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How voices work: vocal music
Quiz by Maria masters
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They've Got the Beat! Some students in New York really sing their hearts out! That's because they are in the school chorus at Public School 22. These students from Staten Island had a concert at the White House. They sang at a Hollywood awards show. Audiences have clapped and cheered them on. These kids are always asked to return. How does it feel to sing on stage? "I get nervous singing for a big audience," Brianna Crispino recalls. "But when I see the joy on their faces, I get excited." Sounds Good. The P.S.22 chorus is divided into two groups. The sopranos sing high notes. The altos sing lower sounds. Instruments like drums sometimes keep the beat. It's important to keep the rhythm so they make the right sounds together. Most adult choruses have four groups of voices. Here's a look at the number of each type of voice in one adult chorus from Pennsylvania. Musical Expression. Being part of the chorus is hard work. The chorus members won't disagree. They practice for three hours each week. Gregg Breinberg, their teacher, encourages the chorus to use movements. They move their hands to show how the songs make them feel. "They have their own movements because nobody feels music the same way," he explains. The chorus members understand that singing in a chorus is a big job. "We just want to give it our best!" one student says.
Filmic Techniques Based on the work of Brad Smilanich Mis-en-Scene: originally a French theatrical term arrangements of all the visual elements of the stage area in film â âthe contents of the frame and the way those contents are organizedâ include: lighting, costume, dĂ©cor, props, camera movement or distance . . . all photographic decisions etc. Proxemics: Spatial relationship among characters within the mis-en-scene Rule of Thirds: a compositional rule of thumb in painting, design, photography etc. suggests image divided into 9 equal parts with two vertical and two horizontal lines important elements of the mis-en-scene should be placed along these lines and their intersections some suggest aligning with intersections makes for more interesting pictures than just centreing the subject Proxemics Camera Distance: Quite literally, how far the camera is from the subject being filmed The Hand Camera Camera Distance: Quite literally, how far the camera is from the subject being filmed Extreme Close Up: Singles out one small portion of the body or object Used to intensify emotion, or show reaction Camera Distance: Close up Shot: Shows head of character or small significant object Used to show emotions Camera Distance: Medium Shot: shows figures from the waist up allows character to be seen within background Camera Distance: Long Shot: shows figures from feet up similar to the âstageâ in live theatre orients audience to figures within a location or surrounding Camera Distance: Extreme Long Shot: Sometimes called an âestablishing shotâ Panoramic view of an exterior location orients audience to a location Camera Distance: Camera Angle: Cameraâs angle of view relative to the subject being photographed High Angle Shot: looks down on the subject often used to make the subject look small and insignificant (in combination with camera distance) puts the camera (audience) in âpowerâ position Camera Angle: Low Angle Shot: looks up at the subject often used to make the subject look large and powerful puts the camera (audience) in a âsubmissiveâ position Camera Angle: Flat Angle Shot: camera on same plane as the subject feels most ânormalâ to an audience Camera Angle: Canted Shot: frame is unbalanced in relation to the subject may indicate a symbolic unbalance in the character Camera Angle: Camera Movement literally the camera moving with or around or to follow the subjects in the mis-en-scene or frame Camera Movement: Tilting Movement camera moves up or down on a horizontal axis similar to head nodding movement may be used to show subjects relation to surroundings Camera Movement: Panning Movement camera moves side to side on a vertical axis similar to head shaking movement may be used to establish setting Camera Movement: Dolly Movement camera mounted on a vehicle that moves along with the subject (camera moves, not pivots) follows the subject to signify something important Camera Movement: Crane Shot camera mounted on a crane or boom permits camera to move in & out, up & down, backward & forward often used for high aerial establishing shots Misc. Shots: Hand Held: camera carried to seem jerky, giving ârealistic feelâ Push In: camera moves up to a characterâs face to indicate an epiphany (realization) Spiral: camera circles subject for effect End for ELA 20-2 and 10-1 Shot Transitions/Editing: artificial editing done to string together multiple shots to create a narrative scene or sequence a cut is the change from one shot to another usually separated in to âsoftâ and âhardâ cuts Jump Cut: an instantaneous change from one shot to another this can be very natural or may disorient the audience, depending on how it is used Transitions/Editing Swish Pan: A pan where the speed of the camera is so fast that images are blurry used often to connect events in different settings that are connected by time Transitions/Editing Dissolve: transition where one shot gradually dissapears while another shot gradually appears often used to suggest change of setting or long time passage i.e. flashbacks Transitions/Editing Fade In/Out: transition where the shot gradually overexposes to white or underexposes to black often used to suggest a lengthy passage of time or change in location Transitions/Editing Wipe: transition where one shot is gradually eliminated as another shot moves onto the screen can be vertically or horizontally often suggests movement of the camera to another location Transitions/Editing Iris In/Out: transition where one shot gradually appears as an expanding circle in the middle of an old image suggests . . .??? Transitions/Editing Shot-Reverse Shot: one character is shown looking (often off-screen) at another character, and then the other character is shown looking "back" at the first character. Since the characters are shown facing in opposite directions, the viewer unconciously assumes that they are looking at each other. Transitions/Editing Two-Shot: Face-up shot of two people. Often used in interviews, or when two presenters are hosting a show. A "One-Shot" could be a mid-shot of either of these subjects. A "Three-Shot", unsurprisingly, contains three people. Transitions/Editing Shot Transitions/Editing: Sound: used to reflect or enhance what is shown visually on the screen can include dialogue, music, sound effects, voiceover etc. Diegetic Sound: sound that has a source in the world of the story dialogue spoken by characters, sound made by objects, or music coming from a source grounded in the story of the film Non-diegetic Sound: sound that has a source outside the world of the story usually part of the score or the soundtrack Parallel Sound: sound that complements the image shown i.e. romantic music during a love scene Counterpoint Sound: sound that contradicts the âfeelingâ of the image a happy song played while images of graphic violence are portrayed Voiceover: voice of a non-visible narrator laid over the scene often provides some comment about the narrative of the film Sound Bridge: used to âsoftenâ the transition between one scene and another takes sound from the next shot and overlays it on the current shot 2-3 seconds earlier than we see the image Examples of Diegetic/Non-Diegetic: In the first clip, the non-diegetic music changes to diegetic music when the main character moves inside of the convenience store. In the second clip, the âduhn duhn duuuuhâ which often is non-diegetic becomes diegetic because it is the band in the passing bus playing that music! End for ELA 20-1 Lighting: Can be used by a director to: Control the mood of a scene guide a viewerâs eye to a specific place in mis-en-scene Emphasize and de-emphasize elements in frame Add texture and color Make people look beautiful, ugly, sinister, or angelic Standard 3-Point Lighting: uses three lights called the key light, fill light and back light forms the basis of most lighting. once you understand three point lighting you are well on the way to understanding all lighting. Key Light: main light usually the strongest and has the most influence on the look of the scene. it is placed to one side of the camera/subject so that side is well lit and other side has shadow. Fill Light: secondary light is placed on the opposite side of the key light used to fill the shadows created by key softer and less bright than key Back Light: placed behind the subject ; lights it from the rear. provides definition and subtle highlights around the subject's outlines. Separates subject from background provides a three-dimensional look. Standard 3-Point Lighting: http://www.zvork.fr/vls/ Try using this simulator to play with lighting with those 3 points.
Ella, drama student from Sydney, Australia 6.45: I'm not good at getting up early. Three alarm clocks - at 6.30, 6.40 and 6.50. 8.00: Voice training. Important for an actor. 8.45: Gymnastics - I like it. It helps me concentrate better and makes me feel good. 9.30: Singing and dance workshop. It's hard work, but it gives me energy. Music and rhythm. Love it! 11.00: First break-drink, drink, drink- water, of course. No drinks with sugar in them. Makes the body and the mind tired. 11.15: Performance workshop. Hard work. Our teachers are fantastic, but they tell you when you make mistakes! 12.30: Lunch break - I eat nuts and fruit, or a salad at one of the cafés nearby. I never eat carbohydrates, you know, pasta or other heavy stuff. 2.00: A lecture about acting, for example, how to move on the stage, what to do with your hands, etc. Not always easy to concentrate after lunch. 3.30: Short break. I try not to fall asleep. The day has been very firing! 3.45: Voice training workshop, dance and singing. 6.00: Evening rehearsal. We practise for a performance at the end of term. We're doing a musical this term. Hard work and great fun. 9.00: I go home. 10.00: Zzzzl
Nowadays, millions of us are turning to chatbots for emotional support. But can AI ever be capable of empathy? What about the consequences of people seeking emotional support from machines that can only pretend to care? Can the rise of so-called empathetic AI change the way we understand empathy and interact with one anotherïŒ The researchers found that the empathiser must first be able to perceive how the other person is feeling. They must also be affected by those emotions, feel them to some degree themselves, and differentiate between themselves and the other person. On the first point, in recent years, AI-powered chatbots have made progress in their ability to read human emotions. Most chatbots are powered by large language models (LLMs) that work by predicting which words are most likely to appear together based on training data. In this way, LLMs like ChatGPT can seemingly identify our feelings and respond appropriately most of the time. But when it comes to the other criteria, AI still misses the mark in many ways. Empathy is interpersonal, with continued cues and feedback helping to strengthen the empathiserâs response. It also requires some degree of intuitive awareness of an individual and their situation. Consider someone who cries while telling a doctor she is pregnant. If we know her history of trying for years to be pregnant, we can imagine that her tears mean something different than, say, if she didnât want to have kids. Current AIs are incapable of understanding that kind of slight difference in emotion . The big question is whether AI can truly feel human emotions. Some think AIs might one day share our feelings. One approach is to continue enlarging LLMs with ever vaster and more diverse data and integrate multimodal data like facial expressions and voice. By doing this, AI may develop emotional capabilities. Currently, simple versions of these emotion-reading robots already exist. Yet, some scholars argue that you canât really know what sadness is unless you have felt sad. âYou need to have emotions to experience empathy,â says psychologist Michael Inzlicht at the University of Toronto in Canada. Genuine empathy emerges from social interactions and recognizing other minds - a complete phenomenon requiring consciousness , something AI lacks now and likely always will.
Broken windows are covered. Floorboards are patched and doors screwed back on. The road that was ruined by German tanks is shovelled and raked smooth. Boot-shaped bruises turn yellow then fade and disappear. Flowers grow and spread across the ugly German footprints stomped into garden beds. The village looks pretty once more. School stops for the summer and everyone is put to work on the kolkhoz, the village farm. Women and big boys begin harvesting the barley crops in the outer fields. The biggest girls milk the cows, morning and night, and keep the barns clean. Old Nikolay mends ploughs, horse harnesses, pitchforks and scythes in his workshop. Anna Pushinka teaches Yelena and her friends how to get the honey from the beehives that are scattered through the orchards. I am in charge of collecting eggs. My friends Olga and Nina help. Olga and Nina are five, a year younger than me. They are twins and look exactly alike, except Ninaâs nose is a little bit crooked from when she fell out of bed and squashed it sideways on the floor. The hens, ducks and geese wander free in the summer, so collecting eggs is like a treasure hunt and takes hours. Catching the hens for their daily hugs takes even longer, but I think itâs important because hugs make everyone happy and happy hens lay bigger eggs. Olga says Iâm the best hen-hugger in all of Russia. Nina says Iâll be the best cow-hugger, too, when my arms grow longer. But good hugs have nothing to do with the size of your arms. Itâs all to do with the size of your heart. When we are done with the hens, Olga, Nina and I can spend the rest of the day doing whatever we like. We climb the apricot trees, chase squirrels, lie in the meadow marvelling at how hot Ushankaâs black fur becomes in the sunshine, make daisy chains and race little boats of bark in the stream. I teach Olga and Nina the alphabet and we use charcoal to write our letters and our names all over the village â on doors and walls and the freshly cut ends of firewood. In between, I practise my knots. In case the German princemonsters return. I slip into Old Nikolayâs workshop and tie knots in the harnesses hanging on the walls. I wander into gardens where the washing is hung out to dry and tie knots in the laces on pants and smocks. I creep up behind Anna Pushinka and tie knots in her apron strings. I find baling twine in the hay shed and tie my own ankles together. I do such a good job of these last knots that I canât get them undone. I have to jump all the way to Olga and Ninaâs house and ask them to cut me free with their mamaâs knife. At the end of each day, Ushanka and I run out into the distant barley fields to meet Mama. This is my favourite part of the day, because Mama always shouts, âLittle Rabbit!â and smothers my head with kisses. And as we walk home, we sing. Everyone â women, big boys and me. I love to sing. Almost as much as I love to be kissed by Mama. Sometimes one of the boys, Mikhail, has his balalaika with him. He takes the instrument out from beneath the sheaves of barley piled high on the wagon and plays music. We sing about forests and orchards and people who find their true love. As we walk home, arm in arm, my heart fills with happiness and my belly swells with pride that I am allowed to sing along with the big boys. And I can almost forget about the German prince-monsters and their lies about Russia and their big ugly boots. Almost. But today, when Mikhail reaches for his balalaika, I see other things hiding beneath the barley sheaves. Three of the mamas rush forward and cover them up, but itâs too late. I know they are there. Iâve already seen them. Rifles. Lots of rifles. Mikhail hugs his balalaika to his chest and blushes. âSo play!â cries Mama, her voice oddly loud and high. âLetâs play Sashaâs favourite song, âThe Little Birch Treeâ.â So Mikhail plays and everyone sings about the lovely birch tree with its curly leaves and the branches that will be turned into silver flutes. They sing too quickly, too loudly, and as they sing and walk, they cast nervous sideways glances at me. âItâs alright,â I say, when the song comes to an end. âI didnât see the rifles.â Mama nods and smiles, and I know it was the right thing to say. But I did see the rifles. And I think about Yelena wanting to get lots of guns and dynamite for the Partisans so they can shoot the Germans and blow them into thousands of tiny pieces, and Mama looking as though she agreed, and I know this is what the mamas and the big boys are doing. As well as harvesting, they are helping the Partisans. Three days later, I wake before dawn and I am all alone. Yelena is always here beside me when I wake. But not this morning. I climb down from our bed above the stove. Mama is filling a cloth sack with bread. She ties it closed with a piece of string and hands it to Yelena. âStay out of sight,â says Mama. âAnd donât return until after dark.â âWhereâs she going?â I ask. âNowhere,â snaps Mama. âThen why does she need all that bread?â I ask. âThereâs nothing left for us.â Mama baked four loaves last night and she has stuffed them all into the sack. Yelena opens her mouth, but before she can speak, Mama shoves her out the door and sends her on the way to nowhere. Mama turns and stares at me, her blue, blue cornflower eyes wide with worry. âI know,â I say, flopping down on the bench. âI didnât see any bread.â Mama sits beside me and takes my hand. âAnd . . .?â she prods, obviously waiting for more. I puzzle for a while, then say, âAnd I donât have a sister called Yelena.â Mama laughs, softly and with a little bit of sadness around the edges. âSweet Little Rabbit! You do have a sister called Yelena.â âI do?â I ask, now confused. âI havenât seen the rifles or the bread, but I have seen Yelena?â âYes.â Mama smiles and the magic makes me smile, too. And I am glad that Yelena is real because I love her very much. âYelena is real,â Mama explains, âbut she does not carry sacks of bread into the forest for the Partisans.â âOf course not!â I shout, slapping my forehead. âBecause there is no bread!â Mama laughs loudly now, with not a hint of sadness. She hugs me, pressing me against her warm, loving heart, covering my head with kisses. âClever Little Rabbit,â she murmurs, and then, in barely a whisper, âYour papa would be so proud.â When I wake the next morning, Yelena is sleeping beside me, her mouth open, her braided hair unravelling. Mama is serving kasha to a strange woman seated at our table. I crawl down from above the stove and slide along the bench beside her. I stare at her pants, her tunic, the rope she is using as a belt and her big boots. Sheâs dressed like a man! And thereâs a rifle leaning against the wall near the door. âHello,â I say. âIâm Sasha.â The woman doesnât reply. She just shovels down her kasha. I line my four wooden bears along the table in front of her bowl and say, âThese are my bears: Big Bear, Medium Bear, Little Bear and Even Littler Bear.â âHello, Sasha. Hello, bears.â She smiles but she doesnât tell me her name. âWhy are you dressed like a man?â I ask, tugging at the sleeve of her tunic. âBecause menâs clothes make it easier to run and climb and crawl and shoot,â she says. âYouâre a Partisan!â I gasp. âBut sheâs not real,â says Mama, placing a bowl of kasha before me. âIs the kasha real?â I ask. Mama laughs. âYes, Little Rabbit.â Iâm glad the food is real, because Iâm hungry. But Iâm disappointed that the woman is not real. I was going to ask if I could use her rope-belt to tie her ankles together. For practice. But if sheâs not real, then the rope and her ankles arenât either. The woman finishes her kasha, hangs her rifle over her shoulder, kisses Mama on the cheek then slips out the door. I run to the window to watch her leave, but by the time I get there, sheâs gone. Vanished. âBecause sheâs not real,â I whisper. A week later, Mama and I are working in the garden. We sing as we weed between the flowers and pluck caterpillars from the vegetables. Anna Pushinka is picking strawberries in her garden and wanders over. âTaste these,â she says, holding out the basket. Mama reaches in and takes out a fat strawberry and a tiny piece of folded paper. The strawberry goes into her mouth, the paper into her pocket. âWhatâs on the paper?â I ask. âPaper?â Anna Pushinka replies with a wave of her hand. âGoodness, Sasha! Who has money for paper? These are lean times. We must choose between paper for writing and noodles for our soup. And I always choose noodles.â She chuckles and I know the paper is yet another thing that is not real. That night, Mama slips the paper to Yelena, but she drops it on the floor. I pick it up for her, and I see that there are tiny words and numbers written all over it. I wish I could read better. Iâm desperate to know what it says. Or rather, what it doesnât say, because itâs not real. Later, when Mama has tucked us into our bed above the stove and Ushanka has wrapped herself around the top of my head, I ask Yelena, âWhatâs on the paper?â âWhat paper?â says Yelena. âThe paper that isnât real,â I reply. Yelena stares at me, nibbling her lip, then whispers, âA message for the Partisans. Stuff about where the Germans have their headquarters and when their trains are travelling and where they store their ammunition.â âWhy?â âSo the Partisans can blow them up.â Yelena grabs my arm. âBut donât tell anyone. Itâs a secret.â âWhatâs a secret?â I ask. âThe message.â âWhat message?â I say, my eyes wide. Yelena laughs. âGood boy, Sasha.â My belly swells with pride. I know how to play this game. âHow are your knots coming along?â asks Yelena. âGood! Yesterday, I crept into the dairy and tied knots in the apron strings of all the girls who were milking and only one of them noticed. Today, I tied Olgaâs ankles together with Mamaâs embroidery thread and just now, while you were taking a bath, I tied the sleeves of your blouse together in an enormous knot.â Yelena rolls her eyes, then says, âIâll see if I can find you some rope for practising.â âPractising what?â I ask. âYour knots,â she says. âWhat knots?â Yelena, my big sister who is twelve and always serious t
Received: 26 November 2019 Revised: 10 January 2020 Accepted: 19 January 2020 DOI: 10.1111/obr.13005 PEDIATRICS/PHYSIOLOGY Adipokines: A gear shift in puberty DesirĂ©e Nieuwenhuis | NatĂ lia Pujol-Gualdo Amanda J. Kiliaan Department of Anatomy, Radboud university medical center, Donders Institute for Brain, Cognition and Behaviour, Preclinical Imaging Center PRIME, Nijmegen, The Netherlands Correspondence Amanda J. Kiliaan, PhD, Associate Professor, Department of Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Preclinical Imaging Center PRIME, Radboud university medical center, 6500 HB Nijmegen, Geert Grooteplein 21N 6525 EZ Nijmegen, The Netherlands. Email: amanda.kiliaan@radboudumc.nl Funding information Europees Fonds voor Regionale Ontwikkeling (EFRO), Grant/Award Number: BriteN 2016 1 | INTRODUCTION The prevalence of obesity in adolescents and children is increasing in | Ilse A.C. Arnoldussen | Summary In this review, we discuss the role of adipokines in the onset of puberty in children with obesity during adrenarche and gonadarche and provide a clear and detailed overview of the biological processes of two major players, leptin and adiponectin. Adipokines, especially leptin and adiponectin, seem to induce an early onset of puberty in girls and boys with obesity by affecting the hypothalamic-pituitary- gonadal (HPG) axis. Moreover, adipokines and their receptors are expressed in the gonads, suggesting a role in sexual maturation and reproduction. All in all, adipokines may be a clue in understanding mechanisms underlying the onset of puberty in child- hood obesity and puberty onset variability. KEYWORDS adipokines, obesity, puberty 1,2 the age of 5 years were overweight or were with obesity in 2016, and 3 Obesity is defined by an excessive accumulation of white adipose tissue (WAT), and it is often indicated by a body mass index (BMI) 4 above 30. Two main types of adipose tissue were described: WAT and brown adipose tissue (BAT), which differ in morphology and func- 5-7 Ilse A.C. