transcript of episode 3: THE BRAIN: A Lâ¤VE STORY, 12th February 2021
welcome to the error bar: where the brain bull is de-horned
in this episode: how social media posts betray relationship breakdown, how lonely brains are different, and the quest for the brain's beauty centre
here is the brain news on the 12th February 2021:
[🎶 BIG BEN BONGS 🎶]
LANGUAGE LEAKS LOST LOVE
the Mail and the Times report on a study of the language people use when they are about to go through a breakup.
the study by psychologists in Texas, USA used computer text mining to analyse more than a million posts on the social media site Reddit, in a particular subsection about relationship break ups.
the text analysis identified a decrease in the use of analytical - or problem-solving - thinking, increases in more emotional cognitive processing, and increased use of the personal pronouns 'I' and 'we'.
the authors claim that such methods help understand the emotional upheavals of relationship breakups; the newspapers claim that people about to break up change the way they speak.
[🎶 INTERLUDE 🎶]
can the language we use betray our failing relationships?
while the headlines state that we can use our partner's language to warn us of an impending breakup, the evidence is not so clear-cut.
first, this study used the large, freely-available dataset of Reddit, a social media site on which all users and posts are public and can be fully anonymous. none of the users, relationships, or stories were, or can be, verified for truthfulness. and they were dredged for data.
second, the researchers targeted a section of the site called BreakUps. and they only looked at users who went to that site for the first time, presumably to post about their relationship break up.
third, the authors assumed that the time of the first post was also the time of the breakup. they only actually read two hundred of the 1,027,541 posts. of those 200, only 121 gave an indication of the break-up time, and of them, the majority - 98 - said it was within the previous 2 weeks. so, fewer than half of the relatively small sample of posts said that the breakup was recent. so any claims that language can predict break ups are impossible to verify.
fourth, while the headlines and claims are about 'people' in general, two thirds of Reddit users are male, and typically young. this is reflected in the very patchy and unreliable demographics of the study 'participants': an estimated 70% were male, 67% had been dumped, the average age was 23, and average relationship length was 2 years.
fifth, despite containing millions of datapoints, dozens of variables tested, and looking at each variable over every single 2-week period over 2 years, there is no proper treatment of the statistical problems of false-positives - due to many tests being done - or of auto-correlation - the fact that the same people are providing data at many different time-points, and the number of people changes at each time-point.
finally, even if the results stand up, the introduction contains contradictory predictions about the usefulness of the 'analytic' type of thinking - the authors predicted on page 1 that people deciding to leave a relationship should increase their analytical thinking, but on page 2 that people will decrease their analytic thinking as a breakup occurs. page 2 lists a long "set of hypotheses" that are all a little vague. who starts a study with a set of hypotheses.
overall: this study has the faint but familiar smell of a deep sea fishing expedition.
a self-selected group - largely of anonymous young men who have been dumped - make their first post on a social media site about break ups. the posts are not very analytical & say 'i' & 'we' a lot. nothing here about the brain
the science was by Seraj et al. 2021: Proceedings of the National Academy of Sciences of the United States of America; reported in The Daily Mail by @shivalibest on 1/Feb/21, & The Times by @rhysblakely on 2/Feb/21
[🎶 BIG BEN BONGS 🎶]
LONELY BRAINS LOOK DIFFERENT
Canada's Globe and Mail reports on a brain imaging study that looks at the structure and activity of thousands of brains stored in the UK's biobank database.
within that database, nearly 40,000 people had several different kinds of brain scans of both the structure and the activity of the brain at rest. each of these people had also answered a simple question: do you often feel lonely?
since the average age of participants was 55, this question taps into trait loneliness - people who have been feeling lonely for some time.
these 40,000 brains were analysed using sophisticated computational and statistical methods.
the researchers found that a set of brain regions known as 'the default network' was strongly associated with people's response to that one question - do you often feel lonely?
indeed, the amount of grey matter in this brain region was strongly associated with loneliness, as were the relationships between activity in this region and other regions. finally, some white matter pathways emerging from the hippocampus - which is an important part of the brain associated with memory - were also associated with loneliness
[🎶 INTERLUDE 🎶]
does loneliness change your brain?
the authors of this study used sophisticated methods on the very large database of brain scans that they analysed.
there was just a single question asked of the participants: do you often feel lonely, which they answered yes or no. and all of the complex data analysis was focussed on the relationship between that single answer and the brain.
