My dessert competition entry for my workplace Christmas party last year: eggnog cheesecake. The tough judges from HIMB, like those on TV cooking shows, were scoring looks as well as taste, so I had to go all out!
I have a particular fondness for cooking competitions. Whether it be Iron Chef (the original and the American spinoff), Cupcake Wars or Chopped, once the burners are lit, I can’t seem to look away. Over time, I’ve come to notice that all cooking shows tend to incorporate the same elements when it comes to judging. Taste, of course, is paramount. Creativity and surprise seems to rank high as well. But almost as important as the dish itself, whether a chef is competing in Hell’s Kitchen or on Top Chef, is how it looks. Called presentation or plating, it incorporates everything from the colors of the food to what dish, bowl or glass it’s served in.
Don’t get me wrong — I like pretty things. Some of the stuff these chefs whip up could just as easily belong in the Louvre as on my dinner table. But I never really understood why presentation is so important. Who cares if it looks like Alpo if it tastes delicious? I simply didn’t get the obsession with the visual — until, that is, I began to read the research of scientists like Vanessa Harrar and Charles Spence.
Taste, they have found, is in the eye, ear, and hand of the beholder.
In a study published today in the open access journal Flavour, Harrar and Spence show that even something as overlooked as our cutlery can change our perception of foods.
Facebook gleefully reported earlier this week that their privacy practices are “A-Ok”, in response to the growing federal concerns that the company leaks too much personal information. While it’s all well and good that they are legally in bounds, users still worry about just how much is shared via the popular social networking site. After all, just what does your Facebook activity say about who you are?
Our voices communicate information far beyond what we say with our words. Like most animals, the sounds we produce have the potential to convey how healthy we are, what mood we’re in, even our general size. Some of these traits are important cues for potential mates, so much so that the sound of your voice can actually affect how good looking you appear to others. Which, really, brings up one darn good question: what makes a voice sound sexy?
Beer gets into our heads, even before the alcohol has time to kick in. Image credit: 123RF Stock Photo
I remember quite vividly the first time I tried beer — I almost spit it out. Bitter, bubbly and generally bad, I didn’t get why everyone seemed to be so enamored with it. Yet I, like so many people in the world, continued to drink it. Have you ever wondered why we, as a species, consume alcoholic beverages even though they taste terrible at first?
A new study suggests that despite the bitter taste, the chemicals in beer trigger the brain’s reward system. This pleasurable effect might just explain why we’re so willing to keep drinking past the first sip — until intoxication takes over, and we’ll drink just about anything. But more importantly, this new research, published today in the journal Neuropsychopharmacology, may explain why some people can drink casually while others slip into alcoholism. Continue reading “Brain’s reaction to the taste of beer helps explain why it’s hard to stop at one”
Caffeine has been a part of human cultural heritage for more than five thousand years. From ancient teas and coffees to todays energy drink craze, you could say that as a species, we’re hooked. But we’re not the only ones — a new study published in Science today has found that pollinators get a daily buzz off caffeine, too, and it keeps them coming back for more.
Take a moment to look at yourself in the mirror. I want you to really examine your features—the curves, lines and shapes that make up your face. How broad is your chin? Narrow, or wide? How big is your mouth in comparison? Or your nose? Do you have strong, prominent eyebrows? How close are they together?Just look at this face. Do you trust me? A new study in PLoS ONE says you might, even though you don't know why.
Or, more simply, what color are your eyes?
In a study published today in PLoS ONE, researchers from from Charles University in the Czech Republic had 238 participants rate the faces of 80 students for trustworthiness, attractiveness, and dominance. Not surprisingly, they found that the three measures correlated well with each other, with faces rating high on one scale rating high on the other two. Female faces were generally more trustworthy than male ones. But that’s wasn’t all. A much more peculiar correlation was discovered as they looked at the data: brown-eyed faces were deemed more trustworthy than blue-eyed ones.
It didn’t matter if the judge was male or female, blue-eyed or brown-eyed. Even accounting for attractiveness and dominance, the result was the same: brown-eyed people’s faces were rated more trustworthy. There was some evidence of in-group bias, with blue-eyed female faces receiving lower ratings from brown-eyed women than from blue or green-eyed ones, but this difference didn’t drive the phenomenon. All the participants, no matter what eye color they had or how good-looking they thought the face was agreed that brown-eyed people just appear to look more reliable.
