experimental Feasibility Study
<strong>Background:</strong> Management of contacts to medical communication centers relies heavily on clinical judgment, contextual understanding, and communication skills. Decision support systems, intended to complement medical expertise, may, due to their rigidity, impede effective caller interaction and may, together with the obligatory documentation of calls, contribute to a workflow that draws attention away from the communication. Recommender systems have demonstrated potential in supporting decision-making across various domains by nudging individuals toward better choices without undermining autonomy. We built a prototype that combined artificial intelligence–based question recommendations with structured documentation (hereafter: the prototype) and conducted a feasibility study to test its influence on operators’ performance. <strong>Objective:</strong> This study aimed to examine whether the prototype influenced the operators’ performance during telephone triage. We hypothesized that the prototype would affect medical quality without affecting communication quality. <strong>Methods:</strong> A quasi-experimental pre- and posttest feasibility study was conducted in a simulated setting. Twenty-five operators were voluntarily recruited from 5 Norwegian medical communication centers, in which 22 operators contributed to both the pretest (before the prototype) and the posttest (with the prototype). The operators handled the same 15 medical cases presented by simulated callers, with a 5-month interval between the 2 sessions. The question recommender was trained on other data and then fine-tuned on the 15 scenarios used. Audio recordings of the calls were rated using the tool Assessment of Quality in Telephone Triage. Pre- and posttest values were compared, with overall medical and communication quality as the primary outcomes. Secondary outcomes included specific items related to medical content and communication, accuracy of triage, patient safety, call duration, and efficiency. <strong>Results:</strong> A total of 320 paired calls were analyzed. Overall medical quality improved significantly with use of the prototype, from a mean of 6.83 points pretest to 7.16 points posttest rated on a 10-point scale (difference 0.34, 95% CI 0.11-0.57; <i>P</i>=.004). The effect size was small (Cohen <i>dz</i>=0.16). No significant change was observed in overall communication quality, with a mean of 7.06 points pretest and 6.97 points posttest (difference –0.09 points, 95% CI –0.28 to 0.10; <i>P</i>=.35). A significant decrease from pre‑ to posttest was observed in the specific items “Collects information about the patient’s location” (<i>P</i><.001) and “Ensures that the triage decision is understandable and feasible” (<i>P</i>=.002). None of the remaining secondary outcomes showed significant changes. <strong>Conclusions:</strong> The prototype yielded a modest improvement in medical quality within the scenario‑based test environment. Although overall communication quality remained unchanged, aspects of the interaction were negatively affected. Artificial intelligence–based question recommendations combined with structured documentation may serve as useful functionalities within a decision support system, but each functionality requires further testing and development before such technology can be implemented in the triage of unselected, real‑world calls. <strong>Trial Registration:</strong>
Key takeaways from WHO briefing on hantavirus cruise ship outbreak
The MV Hondius, the cruise ship that has garnered global attention because of an apparent outbreak of person-to-person spread hantavirus infections, is on the move. At the request of Tedros Adhanom Ghebreyesus, the World Health Organization’s director-general, Spain has agreed to let the ship dock off Tenerife, in the Canary Islands. The ship is expected to arrive on Sunday.
This outbreak — the first time hantavirus has been suspected of transmitting on a cruise ship — is an evolving situation. It’s also one that is going to take weeks to resolve, because of the long incubation period of hantaviruses. And it could be months before scientists piece together how the virus got on the boat and whether all the subsequent cases were people infected through contact with other people or whether rodents — which are known to carry hantaviruses — that were on board played any part.
Official leading CDC’s cruise ship program retires
WASHINGTON — The top U.S. official responsible for public health on cruise ships is stepping down, according to an internal Centers for Disease Control and Prevention announcement obtained by STAT.
The retirement of Luis Rodríguez, who has been part of the Vessel Sanitation Program since 2010 and served as its chief since 2023, was announced internally at the CDC on Wednesday.
The Download: the tech reshaping IVF and the rise of balcony solar
This is today’s edition of The Download, our weekday newsletter that provides a daily dose of what’s going on in the world of technology.
What’s next for IVF
IVF has brought millions of babies into the world over the last four decades. But the process can still be slow, painful, and expensive—and far from guaranteed to work. Now, a wave of new technologies aims to change that.
Researchers are using AI to identify promising sperm and embryos, developing robotic systems that could automate parts of the IVF process, and even exploring controversial genetic editing techniques designed to prevent inherited disease.
The technologies could make IVF more effective and accessible. But they’re also raising difficult ethical questions about how far reproductive medicine should go.
—Jessica Hamzelou
This story is from MIT Technology Review’s What’s Next series, which looks across industries, trends, and technologies to give you a first look at the future. You can read the rest of them here.
The balcony solar boom is coming to the US
Dozens of US states are considering legislation to allow people to install plug-in solar systems, often called balcony solar. These small arrays require little to no setup and could help cut emissions and power bills.
Proponents say the systems could make solar power more accessible, but some experts caution that there are safety concerns.
Read the full story on balcony solar’s potentially massive impact in the US.
—Casey Crownhart
This article is from The Spark, our weekly climate newsletter. Sign up to receive it in your inbox every Wednesday.
Resistance: 10 Things That Matter in AI Right Now
Resistance against AI’s proliferation is growing. People from all walks of life are speaking out against rising electricity bills from data centers, disappearing jobs, chatbots’ impact on teen mental health, the military’s use of AI, and copyright infringement—among other concerns.
