“It ain’t over till the [XS, S, M, L, XL] lady sings…”

Most people are probably familiar with the quote in the title of this post.

However, it’s usually written “It ain’t over till the fat lady sings”.  While metaphorically, it means, “don’t assume anything has ended till it’s actually ended…” (which I suppose is a pretty meaningless tautology), it’s rooted in the stereotype of an overweight opera singer, an often referenced image being from Wagner’s operas, particularly Brünhildes’s final tome that ends Götterdamerung (which itself completes Wagner’s four opera Ring Cycle).

Sucher_BruennhBeGK

Rosa Sucher, Bavarian soprano as Brünnhilde, in Berlin

Being an opera singer/scientist (specifically with a physiology background), I get asked the following questions A LOT*:

  • Does being “fat” help you to be a better opera singer?
  • Why are/were so many famous opera singers “fat”?
  • Did Maria Callas’ voice ‘go south’ because she lost so much weight?

I’ve put “fat” in inverted commas, because currently, I think we have a messed up view of what “fat” is, what “healthy” means and far too often both of those terms are morally, socially and psychologically loaded, so “fat” will be in reference to an amount of adipose tissue (the fancy science word for “body fat” as opposed to say, muscular tissue), over a threshold, that can start to put one’s health at risk for diseases and physical complications.

Are we all OK with that definition? Good, then read on…

So that you’re not left in suspense, the simple answers to the questions above are:

  • No. Nope, nyet, non, nein, no.
  • Too many factors to arrive at a singular, simplistic answer and
  • Probably not, no, though it makes great urban legend…

A specific amount of fat, in either direction, or rather one’s dress/suit size in and of itself has absolutely no benefit or detriment to the technique of classical/operatic singing, none, not a sausage. To be a technically proficient singer, you must first learn, among other techniques, to control the breath, most specifically exhalation and maintaining breath pressure during singing.  Then you have the formation of pure vowel sounds followed by an endless checklist of skills around musicianship, stage craft, languages, movement etc..

Breathing is nothing to be sniffed at, it’s fundamentally the core of good of any good technique and requires a host of muscles working in virtuosic coordination, while letting other muscles (both involuntary and voluntary) remain ‘neutral’ (i.e. not get in the way of the muscles doing the work). It’s simultaneously simple and like patting your head and rubbing your stomach at the same time, in rhythm, and in Russian, or something.

Without going into a lengthy explanation of breathing technique, it boils (no pun intended) down to muscularly applying Boyles Law to breath control.  From a muscular perspective, we’re primarily concerned with rapid engagement and disengagement of muscles of the torso, which requires both strength and balance.  This “control” and subsequent flexibility, is what is referred to as “appoggio“, (from the Italian appoggiarsi a, ‘to lean upon’, this in itself is often misinterpreted in execution, but the fundamental principle is sound) which came into technical prominence during what’s called the Italianate school of Bel Canto.

While we are obviously breathing into our lungs when talking or singing, we are controlling the flow and pressure of those respiratory gasses muscularly.  The use of these muscle groups can be helped or hindered by things as simple as posture and alignment, but it essentially is the thoracic and abdominal muscles which must (as we say in the biz) work like stink. The muscles we’d be most concerned with for singing (simplistically, in this instance), would be the obliques and the transverse abdominus (specifically that last puppy).

As you can see from the diagram (which also appears in one of the BEST books on physiology anyone could own, it was my undergrad bible), the transverse abdominis is three layers deep, this is NOT a superficial muscle that will get you an enviable six pack as seen on what are called Barihunks. Instead this muscle is key in both thoracic and pelvic stability, which for a singer will contribute to a feeling of expansion and a kind of groundedness minus a feeling of “pushing”. This muscle also needs to stay flexible to adapt to rapid intake of air while maintaining the established expansion for “support” (now you can see where the patting head/rubbing stomach comes in).

So how does your body size come into this equation? Well, it does and it doesn’t. Because the muscle you need the most is quite deep, you do need to be able to feel it working, if you are a larger person with a less-toned abdomen, that may not be as obvious, depending on how you’ve been taught to experience “appoggio”. You may also find that because you don’t have a particularly “muscular” frame, you feel it more easily as the movement of this muscle should be flexible and rapid (try panting like a dog with your hands in the region of the transverse abdominis and see what you feel).

