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Our perception of time can depend on a number of factors – what we’re doing, how much we’re focusing on it, how we’re feeling. But there's also quite a bit of variability between us in our individual sense of time passing.

Researchers at Oxford University have investigated what plays a part in our perception of short, fleeting times of under a second.

In a new paper published today in the Journal of Neuroscience, they show that levels of a chemical in the brain – a neurotransmitter called GABA – accounts for some of the difference in our perceptions of subsecond intervals in what we’re seeing.

Oxford Science Blog asked Dr Devin Terhune of the Department of Experimental Psychology about the study. So depending on who you are and your judgement of time, if you have somewhere between 2 and 5 minutes to spare, read on.

OxSciBlog: Why is perception of time important to understand?
Devin Terhune: Our ability to perceive duration is one of the most fundamental features of conscious experience and thus it is of great importance to our emerging understanding of how the brain generates consciousness. Second, time perception is necessary for a wide range of abilities, from playing sports and musical instruments to day-to-day decision-making. Studying time perception has considerable potential to greatly inform the broader domains of psychology and neuroscience.

OSB: What can influence time perception?
DT: A variety of factors can affect our perception of time. Two common factors are attention and emotion. If we focus on something, time seems to slow down somewhat (hence the common phrase 'a watched kettle never boils'), whereas it seems to go by faster if we're daydreaming or thinking about something else. In contrast, we tend to overestimate time when we’re frightened, or underestimate it when we’re experiencing joy.

OSB: Tell us about the sort of time perception you investigated in this study
DT: We studied people's perception of short durations of visual images lasting around half a second.

In the specific task we used, participants were first trained on a particular image that lasted around half a second. Subsequently, they saw the same image for a range of different intervals – some shorter, some longer. Participants were asked whether each image was shorter or longer in duration than the trained interval. This task allowed us to determine whether someone is underestimating or overestimating the duration of the images, as well as their precision in the task. 

OSB: And this judgement of time can be affected by the way neurons in the brain respond to what we are seeing?
DT: A number of studies have recently shown that when neurons in visual regions of the brain 'fire' more strongly, a person is more likely to overestimate the duration of a visual event, whereas when the neurons 'fire' less, they are more likely to underestimate the event. Accordingly, different ways of altering these firing responses may thus affect time perception.

OSB: What did you find?
DT: Our study showed that participants' tendency to under- or over-estimate how long the image lasted was associated with a particular neurotransmitter in the brain known as GABA.

Individuals who tended to underestimate the visual intervals were found to have higher GABA levels in the region of the brain responsible for visual processing.

Importantly, GABA levels in a second region of the brain that supports movement and motor functions were unrelated to time perception. Also, GABA levels in the visual area were unrelated to time perception in a non-visual task.

These results suggest that GABA levels in visual regions of the brain may account for variability in our perception of visual intervals.

OSB: What does this suggest is going on in the brain?
DT: We believe that higher GABA levels results in a greater reduction of the firing of neurons in response to a visual image, leading to underestimation.

OSB: Do we as individuals really differ in how we perceive time and events?
DT: It's intuitive to think that our perception of the world is similar to others, but just like many other conscious visual experiences, there is considerable variability in our ability to perceive time. This variability is more apparent for longer intervals – for instance, we all have friends who say they were only gone for two minutes when it was actually closer to ten. This variability is present for very short intervals too.

OSB: Could this tell us anything about our perception of time in everyday situations?
DT: This finding may account for why some people are better at judging very short durations than others. Since we used particular types of images in the lab, we have to be careful about how much we can generalize. However, these very short intervals are important to a range of tasks. For instance, running to catch a ball requires you to estimate when the ball will arrive in a particular location that you can reach. Similarly, when playing a musical instrument as part of an orchestra or band, it is important that you can accurately judge the specific time at which you need to play a particular note.

OSB: Is it wrong to feel slightly unsettled that what we experience and think to be an accurate representation of time passing may not be?
DT: At first glance, it could be somewhat unsettling. However, in the grand scheme of things, the vast majority of people have decent time perception. It's just that some of us are better than others, just like in a range of other cognitive, motor, and perceptual functions. Some of us have better attention or memory than others, some of us are better at riding bicycles, and so on.

When it comes to spatial learning males are better than females, and bold and shy individuals are better than average ones, at least if you're a lizard.

The findings, from a new study of the Easter Water Skink (Eulamprus quoyii) - a lizard that lives throughout Eastern Australia and can grow over 12cm long - are the first evidence of sexual learning differences in a reptile. A report of the research is published in this week's Proceedings of the Royal Society B.