People want to have a say in how the technology transforms their future. And they’re starting to create small cracks in AI labs’ vision for the future. Find out how.
—Michelle Kim
Resistance is on our list of the 10 Things That Matter in AI Right Now, MIT Technology Review’s guide to what’s really worth your attention in the buzzy world of AI.
The must-reads
I’ve combed the internet to find you today’s most fun/important/scary/fascinating stories about technology.
1 After years of insults, Anthropic and SpaceX have teamed up
Anthropic will tap SpaceX’s GPUs to meet surging demand. (Axios)
+ While SpaceX gets a marquee customer for its AI ambitions. (Wired $)
+ Anthropic says the deal will double Claude Code’s rate limits. (Ars Technica)
+It’s also exploring building compute capacity in space. (CNBC)
+ Musk previously called Anthropic “evil” and “misanthropic.” (Gizmodo)
2 Ex-OpenAI leaders say Sam Altman sowed “chaos” and distrust
Former CTO Mira Murati said she couldn’t trust his words. (The Verge)
+ He also bypassed OpenAI’s safety board before a model release. (Gizmodo)
+ And pitted leaders against one another. (Forbes)
+ But Elon Musk still tried to recruit Altman to lead a Tesla AI lab. (FT $)
+ Here’s why Musk and Altman are in court. (MIT Technology Review)
3 China’s humanoid robots are fueling its next export boom
Morgan Stanley says Beijing has taken an early lead in the sector. (Bloomberg $)
+ Gig workers are training humanoids at home. (MIT Technology Review)
4 SpaceX’s IPO plans will give Elon Musk “virtually unchecked” authority
And erode typical shareholder protections. (Reuters $)
+ Activists and pension funds are pushing back against the IPO. (Wired $)
+ While SpaceX is shifting focus from Falcon 9 to Starship. (Ars Technica)
5 Google DeepMind will use the MMORPG Eve Online for AI model testing
It’s also bought a stake in the game’s maker. (Ars Technica)
+ DeepMind also recently built a new video-game-playing agent. (MIT Technology Review)
6 The US risks isolating its automakers by banning a Chinese EV standard
It’s prohibiting software that’s dominating global EV markets. (Rest of World)
7 Elon Musk’s proposed Texas chip factory could cost $119 billion
It would manufacture chips for Tesla, SpaceX, and xAI. (CNBC)
+ Future AI chips could be built on glass. (MIT Technology Review)
8 Why the “attention-span crisis” is misunderstood
Technology may be exhausting attention rather than shortening it. (Atlantic $)
9 Scientists are getting closer to explaining what causes lightning
New tools are revealing unexpected physics inside thunderstorms. (Quanta)
10 Kids have found an age verification loophole: fake mustaches
Resourceful children are foiling blocks on adult websites. (TechCrunch)
Quote of the day
“My concern was about Sam saying one thing to one person and completely the opposite to another person.”
—Mira Murati, the former CTO of OpenAI, testifies in court that CEO Sam Altman was deceptive, Reuters reports.
One More Thing
ALAMY
A brief, weird history of brainwashing
During the Cold War, the US prepared for a psychic war with the Soviet Union and China by spending millions of dollars on research into manipulating the human brain.
The science never exactly panned out, but residual beliefs fostered by this bizarre conflict continue to play a role in ideological and scientific debates to this day. And now, new technologies are altering how we think about mind control.
This is how the race for mind control changed America forever.
—Annalee Newitz
We can still have nice things
A place for comfort, fun and distraction to brighten up your day. (Got any ideas? Drop me a line.)
+ Listen to the 10 bird songs of spring in this lovely compilation of American species.
+ Good Samaritans saved a 29-foot whale that had wandered too far into a river.
+ Explore the intersection of human emotion and machine learning in this look at AI’s influence on art.
+ Break down the walls between streaming services and manage all your digital music in one place with this app.
Amyloid-β clearance: an astrocytic perspective
Alzheimer’s disease (AD) represents a major global public health challenge in the 21st century, recognized as the neurodegenerative disorder with the highest mortality rate and socioeconomic burden. The core pathological feature of AD is an imbalance in Aβ production and clearance, leading to conformational changes and pathological aggregation of Aβ peptides. This imbalance triggers neurodegenerative cascades 20–30 years before clinical symptoms appear. Therapeutic approaches targeting Aβ production, including β-secretase and γ-secretase inhibitors, have thus far shown limited clinical benefit in late-stage trials and have been further constrained by safety and tolerability concerns. As a result, early interventions aimed at enhancing Aβ clearance have attracted increasing attention. While microglia-mediated phagocytosis of Aβ has been extensively studied, the multifaceted roles of astrocytes in this process remain underexplored. This review synthesizes recent findings to elucidate the molecular mechanisms of astrocyte-mediated Aβ clearance, focusing on endocytic uptake and intracellular degradation, maintenance of the blood–brain barrier, and aquaporin-4 (AQP4)-dependent glymphatic drainage. Additionally, this review dissects key regulatory nodes, including the dynamic modulation of Aβ clearance capacity through astrocyte phenotypic transitions and functional decline associated with pathology. These insights offer a theoretical foundation and translational perspective for the development of astrocyte-targeted interventions in early-stage AD.