Thursday, July 13, 2023

How businesses can cultivate wisdom


Peer-Reviewed Publication

UNIVERSITY OF FLORIDA



We probably all know wise people, mentors and leaders who possess a certain perspective that radiates out and makes us appreciate their presence in our lives. But it can be hard to pinpoint the source of their wisdom. Sometimes it feels like wisdom is one of life’s little secrets, left only for wise people to truly understand.

Fortunately, Monika Ardelt has dedicated herself to revealing these secrets. For decades, Ardelt, a professor of sociology at UF, has studied what makes people wise and how this quality benefits wise individuals and their communities. Her research has established the essential components of wisdom and developed ways to measure the trait.

Ardelt has recently turned her attention to studying wisdom in organizations and businesses to understand how institutions can cultivate wisdom that benefits themselves and their communities. Wise organizations can deepen employee connection to the firm, reducing turnover and improving their work.

So we asked Ardelt about her latest research, which she published recently in the Business and Professional Ethics Journal with her graduate student Bhavna Sharma. They uncovered these elements of organizational wisdom and how businesses can ensure they act wisely.

Q: What is wisdom?

A: Wisdom includes three components: cognitive, reflective and compassionate. This is the three-dimensional wisdom model I developed based on earlier research by neuropsychologist Vivian Clayton.

Wise people don’t necessarily know more than other people, but they understand the deeper meaning of their knowledge and of life in general. They know about themselves, they know who they are. They know about their strengths, but they also know about their weaknesses. They also know how to interact with other people.

This introspection requires the reflective component. Wise people look at events from different angles. This also includes looking at yourself from different angles. In this way, one can judge oneself a little bit more objectively, see one’s own weaknesses. By seeing our own weaknesses, we might become more tolerant of the faults of others.

This tolerance reduces our own ego and therefore makes us more compassionate, which is the third dimension.

Those three dimensions work together and reinforce each other.

Q: What are the benefits of wisdom for individuals?

A: Wise individuals are able to look at things from different perspectives, develop compassion for others and for themselves and have a deeper understanding of life. People are better able to deal with the vicissitudes of life and hardships. Therefore, wise people tend to be more content and satisfied with life.

Q: What makes an organization wise?

A: The ultimate goal of a wise organization is to make the world a better place. That can be done through their products or services. But it’s also about providing a work environment for their employees to make a good living that helps the employees fulfill their potential and flourish.

Q: How do organizations develop wisdom?

A: In our latest study, we uncovered a particular connection to supervisor support. Having a supportive supervisor was linked to organizational wisdom and job fulfillment, which was itself associated with physical and subjective well-being. Wise organizations must develop supportive supervisors to most benefit their employees.

We also developed a new model for studying wise organizations. We merged the three-dimensional wisdom model I developed earlier with self-determination theory, which proposes that people flourish when their basic psychological needs of autonomy, competence, and relatedness are met.

In a wise organization, the cognitive dimension merges with competence. A wise organization serves and benefits all stakeholders. They want to benefit their customers, their employees, the surrounding community, and the environment. 

The reflective element of wisdom is reflected in the autonomy fostered by an organization. Wise organizations don’t treat their employees as pieces of machinery. They treat their employees as human beings and give them enough autonomy to decide how they want to do their work. And wise organizations give their employees enough time for reflection and recuperation so they can achieve a satisfactory work-life balance.

Lastly, the compassionate component of wisdom is tied to the relatedness nurtured in an organization. Organizations bolster relatedness by fostering an ethical and moral culture. This culture creates fairness, appreciation and respect for all employees. Fair pay is one component, because pay inequity does not create a feeling of togetherness but a feeling of separation.

Q: What are the benefits of being a wise organization?

A: You can imagine that an employee who feels fulfilled and energized at their job is more likely to give their all. In this way, wise organizations avoid high turnover or “quiet quitting” and hold on to employees that are committed to the organization.

But this is something we’re still testing. One particular question we have is: Does a wise organization succeed, particularly in the long term? We see some companies, like Purdue Pharma (which was fined heavily for misleading the public about the addictiveness of the opioid OxyContin), that were not acting wisely and have suffered for it. Is the reverse true as well, that wise organizations thrive over time? That’s something we want to answer.