A team led by Oxford University and Macquarie University, Sydney, scientists took 64 skinks, 32 males and 32 females, and released them into a series of strange environments to investigate how differences in personality influence how they learn. These environments included features they would like, a 'warm' refuge made of a box with three entrances heated by an incandescent bulb, and features they wouldn't, a 'cold' refuge made of a similar box chilled with ice packs.

By introducing the skinks to simulated predator events (being chased away into a refuge) the researchers determined which returned quickly to bask in a warm refuge ('bold' lizards) and which took longer than average to return ('shy' lizards). They then tested the lizards once a day for 20 days in a setting where they were again exposed to simulated predatory attacks and given a choice between a safe refuge (chasing stopped) and an unsafe refuge (the refuge was lifted and chasing continued) that were always located in the same place.

'We found that male lizards were better at this spatial learning task than females, with twice as many males as females learning the spatial task within 20 trials,' explains Pau Carazo of Oxford University's Department of Zoology, who led the research.

'While this is the first evidence ever of sexual learning differences in a reptile, we believe it reflects the fact that males are forced to spend more time moving through their environment in search for females or patrolling their territory to guard it against other rival males. We also show that, across the sexes, the boldest and shyest individuals were overall better learners than intermediate individuals.'

According to the team this is the first evidence that individuals at the extreme ends of a personality axis are better learners than individuals with intermediate personality traits. This does not fit well with current theories about how personality and learning may co-evolve: the team proposes the idea that spatial learning ability and personality are both linked with male reproductive strategies.

'In Eulamprus, as in many other lizard species, male lizards exhibit two alternative reproductive strategies. Some male lizards defend territories, which not only requires them to be bold but also to constantly patrol their territory and remember rival males at its boundaries (which would favour good spatial learners),' Pau tells me.

'In contrast, other males adopt an alternative sneaker strategy whereby they are forced to navigate over long distances (which would also favour good spatial learning abilities) to sneak into other males' territories and try to mate with resident females. Because these males do not defend territories and normally avoid fights, they are likely to be shy.

'We suggest that males that are particularly good at either of these two strategies are likely to be good spatial learners and are either extremely bold or extremely shy individuals. This new hypothesis may help to explain how personality and learning co-evolve, and to understand the evolutionary processes that may lead to the striking individual differences in learning than can be observed in most animal species studied to date.'

The Ashmolean Museum's new exhibition, Cézanne and the Modern, opens on Thursday and will feature 50 masterpieces of late-19th to mid-20th-century European art from the Henry and Rose Pearlman Collection.

Highlights include Paul Cézanne's Mont Sainte-Victoire, Vincent van Gogh's Tarascon Stagecoach and Amedeo Modigliani's portrait of Jean Cocteau, as well as an outstanding suite of 16 watercolours by Cézanne.

Arts at Oxford was given a behind-the-scenes look at the installation of the new exhibition…

Vincent van Gogh – Tarascon Stagecoach (1888)

This painting of the Tarascon stagecoach was produced in the courtyard of the inn at Arles – probably in a single sitting on 12 October 1888. Vincent van Gogh (1853–90), the Dutch Post-Impressionist painter, spent time living and working in Paris and Arles. He is famous for his vivid use of colour and works filled with emotion. Although his artistic career only lasted for 10 years, he was highly prolific and 864 paintings of his have survived, along with many drawings and prints.

Foreground: Édouard Manet – Young Woman in a Round Hat (1877-79); Background: Paul Cézanne – Cistern in the Park of Chateau Noir (c.1900)

Foreground: Édouard Manet – Young Woman in a Round Hat (1877-79)

Édouard Manet (1832–83) lived and worked in Paris, and many of his most famous works depict Parisian society of the 19th century. At the time his paintings were considered controversial, but they are now considered by many as the starting point for modern art.

Manet often used members of his family and close friends as models in his paintings, blurring the conventional distinction between the portrait and the genre picture. Although clearly painted from life, this striking painting is not a conventional portrait, as the woman's face is hidden by a veil and by the shadow of her hat. She is seen in profile, in outdoor dress, ready to leave the apartment or studio where she is depicted.

Wilhelm Lehmbruck – Buste von Frau Anita Lehmbruck (1910)

Wilhelm Lehmbruck – Buste von Frau Anita Lehmbruck (1910)

Wilhelm Lehmbruck (1881–1919) was a German sculptor who studied in Düsseldorf and also in Paris. He worked as a paramedic in a military hospital during World War I, and this had a profound effect on his later sculptures. Lehmbruck created this portrait of his wife during their four-year stay in Paris (1910–14).

Cézanne and the Modern: Masterpieces of European art from the Pearlman Collection runs from 13 March to 22 June 2014.

Images © The Ashmolean Museum and The Henry and Rose Pearlman Foundation.

African elephants make a specific alarm call in response to the danger of humans, according to a new study of wild elephants in Kenya.