I’ve heard singers say “you can’t sing well if you have a six pack”, that’s flat out incorrect.  As with the example above of having fat over the transverse abdominis, as long as the transverse abdominis has flexibility and stability, the superficial muscles should not preclude good technique.  If the muscles are too tight, then yes, that can inhibit the range of motion for the transverse abdominis, but then you’re not training yourself correctly.

One thing I feel is VERY important (and I say this as a singer, voice teacher, and qualified fitness instructor and breath specialist), if you gain or lose a significant amount of weight, or change your muscle mass drastically, YOU MUST RE-TRAIN VOCALLY AS THIS HAPPENS.  It’s tempting to think singing is all about the vocal cords, but it’s imperative that all singers take on the mantle of ‘the whole body as instrument‘, not in terms of looks (though that can play) but because every muscle matters and your neurological connection to language and movement is paramount to your craft.

Via http://www.phillymag.com/g-philly/2014/05/29/barihunks-singers-will-make-hit-high-notes/

Barihunk, Nathan Gunn via Philly Mag

When you lose or gain large amounts of weight (or muscle mass), you are fundamentally changing your instrument and your technique must adapt to those changes, you can’t assume everything will fall into place. with your new bod. Your instrument is now different, and you must learn work with it and most likely re-train it.

This is also the more likely reason for what some say was a decline in Callas’ singing as she went from “zaftig” to “svelte”.  Do we know if she was re-training during what was a drastic and rapid weight loss (tapeworm induced or not)? The truth is, we’ll never know the exact reason, and in fact, to some it’s no more than urban myth that she got worse as she slimmed down.  Now this is a whole other post for a day when I feel like torturing myself, but the legend of La Divina ruffles feathers like few other issues in the opera world, however she’s credited as doing her “best work” at nearly every size that she ever was!

So, no, being “fat” or not has very little bearing on whether or not you will be a good singer.  Many teachers will say a general level of fitness regardless of size, is far more important.  Some singers who have had successful careers and have also been what would be considered very overweight have taken drastic measures to slim down.

Most recently American soprano, Aprile Millo spoke on her facebook very candidly about how being obese has affected her career and well being.  There was also well meaning, but incorrect, Dame Kiri te Kenawa who stated that “singers need a bit of beef on them” in order to sing.  While this is not factually correct, this is probably more an example of reactions to the sizeism that continues to plague opera.

There’s nothing that physiologically should stop a slim and trained woman singing, let’s say, Brünnhilde, but I do agree with Kiri that NO ONE should be altering their body and therefore their voice to look a certain way for a role.

Like I said before, your body is your instrument. Treat it well!

A singer should be well trained, and healthy whatever their size. The fact that this has become controversial in opera in recent years, well, that’s another blog post, innit…

In closing, here’s me talking with the outstanding Naked Scientists a bit more about the science behind singing.

And because I’m feeling generous here’s an amazing takedown by the Goddess herself on why size in opera is, well, bollocks, I give you the amazing, inimitable, formidable, larger than life and fabulous (yeah, I”m a fan) Jessye Norman.

*DISCLAIMER: NOTHING in this piece is meant to serve as vocal instruction, medical advice, or fitness advice. This is an exploration of a popular myth that won’t die and some facts about physiology to back up my observations. Do what you will with that information…

Surviving the Festive Season Part One: What makes it so stressful?

schrokit:

REBLOGGED FROM: London Central Counselling

Originally posted on London Central Counselling:

This is the first in a series of posts about getting through the holiday period. Christmas is the festival I grew up with, and the one that is the hardest to miss in the UK as it approaches, but I think much of this could apply to any other celebration where people come together over a holiday period who might not normally spend time with each other.

Needless to say, if you totally and unequivocally love these festive times, and find my question above odd or incongruous, these posts may not be for you. But you may know someone who might find them useful.

So, why does the holiday season affect so many of us so badly? And why do we continue to let it?

Positives
There are lots of potentially enjoyable things about festival periods. I am pro end-of-year (or any other time) coming together in front of fires, candles, dancing and wearing sparkly clothing…

View original 1,150 more words

How is an opera singer like a physicist?

No, that’s not the opening of a joke…

In fact, fun as it is, operatic singing is by no means easy, and opera is not ONLY about singing.*

An opera singer is expected to be (ideally, in equal measures) a musician, a linguist, an athlete (let’s not kid ourselves, opera is an endurance sport in many ways), an actor, a movement artist (no, you can’t just stand there and do nothing, even standing still can have artistry) and let’s not forget the ‘making nice sound with the voice ‘ bit…

“There is a saying in the Neverland that, every time you breathe, a grown-up dies.” 
― J.M. Barrie, Peter Pan

Despite wishing death on adults (though that quote is more about the eternal child living…), one hopes, that in normal everyday life, you tick along not thinking about your breathing.  At all. That’s because the autonomic nervous system takes care of that for you.

When a singer begins training, usually, one of  the first things addressed is breathing, or rather getting control of one’s breathing. This involves the manipulation of some muscles, the relaxation of others, and essentially overriding the autonomic nervous system’s default settings for breathing (or homeostasis, if you like fancy science words).

Having recently started studying with new teacher myself, we went back to the beginning in our first few sessions, as she wanted to check my understanding of how I was using my breath, breath management and the muscles involved in managing the whole show.

As we started discussing the language around breathing and what’s often referred to ‘breath support’ (it’s actually not my favourite term as it’s too easy to misinterpret, but I’ll rant about that another time), we talked about the expansion of body that occurs in parts of the thoracic cavity in terms of both capacity and pressure.

And then it hit me, I was applying…

BOYLE’S LAW!

This was the first time I saw, and quite literally felt my science and singing education(s) come together.

When breathing for operatic singing (or just, you know, respiration), we’re applying PHYSICS, which is so exciting, and specifically for a singer, it’s a deliberate manipulation of that air pressure and rate of expenditure of the respiratory gasses (c’mon, you KNOW ‘respiratory gasses’ sounds sexy).

So what is Boyle’s Law?

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Unhelpful to non scientists/mathematicians squiggly equation image via Wikipedia

Very simply, the pressure of a given quantity of a gas is inversely proportional to its volume, at a constant temperature, (and actually ONLY works as an ideal, but it’s a good guideline).

So, even more simply put: less volume, more pressure.

Or more specifically: if volume is halved, pressure is doubled.

Why is this important for singing?

To summarise that second video, breathing (deliberately pwith ‘technique’, or not) alters both the pressure and capacity within the thoracic cavity.

When you inhale you increase the volume of gas in the lungs (obvs), and at the same time this decreases the total pressure within the lungs, the pressure OUTSIDE the body is greater at this point.

When you exhale, muscles of the thoracic cavity relax and the pressure resulting from the muscular activity sends the air out, reducing the overall internal volume.

What a singer needs to do when sustaining long singing phrases (or even short ones) is manage and get in control of the amount of air released and the use of both the increase and decrease of pressure.

HOW one does that from a technique perspective is another kettle of fish altogether (and as my disclaimer says, I’m not giving a singing lesson here…). So instead of going down that road, I’ll just leave you with a fierce example of singing with incredible breath control, Montserrat Caballe’s Casta Diva from Bellini’s Norma:

 

*Disclaimer: this post in no way constitutes vocal instruction, or advice, it’s merely relating my personal collision of opera and science.  As such, anything written in this blog is for informational purposes only!

 

I’m the worst blogger in like, forever!

Hello readers!

Yes, I’m perhaps the laziest blogger in all of bloggerdom (not really), but I have excellent excuses. I finished my Pharmacology & Physiology degree, started graduate studies in molecular psychiatry (schizophrenia research), started my own business (woop!) and am doing a wee bit more of that there opera stuff.

Despite not blogging much, I did have a wee piece in the Guardian Science section the other week.  So while I try to restart the part of my brain that needs to blog, please enjoy (or not) this:

Demystifying Detox: Can yoga really cleanse the liver?

Schrokit out :-)

Not so innocent?

Food Fruits and Berryes The delicious berries and fruits 222This is probably old news to many you, but I only found out/realised/ woke from a coma yesterday to notice that Innocent Smoothies (among other packaged smoothie brands) are pasteurised. Having been foodless all day due to food poisoning (I may never trust a bramley apple sausage again) I finally decided to brave something late in the day. The Innocent Smoothie had come free with my grocery order the night before, and I thought, well, given I’ve lost a lot of fluid, nutrients etc., that this would be a reasonable option, and easy on the tummy!

At first I thought the smoothie was already past its expiry date (hey, when food attacks you, you pay more attention to things like that), but LO! the expiry date on this FRUIT smoothie was MAY 9th, not APRIL 9th. Clearly, I’m naive to the ways of BIG SMOOTHIE*, as when I examined the bottle more closely it states that it is, in fact, pasteurised. More specifically, flash pasteurised, which relies on heating the juice (or as one paper called it, the SUBSTANCE, mmmmm, I love a yummy SUBSTANCE) at ~ 100 degrees celsius, for shorter periods of time than ultra heat pasteurised (UHT) ‘substances’, so somewhere in the region of 15 – 30 seconds.

From a public health and safety POV, flash pasteurisation is a good thing, killing harmful bacteria and also extending the life of the juice. Quite a few companies have been doing it since the middle of the last century, but it in the wake of the raw foods**, preservative free surge of the mid 1990s, some juice makers, like Odwalla (originally of Half Moon Bay, California, now of Coca Cola) went properly naked, if you will, and sold un-pasteurised juices to be as close to ‘raw’ and ‘fresh’ as possible. This nutritionally well intentioned choice turned fatal when a 16 year old died from the apple juice that was a key ingredient in numerous Odwalla products.

Today in the US, all store bought juices must be pasteurised. The only way to get a properly fresh juice or smoothie is to do it yourself or go to a fancy schmancy fresh juice bar. If neither is an option and you go for bottled what are you getting? The short answer is a lot of sugar and likely, fewer nutrients than you would from fresh.

Manufacturers argue that flash vs UHT is better for the consumer in terms of nutrient retention though the overal benefit seems to be in a better and more ‘natural’ tasting juice/smoothie. A 2009 study from Rutgers University showed a much greater loss of raw materials (antioxidant, anthocyanin and total phenolic content) in juices processed to become frozen concentrate compared to flash pasteurisation (Skahill, 2009) but as the substances underwent further processing to become ‘beverages’, the retention between the two methods was insignificant.

Another recent study hypothesised that it’s more likely the method of extraction and ‘finishing process’ that have a greater effect on the final product than pasteurisation in terms of taste and quality, and should be studied further as many manufacturers search in anger a for closer to ‘fresh-squeezed’ option (Baldwin et al., 2011). Still, some feel that the nutritional loss from any pasteurisation method is worth eliminating where possible and current exploration is focussed around alternate processes like microfiltration, which may further retain the integrity of the fruit and its nutritional value (de Oliveira et al., 2012).

So while flash pasteurisation isn’t a completely evil thing, if you’re a vegan or a rawist (or whatever), it’s likely the pasteurisation process won’t meet your standards of purity and ethics. If you’re going for maximum nutrition, you’re probably out of luck with a bottled smoothie, as the thing that seems best retained is the sugar from the fruits. Sure, it’s OK in a pinch, but I’m hard pressed (fnar) to accept that a 250mL bottle of an Innocent whatsit smoothie *really* gives you ‘two of your five a day’ (another concept that’s problematic, but I digress…) what with any pasteurisation process involved. Your best bet is still homemade or the fancy juice bar round the corner. Or hey, go the totally non fuss way and EAT THE FRUIT WHOLE. Crazy, I know… ;-)

A former personal trainer of mine once gave me the advice of “don’t drink your calories”, and much as I love a smoothie now and then, from a nutritional standpoint, I could’t agree more.

* OK, I don’t really believe in a BIG SMOOTHIE conspiracy, stop sending me tin foil…

** raw foodists advocate not cooking any food above 40 degrees celsius

References

Baldwin, E. A., Bai, J., Plotto, A., Cameron, R., Luzio, G., Narciso, J., et al. (2012). Effect of extraction method on quality of orange juice: hand-squeezed, commercial-fresh squeezed and processed. Journal of the Science of Food and Agriculture, 92(10), 2029–2042. doi:10.1002/jsfa.5587

Skahill, B. A. (2009). Effects of Thermal Processing on Antioxidant, Phenolic and Anthocyanin Levels in Blackcurrant Juice Rutgers, The State University of New Jersey, 1–67.

de Oliveira, R. C., Docê, R. C., & de Barros, S. T. D. (2012). Clarification of passion fruit juice by microfiltration: Analyses of operating parameters, study of membrane fouling and juice quality. Journal of Food Engineering, 111(2), 432–439. doi:10.1016/j.jfoodeng.2012.01.021

A happy and ‘Fast’ 2013!

Firstly, a big thank you to all the readers, followers and especially comment contributors of Shrokit’s Corner. You’ve driven up my blog stats :-) but more than that, you’ve kept an interesting conversation going both here and on twitter, and that’s been really rewarding for me as a fledgling blogger.

Those of you who found your way here via the BBC Horizon site, hungry for more info on 2:5 fasting after watching the programme Eat, Fast, Live Longer may well know that Dr Mosley has come out with a new book: The Fast Diet

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What you may not know, is that this little old blog is featured in it (though I’ve not seen the end product, so I don’t know by how much – if anyone has a copy already, do let me know), and that’s no small thanks to the discussions inspired in the comments section.

As far as my own progress, in early January I’ll be getting back into the Bod Pod and having BGL and cholesterol levels checked. Unfortunately, I’ve not gotten around to checking my IGF-1 levels, for a variety of reasons, but hopefully that will be remedied in the new year (I’m still open to offers of free tests ;-)).

In the meantime, I would like to wish you all a very Happy New Year and I look forward to more discussion in 2013!

I’m so full, I can barely move… Now, what’s for dinner?

I briefly checked in to Twitter during a self-imposed hiatus (because, let’s face it, I’m an addict and when there’s something really cool on io9 I have to share it with my fellow Twitizens) and noticed a tweet by article82, that echoed the sentiment of a lot of folks this time of year:

It’s almost endemic to the festive season what with the abundance of large traditional meals, office parties and a general feeling of eat, drink and be merry. Hyperbolic headlines aside, the British Dietetic Association estimates that the average caloric excess at this time of year is an additional 500 cals per day, which depending on how early the “holiday” eating begins (and continues consecutively) can potentially add up to an extra 5lbs to contend with when the new year starts.

But why do we overindulge, or rather, despite sating ourselves through hedonic eating (that is, for pleasure and not just for nutrition) why do we keep topping up?

Short, lazy, oversimplified answer might be: blame your hypothalamus (naughty, naughty hypothalamus, it always wants something…)

The longer, non-definitive, more complicated, multifactorial explanation involves the hypothalamus, some melanocortins, dopamine, leptin, serotonin, ghrelin, reward centres of the brain that relate to addiction, light-dark cycles, alcohol consumption and host of other external, behavioural influences that will vary from person to person, culture to culture. And maybe tryptophan. Simple, no? (/sarcasm)

OK, there are a lot of crazy words and concepts there, so I’ll try to boil it down a bit and focus on the most prominent bits**, we’ll start with the hypothalamus: The pleasure centre, the passion palace, the seat of seduction (ooh er missus) of the brain.

What’s going on under the hood?

squishy bits in your head via wikipedia

squishy bits in your head via wikipedia

The hypothalamus (meaning, cleverly ‘under thalamus’) resides in the diencephalon of the forebrain in us human types. For such a tiny thing (most descriptions say it’s approximately the size of an almond) it has a huge influence and in some instances, immense control over a myriad of physiological functions, among these are impulses relating to hunger, thirst and sexual desire. The regulating of hunger falls under the remit of balancing the body’s energy needs and keeping the brain powered with glucose. Appetite is largely managed by two parts of the hypothalamus, the ventromedial which tells you when you’re full or satisfied and the lateral hypothalamus from where the sensation of hunger originates [1].

The ‘need to feed’, in and of itself is more intricate than that, but appears to be triggered by neurons in the hypothalamus that detect a drop in the hormone leptin, which is released from fat cells called adipocytes. The inverse appears to be true that with high leptin release levels, the desire to eat gets turned off. There are some theories floating around that when humans are well-fed, the sensitivity to leptin levels becomes dulled, which could be one piece of the ‘overeating’ puzzle [2].

But it’s so yummy!

I bake pies. Conveniently, Mr Schrokit eats pies. And he always has the same reaction to them after eating: MOAR (sic). Now, knowing what I put in them, after a couple of slices, I can’t imagine the leptin levels in his bloodstream are lacking, and one would assume that some anorectic peptides (oversimplified translation: the brain’s in house appetite suppressants) would be saying, “no really, mate, we’re good *burp*. Pardon”. But parts of his midbrain, like the ventral tegmental area, are all, “hey, dude, the party doesn’t have to end, there is more pie, after all…”.

This response to pleasurable and tasty food is not unlike that of potentially addictive drugs, triggering brain reward circuitry by being both rewarding (in taste) and reinforcing (it feels good, why NOT have more), by releasing dopamine from the midbrain.

To quote Mr Schrokit in one of his finer moments, “Dopamine monkey wants more dopamine”. Indeed. While similar to drug addiction, the kind of dependence and tolerance overeating creates, develops over extended periods of time, there is some evidence to suggest that it can also be triggered by binge eating events, and from diets rich in high fat foods [3] [4][5].

Hedonic eating cycle: Adapted from AlsiÃ, J., Olszewski, P. K., Levine, A. S., & Schiöth, H. B. (2012). Feed-forward mechanisms: Addiction-like behavioral and molecular adaptations in overeating. Frontiers in Neuroendocrinology,

Hedonic eating cycle: Adapted from AlsiÃ, J., Olszewski, P. K., Levine, A. S., & Schiöth, H. B. (2012). Feed-forward mechanisms: Addiction-like behavioral and molecular adaptations in overeating. Frontiers in Neuroendocrinology,

What? My cooking’s not good enough for you?!

Apologies, I appear to be channeling my dearly departed Gran (who perfected ‘guilt’, so the rest of you are merely pretenders). She was also a feeder! Aside from taking it as a (joking) affront on her cooking, having grown up during the great depression, she couldn’t imagine why anyone would ever waste food. If she cooked it, you were damn well eating it (no, not the brussell sprouts again…). So even though you were stuffed full to your eyeballs, nan (or mum or auntie) gave you that “look”, and thus you had the second, third etc. helping.

Maybe the holidays with your family is really frelling*** stressful :-( and that triggered a cascade of ‘emotional eating’ [6]. Maybe your resolve to not have that umpteenth mince pie was weakened by that last glass of mulled wine, and you threw caution to the wind. Whatever the reason, your environment, peer pressure and the mood you’re in can very much have an impact on your eating behaviour. You could just simply be relaxed, feeling deserving of some gastronomy fuelled indulgence… vowing to tackle the Crimbo Bulge on January 2nd, or was it the 22nd? Or maybe it was July 2nd, anyway, screw it, it’s the holidays, baby!

Clear as mud?

Far from a simple pat explanation, it’s clear that the physiology, pharmacology and pyschology of eating is no easy matter. And no wonder finding cures for weight gain, eating disorders and obesity (or the behaviours that lead to these states) is both confounding and compelling. Again, I’m aware I’ve glossed over a good deal of detail in favour of digestible amounts of info, but like i said, if you’d like seconds…

And just cause it’s the holidays, a picture of a brain I drew:

Brain, by Schrokit, age 39 (at time of drawing)

Brain, by Schrokit, age 39 (at time of drawing)

** this is simply to say, yes, it’s very very intricate and complicated, and there are a lot of details/specific pathways I’m leaving out in my summary, however, if anyone wants more, I’m happy to go deeper and geekier for you. Yes, I’m that giving ;-)

*** yeah, I’m finally watching Farscape

References:

[1] Holt, R IG, Hanley, N. A., (2007) Endocrinology and Diabetes 5th Edition, Blackwell Publishing, pp 254 – 255

[2] Bear, M.F, Connors,B.W., M.A., Paradiso; (2007) Neuroscience: Exploring the Brain, 3rd Edition, chapter 16 pp 510 – 515

[3] Berridge, K. C., Ho, C.-Y., Richard, J. M., & DiFeliceantonio, A. G. (2010). The tempted brain eats: Pleasure and desire circuits in obesity and eating disorders. Brain Research, 1350(C), 43–64. doi:10.1016/j.brainres.2010.04.003

[4] AlsiÃ, J., Olszewski, P. K., Levine, A. S., & Schiöth, H. B. (2012). Feed-forward mechanisms: Addiction-like behavioral and molecular adaptations in overeating. Frontiers in Neuroendocrinology, 33(2), 127–139. doi:10.1016/j.yfrne.2012.01.002

[5] Wise, R. A. (2012). Dual Roles of Dopamine in Food and Drug Seeking The Drive-Reward Paradox. Biological Psychiatry, 1–8. doi:10.1016/j.biopsych.2012.09.001

[6] Doğan, T., Tekin, E. G., & Katrancıoğlu, A. (2011). Feeding your feelings: A self-report measure of emotional eating. Procedia – Social and Behavioral Sciences, 15, 2074–2077. doi:10.1016/j.sbspro.2011.04.056