like most papers reviewed here, it is outside my specific expertise. however, this paper strikes me as a high quality bit of science. there are clear signs of goodness here:
the research paper uses the word "uncertainty" no fewer than six times - we love uncertainty at the error bar; it uses robust statistical methods that take account of the inherent biases in and limitations of the dataset.
phrases like bootstrapping, Bonferroniâ€™s correction, and Monte Carlo simulation in this paper really do make our hearts sing.
this is quality science reporting both from the Globe and Mail, and from the scientists. we celebrate it.
a sophisticated, thorough and cautious analysis of a massive, high-quality dataset answers a very simple question: does feeling lonely change the brain? yes, it seems it does
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BEAUTY IS IN THE BRAIN. OR ISN'T
in case relationship breakups and the brain basis of loneliness weren't enough to bring you down, Scientific American reviews a brain imaging study published in October last year, concluding that there is no 'beauty centre' in the brain
the researcher team from China, Germany and Scotland, searched for all of the published studies that had scanned peoples' brains while they were looking at beautiful things like art, or people's faces, and compared them to less-beautiful things
comparing beautiful and less-beautiful things in each study had resulted in some areas of the brain being more active than others
combining all the faces and all the arts studies revealed two regions of common responsiveness - one for faces and one for arts
the face beauty region was in the prefrontal cortex - that's an important part of the brain that we heard about in the last episode to do with obsessive compulsive behaviours
the art beauty region was, err, also in the prefrontal cortex, but a slightly different location
there was no overlap at all - there is no 'beauty' region in the brain
[🎶 INTERLUDE 🎶]
is there really no brain area for beauty?
no, sorry. and the study seems to be quite sensible and reliable, statistically-speaking
but if you really want to find a brain area for beauty - if that will make you happy - then you can cling on to some unavoidable drawbacks of this kind of meta-analysis:
the meta-analysis is only as good as the individual studies that were included in it, and no specific assessment of study quality was reported
and the meta-analysis was based only on the peak activations in each study, rather than all of the raw data. if you need there to be a common brain area for beauty, then you can hope that all the missing brain activity would somehow sum up to create a brain blob for beauty
looking at images and considering how beautiful they are will produce consistent responses in specific parts of the brain. but those parts depend on the kind of images. there's no brain area for beauty
[🎶 BIG BEN BONGS 🎶]
LOVE IS IN THE (UNDERARM H)AIR
the most remarkable thing about this story is that it did NOT appear in any of the newspapers this week. yet this study is tabloid gold. i am starting to wonder whether science journalists check pubmed every week like the error bar does.
somewhere in Aachen, Germany, 5 ovulating and 5 pregnant women had 2 nights' worth of their underarm sweat mopped up and refrigerated.
these sweatpads were then placed under the noses of 18 young, single, heterosexual, cisgender men in a brain scanner while they looked at pictures of women's faces.
after inhaling the sweat for 3.5s, the single men rated the attractiveness of the pictures, or they guessed whether the depicted woman was pregnant or not (it was not mentioned if the women in this standard image database were pregnant or not).
the young men's attractiveness ratings or pregnancy guesses did not differ substantially after smelling the ovulating women's sweat compared to the pregnant women's or to a neutral one.
but the brain did seem to distinguish the women's armpits: after smelling the ovulating women's sweat, several regions in the, [checks notes], medial orbitofrontal cortex responded more than for the pregnant womens' pits.
[🎶 INTERLUDE 🎶]
can the brain smell ovulation?
the study seems to be a fairly standard, well-conducted brain imaging experiment - there's nothing obviously amiss in the methods or analysis, and the authors have been quite honest in laying out their hypotheses and finding that most of them were not supported.
so yes, on the face of it, the brain's orbitofrontal cortex - which seems to be the error bar's favourite brain area - does seem to distinguish between the sweats of ovulating and pregnant women.
while there were no strong differences in the attractiveness ratings of the photographs under the different smell conditions - photos were rated an average of '6' on the scale - the differences between conditions were in the hypothesised direction, so the behavioural part of this study may have been a bit underpowered.
the only obvious caveat about the study is that the 5 ovulating women who provided sweat were an average age of 24, while the 5 pregnant women were an average of 30 - and this is a substantial statistical difference. why such an obvious confound was not controlled in this expensive, quite invasive study, is not known. perhaps the brain can smell the age, rather than ovulation?