Rising non-native cover in the Santa Monica Mountains threatens native biodiversity and increases fire risk


Analysis shows non-native cover is rising in the Santa Monica Mountains without the influence of fire since 2014, with compounding effects after the 2018 Woolsey Fire

Peer-Reviewed Publication

ARIZONA STATE UNIVERSITY




July 13, 2023 -- The National Park Service has been monitoring plants in hundreds of sites throughout the Santa Monica Mountains National Recreation Area in Southern California since 2014.

new analysis of these data published in the journal Ecosphere shows a steady increase in non-native plant cover since 2014, and rapid regrowth of non-native annual grass and herbaceous species after the 2018 Woolsey Fire, which burned nearly 80% of the entire region.

Furthermore, a region of dense non-native cover was found in the Northern Simi Hills region where biodiversity is significantly low and the native species are at risk of further reduction.

These results indicate that the Santa Monica Mountains are at high risk of losing the native plants that support their unique ecosystem. In addition, the invasive plants that are spreading bring with them an increased risk of damaging wildfires.

Healthy native plant communities are typically resistant to invasion since they are uniquely adapted to Southern California’s dry climate. However, there has been a sharp increase in non-native cover from 4% in 2014 to 29% in 2018, before the Woolsey Fire. Ecosystem stressors such as changing climatic patterns, habitat fragmentation, and alterations in soil chemical properties reduce the resilience of the native plant communities and open the opportunity for invasion.

Nicoletta Stork, the lead author of the study and research analyst in Arizona State University’s Center for Global Discovery and Conservation Science says, “The rise in non-native cover identified in this study is a signal of ecosystem stress from intrinsic and extrinsic factors. The prolonged effects of chronic ecosystem stress are still unknown, but this study has shown a glimpse of the negative repercussions at this moment in time.”

Fire is typically beneficial for native plant communities in this region. However, when invasive seedbanks are prolific in the soil, the reduced shrub cover and newly available resources allow non-natives to germinate and spread. In the Santa Monica Mountains National Recreation Area, invasive non-native annual grasses and annual herbaceous plants regrew to exceed pre-fire cover percentages within a year after the Woolsey fire, reaching 34% in 2020, while native communities underwent natural, albeit slower, regrowth.

The speed at which non-natives regrew after the Woolsey Fire raises concerns as ecosystem stressors continue to affect native resiliency. Amy Mainzer, professor in the Lunar and Planetary Laboratory at the University of Arizona and co-author of the study notes, “This study shows that the weeds are spreading and becoming more prevalent in certain key areas after the fire, pointing to the need to locate and control them because they contribute to the increasing wildfires we are experiencing in the American Southwest.”

The invasive annuals seen growing in the Santa Monica Mountains National Recreation Area accumulate layers of senesced plant material that is easily ignitable, creating a fire hazard that threatens property, the ecosystem, and human lives.

Other negative effects of non-native invasion include reduced biodiversity and altered ecosystems, therefore, locating regions with high non-native cover is crucial to controlling the spread of invasive populations. From this study, a non-native hotspot was located in the Northern Simi Hills region where non-native annual grass species were prominent before the fire. After the fire, certain invasive annual grasses increased, along with invasive mustard and thistle species.

Assessment of the species diversity in this hotspot shows the non-native community is significantly less diverse than native communities. Furthermore, while native communities have notably high shrub cover, non-native communities are comprised of highly flammable annual grasses and herbaceous species.

Robin Martin, associate professor in the School of Ocean Futures at Arizona State University and co-author of the study mentions, “Conversion from one functional group to another is another aspect that can give insight into how ecosystem structure is changing. In this case, the transition from perennial shrublands to annual grasslands could have significant effects on the ecosystem’s hydrologic, carbon, and nutrient cycles, which can lead to more drastic positive feedback loops that eventually extinguish native species.”

Monitoring efforts such as the Park Service’s Inventory and Monitoring program provide insight into the non-native species that are most invasive and the native species that are most at risk of eradication or extinction. While more research must be done to identify the driving factors of invasive spread, studies like this one provide measures of how the ecosystem is changing over time and can point out the locations where management of invasive weeds is most essential.

 

Citation:

Stork, Nicoletta, Amy Mainzer, and Roberta Martin. 2023. “Native and Non-Native Plant Regrowth in the Santa Monica Mountains National Recreation Area after the 2018 Woolsey Fire.” Ecosphere 14(6): e4567. https://doi.org/10.1002/ecs2.4567

A new method allows quantifying the spatial intermittency of ocean currents


The new methodology, developed by an ICM-CSIC team, accurately estimates the horizontal diffusion of water masses in different ocean regions


Peer-Reviewed Publication

SPANISH NATIONAL RESEARCH COUNCIL (CSIC)

The new methodology accurately estimates the horizontal diffusion of water masses in different ocean regions 

IMAGE: THE NEW METHODOLOGY ACCURATELY ESTIMATES THE HORIZONTAL DIFFUSION OF WATER MASSES IN DIFFERENT OCEAN REGIONS view more 

CREDIT: INSTITUTO ESPAÑOL DE OCEANOGRAFÍA



Understanding Atlantic Ocean circulation is key for assessing the global ocean interconnections, in what is known as the "global conveyor belt". This is because the latitudinal ends of the Atlantic, bordering the polar regions, are cold-water formation regions that trigger the onset of the global conveyor belt. Because of their high density, each winter the waters of these polar regions sink and initiate the conveyor belt, thus helping to redistribute heat on a planetary scale, which ultimately influences the climate, especially in Europe.

To quantify this circulation on a planetary scale, it is necessary to understand the intensity of all those processes that cause the spatial and temporal intermittency of the large currents, i.e. the diffusive processes. A new study led by the Institut de Ciències del Mar (ICM-CSIC) in Barcelona, which delves into the processes of horizontal diffusion in the South Atlantic, has developed a new methodology for calculating this diffusion at both regional and global levels.

"The new methodology, which we have named ROD (Radial Offset by Diffusion), allows us to determine the horizontal diffusion coefficients in the ocean and to estimate their spatial variability," states Anna Olivé, leading author of the study.

To carry out this work, published in the prestigious Journal of Atmospheric and Oceanic Technology, researchers analysed the displacements, between 2002 and 2020, of more than 600 drifting buoys, that is, dragged buoys that drift with the ocean currents and hence allow knowing their direction and speed.

"We then numerically simulated these buoys’ trajectories and calculated the distance between the final position of the drifting buoys and that estimated with the numerical simulations, which allowed us to quantify the horizontal diffusive processes existing in the region," adds Anna Olivé.

The study shows that the maximum horizontal diffusion occurs near the ocean surface, in the first 200 m depth, while the minimum values are observed between 1400 and 2000 m depth. Diffusion also increases in the northernmost Antarctic fronts due to the presence of the strong Falkland Current, which flows northwards along the Atlantic coast of Patagonia, reaching La Plata River.

"This important spatial difference confirms the large variability of horizontal diffusion in the ocean, which highlights that a constant coefficient cannot be used throughout the ocean," explains Josep Lluís Pelegrí, co-author of the study.

Unlike others, the ROD method is easy to implement and does not require excessive computational use. According to Anna Olivé, "this facilitates its application and makes it an effective tool for understanding the processes of diffusion and turbulent mixing in regions as dynamic as the Antarctic fronts".

For example, the new methodology will make it possible to know which horizontal diffusion coefficient is most appropriate for studying each oceanic region. Until now, the uncertainties in this parameter has limited the predictive capacity of oceanographic numerical models.

"Thanks to the increase in the number of drifting buoys and the continuous improvements in high-resolution numerical models and reanalysis, the ROD method will provide us with more precise estimates that will allow us to better predict the temporal evolution of large-scale processes that have a major impact on the climate of our planet, such as the global conveyor belt," concludes Anna Olivé.

Despite doubts from quantum physicists: Einstein's theory of relativity reaffirmed


Research teams from Leibniz University Hannover and University of Bremen confirm another equivalence principle


Peer-Reviewed Publication

LEIBNIZ UNIVERSITY HANNOVER

Binary system Earth-Moon 

IMAGE: BINARY SYSTEM EARTH-MOON view more 

CREDIT: AEOS MEDIALAB, ESA 2002



Joint press release by Leibniz University Hannover and ZARM of the University of Bremen

One of the most basic assumptions of fundamental physics is that the different properties of mass – weight, inertia and gravitation – always remain the same in relation to each other. Without this equivalence, Einstein's theory of relativity would be contradicted and our current physics textbooks would have to be rewritten. Although all measurements to date confirm the equivalence principle, quantum theory postulates that there should be a violation. This inconsistency between Einstein's gravitational theory and modern quantum theory is the reason why ever more precise tests of the equivalence principle are particularly important. A team from the Center of Applied Space Technology and Microgravity (ZARM) at University of Bremen, in collaboration with the Institute of Geodesy (IfE) at Leibniz University Hannover, has now succeeded in proving with 100 times greater accuracy that passive gravitational mass and active gravitational mass are always equivalent – regardless of the particular composition of the respective masses. The research was conducted within the framework of the Cluster of Excellence "QuantumFrontiers". Today, the team published their findings as a highlights article in the scientific journal "Physical Review Letters".

 

Physical context
Inertial mass resists acceleration. For example, it causes you to be pushed backwards into your seat when the car starts. Passive gravitational mass reacts on gravity and results in our weight on Earth. Active gravitational mass refers to the force of gravitation exerted by an object, or more precisely, the size of its gravitational field. The equivalence of these properties is fundamental to general relativity. Therefore, both the equivalence of inertial and passive gravitational mass and the equivalence of passive and active gravitational mass are being tested with increasing precision.

What was the study about?
If we assume that passive and active gravitational mass are not equal – that their ratio depends on the material – then objects made of different materials with a different centre of mass would accelerate themselves. Since the Moon consists of an aluminium shell and an iron core, with centres of mass offset against each other, the Moon should accelerate. This hypothetical change in speed could be measured with high precision, via "Lunar Laser Ranging". This involves pointing lasers from Earth at reflectors on the Moon placed there by the Apollo missions and the Soviet Luna programme. Since then, round trip travel times of laser beams are recorded. The research team analysed “Lunar Laser Ranging” data collected over a period of 50 years, from 1970 to 2022, and investigated such mass difference effects. Since no effect was found, this means that the passive and active gravitational masses are equal to approximately 14 decimal places. This estimate is a hundred times more accurate than the best previous study, dating back to 1986.

Unique expertise
LUH's Institute of Geodesy – one of only four centres worldwide analysing laser distance measurements to the Moon – has unique expertise in assessing the data, particularly for testing general relativity. In the current study, the institute analysed the Lunar Laser Ranging measurements, including error analysis and interpretation of the results.

Vishwa Vijay Singh, Jürgen Müller and Liliane Biskupek from the Institute of Geodesy at Leibniz University Hannover, as well as Eva Hackmann and Claus Lämmerzahl from the Center of Applied Space Technology and Microgravity (ZARM) at the University of Bremen published their findings in the journal Physical Review Letters, where the paper was highlighted in the category "editors' suggestion”.

Targeted prevention helps stop homelessness before it starts


A new study from the University of Notre Dame shows that efforts to prevent homelessness work and benefits to homelessness prevention exceed the costs


Peer-Reviewed Publication

UNIVERSITY OF NOTRE DAME

James Sullivan 

IMAGE: HOMELESSNESS HAS BECOME AN INCREASINGLY WORRISOME CRISIS IN OUR NATION OVER THE PAST SEVERAL YEARS, BUT A NEW STUDY FROM THE UNIVERSITY OF NOTRE DAME SHOWS THAT EFFORTS TO PREVENT HOMELESSNESS WORK. RESEARCHERS FROM NOTRE DAME FOUND THAT INDIVIDUALS AND FAMILIES OFFERED EMERGENCY FINANCIAL ASSISTANCE WERE 81 PERCENT LESS LIKELY TO BECOME HOMELESS WITHIN SIX MONTHS AND 73 PERCENT LESS LIKELY WITHIN 12 MONTHS, AS REPORTED IN THEIR STUDY RECENTLY PUBLISHED BY THE REVIEW OF ECONOMICS AND STATISTICS. view more 

CREDIT: UNIVERSITY OF NOTRE DAME



Homelessness has become an increasingly worrisome crisis in our nation over the past several years, but a new study from the University of Notre Dame shows that efforts to prevent homelessness work. 

The issue has reached such proportions in California, for example, that mayors of several major cities have declared a state of emergency on homelessness. In response, leaders in California have invested billions in homelessness programs, including some that target prevention.

Prevention efforts, however, have led to questions — even from organizations committed to addressing homelessness — as to whether such programs are effective, due to the difficulty of targeting assistance to those with the greatest risk of becoming homeless. To test the impact of providing financial assistance to those susceptible to losing their housing, researchers at Notre Dame conducted a randomized controlled trial to evaluate the effect of emergency financial assistance (EFA) on families receiving support through the Santa Clara County Homelessness Prevention System, which is co-led by Destination: Home, a nonprofit organization dedicated to ending homelessness in Silicon Valley.

David Phillips, a research professor in the Wilson Sheehan Lab for Economic Opportunities (LEO) within Notre Dame’s economics department, and James Sullivan, a professor of economics and co-founder of LEO, found that people offered EFA were 81 percent less likely to become homeless within six months of enrollment and 73 percent less likely within 12 months, as reported in their study recently published by The Review of Economics and Statistics.

The study evaluated individuals and families at imminent risk of being evicted or becoming homeless who were allocated EFA between July 2019 and December 2020, with the average household receiving nearly $2,000. Recipients were chosen from among a larger group of people eligible for the program based on their vulnerability to homelessness and on a randomized system set up by LEO and Destination: Home. This temporary financial assistance helped pay rent, utilities or other housing-related expenses on their behalf.

A common approach to fighting homelessness is to provide shelter to those who are already homeless, but the researchers argued that once a family or individual becomes homeless, they face even more difficulties — such as finding permanent housing, basic necessities and health care. They are also more likely to become involved in the criminal justice system and experience frequent hospital visits. LEO’s study found that a preventive approach focusing directly on helping those who are on the brink of homelessness can also be effective.

“Our estimates suggest that the benefits to homelessness prevention exceed the costs,” the researchers said. They estimated that communities get $2.47 back in benefits per net dollar spent on emergency financial assistance.

“Policymakers at all levels are struggling to make really hard decisions about how to allocate scarce resources to address this pervasive problem,” Sullivan said. “But this study shows that you can actually target the intervention to those at risk, which moves the needle on homelessness enough to justify making the investment.”

Phillips added that while homelessness prevention programs are not a panacea to other problems often associated with the most visible forms of homelessness — such as health and substance abuse issues — it is still an effective way to help people.

“Every person who ends up homeless is a little different from the next, and the reasons they’re there are different, but it’s the kind of help they need at the moment they need it, before everything falls apart,” Phillips said.

One of LEO’s main tenets is to take a rigorous approach to fighting poverty by helping service providers apply scientific evaluation methods to better understand and share effective poverty interventions. Said Sullivan, “A big part of LEO’s mission is to create evidence that helps improve the lives of those most vulnerable. Because we have far greater needs than we have resources to address them, we have a real incentive to allocate those resources to the programs that are most effective. This evidence helps shape the decisions of those on the front lines fighting homelessness and poverty.”

Jennifer Loving, chief executive officer of Destination: Home, said the LEO study has implications both locally and nationally. “This could inspire other jurisdictions to stand up their own homelessness prevention systems, using this research as a model or starting point for how to do that on their own — as well as justification to policymakers for funding,” Loving said.

The Santa Clara County Homelessness Prevention System relies on a partnership to help at-risk families and individuals maintain their housing by providing financial assistance as well as case management, legal assistance, financial counseling and landlord dispute resolution. Destination: Home, one of the system’s lead organizations, gathers funding from the federal, county and city governments, as well as private foundations, and coordinates the efforts of a network of 19 nonprofit partners.

Contact: Tracy DeStazio, associate director of media relations, 574-631-9958 or tdestazi@nd.edu

Palaeontology: New ancient Asian alligator species identified


Peer-Reviewed Publication

SCIENTIFIC REPORTS




A new species of ancient alligator from Thailand that is closely related to the Chinese alligator (Alligator sinensis) is described in a study published in Scientific Reports.

Gustavo Darlim, Márton Rabi, Kantapon Suraprasit, Pannipa Tian and colleagues identified the new species by examining a near complete fossilised skull — which they date to younger than 230,000 years old — from Ban Si Liam, Thailand. They have named the species Alligator munensis in reference to the nearby Mun River. The authors examined the remains and investigated the evolutionary relationships between A. munensis and other species by comparing it’s remains with those of 19 specimens from four extinct alligator species, as well as the living American alligator (Alligator mississippiensis), Chinese alligator and spectacled caiman (Caiman crocodilus) species. They also reviewed previously published research on the skeletal characteristics of, and evolutionary relationships between, alligator species.

The authors identified several skull features that are unique to A. munensis, including a broad and short snout, a tall skull, reduced number of tooth sockets and nostrils that are positioned far from the tip of the snout. In addition, they note similarities between the skulls of A. munensis and the Chinese alligator, such as the presence of a small opening in the roof the mouth, a ridge on the top of the skull, and a raised ridge behind the nostrils. They propose that the two species are closely related and may have shared a common ancestor in the lowlands of the Yangtze-Xi and Mekong-Chao Phraya river systems. They speculate that increases in the elevation of the southeastern Tibetan Plateau between 23 and five million years ago may have led to the separation of different populations and evolution of two separate species.

The authors observed that A. munensis has large tooth sockets towards the back of its mouth, which indicates that it may have possessed large teeth that could have been capable of crushing shells. As a result of this, they suggest that A. munensis may have eaten hard-shelled prey, such as snails, in addition to other animals.  

The findings provide further insight into the evolution of Asian alligators.

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Article details

An extinct deep-snouted Alligator species from the Quaternary of Thailand and comments on the evolution of crushing dentition in alligatorids

DOI: 10.1038/s41598-023-36559-6

Please link to the article in online versions of your report  

https://www.nature.com/articles/s41598-023-36559-6

The timekeeper within: New discovery on how the brain judges time

Peer-Reviewed Publication

CHAMPALIMAUD CENTRE FOR THE UNKNOWN

Rat with hourglass 

IMAGE: SCIENTISTS ARTIFICIALLY SLOWED DOWN, OR SPED UP, PATTERNS OF NEURAL ACTIVITY IN RATS, WARPING THEIR JUDGEMENT OF TIME DURATION. view more 

CREDIT: CREATED BY HEDI YOUNG WITH THE ASSISTANCE OF STABLE DIFFUSION



From Aristotle’s musings on the nature of time to Einstein’s theory of relativity, humanity has long pondered: how do we perceive and understand time? The theory of relativity posits that time can stretch and contract, a phenomenon known as time dilation. Just as the cosmos warps time, our neural circuits can stretch and compress our subjective experience of time. As Einstein famously quipped, “Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute”.

In new work from Champalimaud Research’s Learning Lab published in the journal Nature Neuroscience, scientists artificially slowed down, or sped up, patterns of neural activity in rats, warping their judgement of time duration and providing the most compelling causal evidence so far for how the brain’s inner clockwork guides behaviour.

In contrast to the more familiar circadian clocks that govern our 24-hour biological rhythms and shape our daily lives, from sleep-wake cycles to metabolism, much less is known about how the body measures time on the scale of seconds to minutes. The study focused precisely on this seconds-to-minutes timescale at which much of our behaviour unfolds, whether you’re waiting at a stop light or serving a tennis ball.

The Population Clock Hypothesis

Unlike the exact ticking of a computer’s centralised clock, our brains maintain a decentralised and flexible sense of time, thought to be shaped by the dynamics of neuronal networks dispersed across the brain. In this “population clock” hypothesis, our brains keep time by relying on consistent patterns of activity evolving in groups of neurons during behaviour.

Joe Paton, the study’s senior author, likens this to dropping a stone into a pond. “Each time a stone is dropped, it creates ripples that radiate outward on the surface in a repeatable pattern. By examining the patterns and positions of these ripples, one can deduce when and where the stone was dropped into the water”.

“Just as the speed at which the ripples move can vary, the pace at which these activity patterns progress in neural populations can also shift. Our lab was one of the first to demonstrate a tight correlation between how fast or slow these neural ‘ripples’ evolve and time-dependent decisions”.

The researchers trained rats to distinguish between different intervals of time. They found that activity in the striatum, a deep brain region, follows predictable patterns that change at different speeds: when animals report a given time interval as longer, the activity evolves faster, and when they report it as shorter, the activity evolves more slowly.

However, correlation does not imply causation. “We wanted to test whether variability in the speed of striatal population dynamics merely correlates with or directly regulates timing behaviour. To do that, we needed a way to experimentally manipulate these dynamics as animals reported timing judgements”.

Unravelling Time with Temperature

“Never throw away old tools”, smiles Tiago Monteiro, one of the study’s lead authors. To establish causation, the team turned to an old-school technique in the neuroscientist’s toolbox: temperature. “Temperature has been used in previous studies to manipulate the temporal dynamics of behaviours, such as bird song. Cooling a specific brain region slows down the song, while warming speeds it up, without altering its structure. It’s akin to changing the tempo of a musical piece without affecting the notes themselves. We thought temperature could be ideal as it would potentially allow us to change the speed of neural dynamics without disrupting its pattern”.

To test this tool in rats, they developed a custom thermoelectric device to warm or cool the striatum focally, while simultaneously recording neural activity. In these experiments, the rats were anaesthetised, so the researchers employed optogenetics - a technique that uses light to stimulate specific cells - to create waves of activity in the otherwise dormant striatum, much like dropping the stone into the pond. Notes co-lead author Margarida Pexirra, “We were careful not to cool the area too much, as it would shut down activity, or warm it too much, risking irreversible damage”. They found that indeed cooling dilated the pattern of activity, while warming contracted it, without perturbing the pattern itself.

“Temperature then gave us a knob with which to stretch or contract neural activity in time, so we applied this manipulation in the context of behaviour”, says Filipe Rodrigues, another lead author in the study. “We trained animals to report whether the interval between two tones was shorter or longer than 1.5 seconds. When we cooled the striatum, they were more likely to say a given interval was short. When we warmed it, they were more likely to say that it was long”. For example, heating up the striatum sped up striatal population dynamics, similar to accelerating the movement of a clock’s hands, causing the rats to judge a given time interval as being longer than it really was.

Two Brain Systems for Motor Control

“Surprisingly”, adds Paton, “even though the striatum coordinates motor control, slowing down or speeding up its patterns of activity doesn’t correspondingly slow down or speed up the animals’ movements in the task. This got us thinking more deeply about the nature of behaviour control in general. Even the simplest organisms face two fundamental challenges when it comes to controlling movement. First, they have to choose from among different potential actions - for instance, whether to move forward or backward. Second, once they’ve chosen an action, they need to be able to adjust and control it continuously to ensure it’s carried out effectively. These basic problems apply to all kinds of organisms, from worms to humans”.

The team’s findings indicate that the striatum is critical for resolving the first challenge - determining ‘what’ to do and ‘when’ - while the second challenge of ‘how’ to control the ongoing movement is left to other brain structures. In a separate study, the team is now exploring the cerebellum, which houses more than half of the brain’s neurons, and is associated with continuous, moment-by-moment execution of our actions. “Interestingly”, Paton reveals, “our preliminary data shows that applying temperature manipulations to the cerebellum, unlike the striatum, does affect continuous movement control”.

As Paton points out, “You can see this division of labour between the two brain systems in movement disorders like Parkinson’s and cerebellar ataxia”. Parkinson’s, a disease that affects the striatum, often hampers patients’ ability to self-initiate motor plans, such as walking. Yet providing sensory cues, like lines of tape on the ground, can facilitate walking. These cues likely engage other brain regions, such as the cerebellum and cortex, which are still intact and can effectively manage continuous movement. By contrast, patients with cerebellar damage struggle with executing smooth and coordinated movements, but not necessarily with the initiation or transition between movements.

Implications and Future Directions

By providing new insights into the causal relationship between neural activity and timing function, the team’s results may advance the development of novel therapeutic targets for debilitating diseases such as Parkinson’s and Huntington’s, which involve time-related symptoms and a compromised striatum. Additionally, by highlighting a more specific role for the striatum in discrete, as opposed to continuous, motor control, the results could also influence algorithmic frameworks used in robotics and learning.

“Ironically, for a paper about time, this study was years in the making”, remarks Monteiro. “But there’s plenty more mystery to unravel. What brain circuits create these timekeeping ripples of activity in the first place? What computations, other than keeping time, might such ripples perform? How do they help us adapt and respond intelligently to our environment? To answer these questions, we’re going to need more of something we’ve been studying…time”.