The real question is why? Is there a cultural bias towards brown eyes? Or does eye color really correlate somehow with personality traits like accountability and honesty? Does eye color really matter that much?
To find out, the scientists used computer manipulation to take the same faces but change their eye colors. Without changing traits other than hue of the iris, the researchers swapped the eye colors of the test faces from blue to brown and vice versa. This time, the opposite effect was found. Despite the strange correlation to eye color, the team found that eye color didn’t affect a photo’s trustworthiness rating. So it isn’t the eye color itself that really matters—something else about brown-eyed faces makes them seem more dependable.
To get at what’s really going on, the researchers took the faces and analyzed their shape. They looked at the distances between 72 facial landmarks, creating a grid-like representation of each face. For men, the answer was clear: differences in face shape explained the appeal of brown eyes.
Shape changes associated with eye color and perceived trustworthiness, from the grid-based facial shape analysis done by the researchers. Note the similarities between the shapes of brown-eyed faces and trustworthy ones.
“Brown-eyed individuals tend to be perceived as more trustworthy than blue-eyed ones,” explain the authors. “But it is not brown eyes that cause this perception. It is the facial morphology linked to brown eyes.”
Brown-eyed men, on average, have bigger mouths, broader chins, bigger noses, and more prominent eyebrows positioned closer to each other, while their blue-eyed brethren are characterized by more angular and prominent lower faces, longer chins, narrower mouths with downward pointing corners, smaller eyes, and more distant eyebrows. The differences associated with trustworthiness are also how our faces naturally express happiness—an upturned mouth, for example—which may explain why we trust people who innately have these traits.
Although the trend was the same for female faces, researchers didn’t find the same correlation between trustworthiness and face shape in women. This result is puzzling, but female faces were overall much less variable than male faces, so it’s possible the statistical analyses used to test for correlation were hampered by this. Or, it’s possible that something else is in play when it comes to the trustworthiness of female faces. The researchers hope that further research can shed light on this conundrum.
Given the importance of trust in human interactions, from friendships to business partnerships or even romance, these findings pose some interesting evolutionary questions. Why would certain face shapes seem more dangerous? Why would blue-eyed face shapes persist, even when they are not deemed as trustworthy? Are our behaviors linked to our bodies in ways we have yet to understand? There are no easy answers. Face shape and other morphological traits are partially based in genetics, but also partially to environmental factors like hormone levels in the womb during development. In seeking to understand how we perceive trust, we can learn more about the interplay between physiology and behavior as well as our own evolutionary history.
Citation: Kleisner K., Priplatova L., Frost P. & Flegr J. (2013). Trustworthy-Looking Face Meets Brown Eyes., PLoS ONE, 8 (1) e53285. DOI: 10.1371/journal.pone.0053285
There’s a lot to be said for smarts—at least we humans, with some of the biggest brains in relation to our bodies in the animal kingdom, certainly seem to think so. The size of animal brains is extravagantly well-studied, as scientists have long sought to understand why our ancestors developed such complex and energetically costly neural circuitry.
One of the most interesting evolutionary hypotheses about brain size is The Expensive Tissue Hypothesis. Back in the early 1990s, scientists were looking to explain how brain size evolves. Brains are exceedingly useful organs; more brain cells allows for more behavioral flexibility, better control of larger bodies, and, of course, intelligence. But if bigger brains were always better, every animal would have them. Thus, scientists reasoned, there must be a downside. The hypothesis suggests that while brains are great and all, their extreme energetic cost limits their size and tempers their growth. When it comes to humans, for example, though our brains are only 2% of our bodies, they take up a whopping 20% of our energy requirements. And you have to wonder: with all that energy being used by our brains, what body parts have paid the price? The hypothesis suggested our guts took the hit, but that intelligence made for more efficient foraging and hunting, thus overcoming the obstacle. This makes sense, but despite over a century of research on the evolution of brain size, there is still controversy, largely stemming from the fact that evidence for the expensive tissue hypothesis is based entirely on between species comparisons and correlations, with no empirical tests.