as for the brain imaging part: the error bar finds it intriguing that in the last episode the orbitofrontal and medial prefrontal cortex were associated with learning about reward, and in this episode it is associated with the perception of beauty in a meta-analysis of 49 studies, and the difference between ovulating and pregnant women in a single sweat-smelling study.
i think we've found St Valentines brain area.
let's hope the British tabloids do not find this study.
single young men's brains seem to distinguish between the smells of a group of similarly-aged ovulating women & the smells of an older group of pregnant women. science is a little bit larger now, but perhaps not much better.
the science was by Habel et al. 2021: NeuroImage;
and the brain in brief...
[🎶 BIG BEN BONGS 🎶]
THERE'S TOO MUCH BRAIN NEWS
DOGS LEARN LANGUAGE
MUSICIANS HAVE SUPERBRAINS
PROBITY'S AUDIBLY PERCEPTIBLE
WRITING PREDICTS ALZHEIMERS
TREES REDUCE DEPRESSION
SMOG IMPAIRS COGNITION
CANNABIS REDUCES INTELLIGENCE
TOUCHSCREENS DISTRACT TODDLERS
RISK-TAKERS BRAINS DIFFER
ELON MUSK EXAGGERATES
LIGHT HELPS READING
pour me a pint
the science was by Fugazza et al. 2021: Scientific Reports, Leipold et al. 2021: Journal of Neuroscience, Goupil et al. 2021: Nature Communications, Eyigoz et al. 2020: EClinicalMedicine, Marselle et al. 2020: Scientific Reports, Russ et al. 2021: Journal Of Alzheimer's Disease, Portugal et al. 2021: Scientific Reports, Power et al. 2021: Psychological Medicine, Aydogan et al. 2021: Nature Human Behaviour, & Rahimi-Nasrabadi et al. 2021: Cell Reports; reported in The Times by @rhysblakely on 27/Jan/21, & The Independent by @_tombatchelor on 26/Jan/21, & The Daily Mail by @RyanMorrisonJer on 25/Jan/21, & The Daily Mail by @RyanMorrisonJer on 8/Feb/21, & The New York Times by @ginakolata on 1/Feb/21, & The Independent by Joe Middleton on 26/Jan/21, & The Daily Mail by @RyanMorrisonJer on 3/Feb/21, & The Daily Mail by @RyanMorrisonJer on 28/Jan/21, & The Daily Mail by @jwillchad on 26/Jan/21, & The Daily Mail by @RyanMorrisonJer on 28/Jan/21, & Herald Sun by Noah Manskar on 3/Feb/21, & The Daily Mail by @shivalibest on 2/Feb/21
[🎶 BIG BEN BONGS 🎶]
LEWIS WOLPERT (1929-2021)
the Guardian & Telegraph carried the obituary of Professor Lewis Wolpert who passed away in January.
while not a brain scientist, Wolpert published an acclaimed book & communicated widely on the critically important subject of depression, doing much to remove the stigma of mental ill-health. i saw him talk about his book in london in 1999 & re-read it this week.
in what must be one of the most powerful introductions to a neuroscience book, he wrote:
"it was the worse experience of my life. more terrible even that watching my wife die of cancer. i am ashamed to admit that my depression felt worse than her death but it is true. i was in a state that bears no resemblance to anything I had experienced before. it was not just feeling very low, depressed in the commonly used sense of the word. i was seriously ill. i was totally self-involved, negative and thought about suicide most of the time. i could not think properly, let alone work, and wanted to remain curled up in bed all day. i could not ride my bicycle or go our on my own. i had panic attacks if left alone. and there were numerous physical symptoms - my whole skin would seem to be on fire and i developed uncontrollable twitches. every new physical sign caused extreme anxiety. i was terrified, for example, that i would be unable to urinate. sleep was impossible without sleeping pills: these only worked for a few hours, and when i woke up i felt worse. the future was hopeless. i was convinced that I might go mad."
that was the striking first paragraph of Malignant Sadness by Professor Lewis Wolpert
rest in peace
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the error bar was devised & produced by Dr Nick Holmes from University of Birmingham's School of Sport, Exercise and Rehabilitation Sciences. the music by Dee Yan-Kee is available from the free music archive. find us at the error bar dot com, on twitter at bar error, or email talk at the error bar dot com.ε