Researchers from Oxford University, Save the Elephants, and Disney's Animal Kingdom carried out a series of audio experiments in which recordings of the voices of the Samburu, a local tribe from North Kenya, were played to resting elephants. The elephants quickly reacted, becoming more vigilant and running away from the sound whilst emitting a distinctive low rumble.

When the team, having recorded this rumble [listen to the rumble here], played it back to a group of elephants they reacted in a similar way to the sound of the Samburu voices; running away and becoming very vigilant, perhaps searching for the potentially lethal threat of human hunters.

The new research, recently reported in PLOS ONE, builds on previous Oxford University research showing that elephants call 'bee-ware' and run away from the sound of angry bees. Whilst the 'bee' and 'human' rumbling alarm calls might sound similar to our ears there are important differences at low (infrasonic) frequencies that elephants can hear but humans can’t.

'We concede the possibility that these alarm calls are simply a by-product of elephants running away, that is, just an emotional response to the threat that other elephants pick up on,' Lucy tells me. 'On the other hand, we think it is also possible that the rumble alarms are akin to words in human language, and that elephants voluntarily and purposefully make those alarm calls to warn others about specific threats. Our research results here show that African elephant alarm calls can differentiate between two types of threat and reflect the level of urgency of that threat.'

Lucy King and Joseph Soltis film elephants reacting to Samburu voices

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Significantly, the reaction to the human alarm call included none of the head-shaking behaviour displayed by elephants hearing the bee alarm. When threatened by bees elephants shake their heads in an effort to knock the insects away as well as running – despite their thick hides adult elephants can be stung around their eyes or up their trunks, whilst calves could potentially be killed by a swarm of stinging bees as they have yet to develop a thick protective skin.

Lucy explains: 'Interestingly, the acoustic analysis done by Joseph Soltis at his Disney laboratory showed that the difference between the ''bee alarm rumble'' and the ''human alarm rumble'' is the same as a vowel-change in human language, which can change the meaning of words (think of ''boo'' and ''bee''). Elephants use similar vowel-like changes in their rumbles to differentiate the type of threat they experience, and so give specific warnings to other elephants who can decipher the sounds.'

This collaborative research on how elephants react to and communicate about honeybees and humans is being used to reduce human-elephant conflict in Kenya. Armed with the knowledge that elephants are afraid of bees, Lucy and Save the Elephants have built scores of 'beehive fences' around local farms that protect precious fields from crop-raiding elephants.

'In this way, local farmers can protect their families and livelihoods without direct conflict with elephants, and they can harvest the honey too for extra income,' says Lucy. 'Learning more about how elephants react to threats such as bees and humans will help us design strategies to reduce human-elephant conflict and protect people and elephants.'

Margi Blunden, daughter of the First World War poet Edmund Blunden, will be remembering her father and his work at the WW1 Poetry Spring School run by Oxford University's English Faculty on 3-5 April 2014.

Margi will recall life growing up with a father deeply affected by the Great War and shed light on his literary achievements. As our living link to this bygone age, Margi will provide a thrilling insight into the man who wrote the autobiographical Undertones of War (1928), hailed as Blunden's greatest contribution to the literature of war.

The Spring School is open to members of the public, particularly those who are seeking to challenge common misconceptions and gain a deeper critical appreciation of Great War poetry. It will bring together world-leading experts, each giving an introductory lecture on the major poets and poems. Speakers will provide reading lists and follow-up exercises for further study.

Other speakers confirmed include: Adrian Barlow, Meg Crane, Guy Cuthbertson, Gerald Dawe, Simon Featherstone, Philip Lancaster, Stuart Lee, Jean Liddiard, Alisa Miller, Charles Mundye, Jane Potter, Mark Rawlinson and Jon Stallworthy.

Aged 19, Edmund Blunden volunteered to join the army, despite winning a place at The Queen's College, Oxford to read Classics. He was commissioned as a second lieutenant and went to France in early 1916 and was eventually demobilised in mid-February 1919. During his service in France and Flanders he spent two years at the front, more than any other well-known war writer. Those two years included some of the most violent and bloody fighting in the war, including the battle of the Somme and the battle of Third Ypres.

His most famous works also include In Concert Party: Busseboom (written 10 years after the war) and The Waggoner (1920). He enjoyed a productive career as an editor, journalist, critic and biographer. Blunden was also instrumental in bringing the works of the war poets Wilfred Owen and Ivor Gurney to publication. Edmund Blunden died at his home on 20 January 1974 aged 77.

The Spring School will be held at the Faculty of English, St Cross Building, University of Oxford on 3-5 April 2014. There are a number of different ticket options, including student, senior, school and single-day rates. See the website for full details.