With beauty and brains, Poecilia reticulata help give insights into cognitive evolution
A unique study published this month in Current Biology has taken a new approach to examining this age old question. Rather than comparing species with bigger brain-to-body ratios to smaller-brained relatives, they exploited the natural variation of brain size in guppies (Poecilia reticulata). Guppies, as it turns out, aren’t as dumb as they look. They’re able to learn, and show rudimentary ability to count. Researchers from Uppsala University in Sweden were able to use their numerical abilities to test whether brain size affects intelligence in these simple fish.
Fig. 2 from the paper; Large-brained females outperform small-brained females in a numerical learning task. Depicted are the mean and standard error values for the number of times, out of eight tests, that an individual chose the correct option of either two or four objects in females and males selected for large and small brain size.
First, the team selected for larger and smaller brains from the natural variation in guppies. They successfully created smarty-pants guppies that had brains about 9% larger than their counterparts through artificial selection. Then, they put them to the test. While the males seemed to gain no benefits from possessing larger noggins, the females with bigger brains were significantly better at the task.
But what was really remarkable was the cost of these larger brains. Gut size was 20% smaller in large-brained males and 8% smaller in large-brained females. The shrunken digestive system seemed to have serious consequences reproductively, as the smarter fish produced 19% fewer offspring in their first clutch, even though they started breeding at the same age as their dumber counterparts. And, the authors noted, this was in an idealized tank setting with an plenty of food—what about in the wild, where resources are harder to come by? How much of a cost does a reduced gut have when meals aren’t guaranteed?
“Because cognitive abilities are important to facilitate behaviors such as ?nding food, avoiding predation, and obtaining a mate, individuals with increased cognitive abilities are likely to have higher reproductive success in the wild,” explain the authors. These benefits, though, don’t come cheap. “Our demonstration of a reduction in gut size and offspring number in the experimental populations selected for larger relative brain size provides compelling experimental evidence for the cost of increased brain size.”
There are still many questions to be answered. For example, the authors aren’t entirely sure why females were the only ones to show cognitive improvement with larger brains. They suggest that, perhaps, the researcher’s measure of intelligence (the numerical task presented to the guppies) may be be geared toward female behaviors. “In the guppy, females are more active and innovative while foraging,” they explain. “Because females feed more, they may thus have had more time to associate the cue with food in our experimental design.”
The clear trade-off between brains and guts, though, is an important finding. By providing empirical evidence for the physiological costs of brains, this study provides the ?rst direct support for the expensive-tissue hypothesis, and can provide us with insights into how our own big brains evolved. One of the prevailing hypothesis for our own brain growth is that the incorporation of more animal products into our diets, through hunting or cooking or however, allowed us to obtain more energy from less food, thus offsetting the cost of a reduced gut. The less food we needed to eat for the same amount of energy, the more our brains could grow even if our guts suffered for it. The debate, however, is far from over. Comparative analyses in primates don’t support a gut-brain tradeoff, and there are certainly plenty of other hypothesis as to how and why we developed our massive lobes, and what prices our bodies paid for them.
Kotrschal A., Rogell B., Bundsen A., Svensson B., Zajitschek S., Brännström I., Immler S., Maklakov A. & Kolm N. (2013). Artificial Selection on Relative Brain Size in the Guppy Reveals Costs and Benefits of Evolving a Larger Brain, Current Biology, DOI: 10.1016/j.cub.2012.11.058
Einstein once said that the definition of insanity is doing the same thing over and over while expecting different results. Yet as scientists, we are taught to fundamentally question this assumption. We replicate and repeat with the express purpose of determining if a result is reproducible or merely the product of random chance. As social and emotional creatures, we do the same thing. We like to believe in second chances. We tell ourselves that stochastic circumstances are to blame when things don’t go the way we imagined, so when presented with the opportunity to try again, we often do. Or, at least, I do. But no matter how logical an argument I can make for do-overs, Einstein was right.
In retrospect, I feel like a fool. As I sit at the edge of my bed fumbling with my guitar, I can’t help but blame myself. Why did I choose time and again to trust a person whose actions have always betrayed it? Blinded by love, I had a slew of reasons, a variety of parameters I could change that I thought might affect the outcome. But now, with 20-20 hindsight, I cannot find any. I should have known better, I chide myself. I failed the scientist in me.
Yet still at the slightest mention of him, I flush with anger, jealousy and regret, and heart pounding, I fantasize about retaliation and justice. Evolutionary psychologists would tell me that the physiological experience of betrayal stems from the fact that humans, at our core, are a social species. Personal bonds were vital to our ancestors, and thus natural selection has reinforced emotional mechanisms that evaluate the connections we form with others. In a dangerous world, our ancestors had to know whom they could trust with their lives. Anyone who threatened the relationships we have with one another didn’t just wound pride or break hearts, they threatened our predacessors very survival. The reaction is strong and visceral: stress hormones spike, leading to twisting pain in our gut and heightened sensitivity. But at the same time, areas of our brain involved in deception detection activate. While we feel the rush of cortisol and adrenaline clouding our thinking, brain regions like the anterior insula process our physical and emotional state to make judgements of trustworthiness to inform future interactions.
If only my previous judgements had been more permanent. A friend of mine likes to say “monkeys learn,” but clearly, I didn’t the first time. Though the rest of our evolutionary lineage seems to be quick to categorize friends from foes, I could not.
What’s done is done, though, and I am left to collect the pieces of my heart that they shattered so effortlessly. While I might not have learned my lesson as quickly as I should have, I have learned it now. I know that this time is different. There will be no more replicates, no more re-runs with the hope of a different result. There are no variables I can change to get what I want. The data are clear, and it’s time to stop trying to bias them toward the end I prefer. All that is left is to document what happened, so like a good scientist, I write and record my final results.
Music has a remarkable ability to affect and manipulate how we feel. Simply listening to songs we like stimulates the brain’s reward system, creating feelings of pleasure and comfort. But music goes beyond our hearts to our minds, shaping how we think. Scientific evidence suggests that even a little music training when we’re young can shape how brains develop, improving the ability to differentiate sounds and speech.
The answer from a study just published in the Journal of Neuroscience is a resounding yes. The team of researchers from Northwestern University’s Auditory Neuroscience Laboratory tested the responses of forty-five adults to different complex sounds ranging in pitch. The adults were grouped based on how much music training they had as children, either having no experience, one to five years of training, or six to eleven years of music instruction.
Music training had a profound impact on the way the study subjects’ brains responded to sounds. The people who had studied music, even if only for a few years, had more robust neural processing of the different test sounds. Most importantly, though, the adults with music training were more effective at pulling out the fundamental frequency, or lowest frequency sound, of the test noises.
“The way you hear sound today is dictated by the experiences with sound you’ve had up until today,” explained co-author and lab head Nina Kraus. As she and her colleague wrote in an article for Nature, “akin to physical exercise and its impact on body fitness, music is a resource that tones the brain for auditory fitness.”
There is a body of research that suggests music training not only improves hearing, it bolsters a suite of brain functions. Musically trained kids do better in school, with stronger reading skills, increased math abilities, and higher general intelligence scores. Music even seems to improve social development, as people believe music helps them be better team players and have higher self-esteem. “Based on what we already know about the ways that music helps shape the brain, the study suggests that short-term music lessons may enhance lifelong listening and learning,” said Kraus. “Our research captures a much larger section of the population with implications for educational policy makers and the development of auditory training programs that can generate long-lasting positive outcomes.”
The importance of music education is something to consider, given that election season is in full swing. According to a recent White House report, more than 300,000 education jobs have been lost since the “end” of the recession in 2009 – 7,000 were lost last month alone. As schools lose funding, arts and extracurricular programs are often first on the chopping block, meaning less music education for the nation’s youth. Given the scientific evidence supporting the importance of music both neurologically and educationally, the loss of music education seems particularly painful. Perhaps as we head to the polls this season, we should give even more thought as to how our choices of elected officials might affect the education system in this country and the brains of the children who are its future.
Citation: Skoe, E. & Kraus, N. (2012). A Little Goes a Long Way: How the Adult Brain Is Shaped by Musical Training in Childhood, Journal of Neuroscience, 32 (34) 11510. DOI: 10.1523/JNEUROSCI.1949-12.2012
There’s nothing in this world so sweet as love. And next to love the sweetest thing is hate.
– Henry Wadsworth Longfellow
I stare hard into his hazel eyes. Those damned eyes. I blink, and I’m bombarded with flashes of those eyes through lenses of love, trust, fear and anger. My blood is pumping with passion, sped on by norepinephrine and vasopressin. The neurons in a round structure at the base of my forebrain are firing like crazy, a cacophony of neural activity. I glance down at his lips. Half of me wants to kiss him – half of me wants to break his jaw.
Part of the problem is that for intense emotions, my body reacts in a similar way. Heart rate and blood pressure skyrocket, driven by stress hormones. My muscles tense. My palms sweat. My cheeks flush. Objectively, it might be hard to tell what I am feeling. Subjectively, it’s hard, too.
Love him or hate him, two regions of my brain – the putamen and the medial insula – activate when I look at his face. Some have suggested that since the putamen regulates motor functions and contains neurons that activate when we plan actions, perhaps it is helping me decide between that punch and that kiss, but there seems to be more going on. The putamen is highly regulated by dopamine, one of the neurotransmitters linked to intense romantic feelings and the messenger of our neurological reward system. I smirk at the idea that, perhaps, I just find the thought of cold-cocking him deeply rewarding.
It is the activation of the insula, though, that is most intriguing. The insula is a bit of a neurological slut, and is intimately involved in our experience of number of basic emotions, including anger, fear, disgust, happiness and sadness. Scientists believe the insula acts as a translater, connecting sensations in our bodies to emotions in our brains. The insula turns a bad taste into disgust, or a gentle touch into arousal. But what makes the insula so interesting is that many believe these connections go both ways. Not only are my feelings affecting my body, the very act of processing my body’s reaction to the situation – my fast pulse, shallow breaths, sweaty palms – is changing how I feel.
As my sensations surge, parts of my cortex responsible for judgement and reason shut down – love and hate really are blind in that way. Studies have suggested love is more blind, though, as larger areas of the cerebral cortex deactivate. I know my thoughts aren’t logical anymore. They’re at the mercy of neurotransmitter tides, waxing and waning. Confusion is an understatement.
I blink hard and try to focus.
Even my hormones are flirting with both sides of the emotional spectrum. The flushed skin, pounding heart and rapid breathing are the fault of norepinephrine and adrenaline kicking on my fight or flight instinct. Passion is passion, and the same hormonal system is triggered by fear, anger, lust and desire. Whatever the fueling emotion, my body is primed, ready to spring into action.
Similarly, the anger-pumping hormone testosterone has a romantic side. Testosterone levels strongly control feelings of lust and desire, but more importantly, women falling in love have higher circulating testosterone. Thus even a hormone so intertwined with agression and hate is instrumental in my experience of romance and pleasure. I briefly wonder if the increased testosterone level in my body is having side effects as I clench my fist.
Sure, love and hate have their differences, too. The giddy, happy romantic feelings come from different parts of the brain than deep passion. But as the intensity of the emotion rises, the fine line between love and hate blurs. It’s no wonder philosophers have been lumping them together for centuries, two sides of the same coin. As glorified as our idea of love might be, passionate love has the same biomarkers as addiction and obsessive compulsive disorder – and like with addiction and obsession, when the stakes are high, the smallest thing can push a person over the edge.
He shouldn’t have pushed me.
My amygdala turns on. Today, the dark side wins. I close my eyes as aggression ripples through my body. I didn’t want a fight, but my body disagreed. Rage fueled by love overwhelms me. It takes everything in my power not to fly at him. Feeling my self-control waning, I clench my teeth. Then, slowly, I open my eyes to see his have hardened, too. Alright, then. Here we go.
Facebook gleefully reported earlier this week 
Music has a remarkable ability to affect and manipulate how we feel. Simply listening to songs we like 
I stare hard into his hazel eyes. Those damned eyes. I blink, and I’m bombarded with flashes of those eyes through lenses of love, trust, fear and anger. My blood is pumping with passion, sped on by norepinephrine and vasopressin. The neurons in a round structure at the base of my forebrain are firing like crazy, a cacophony of neural activity. I glance down at his lips. Half of me wants to kiss him – half of me wants to break his jaw.
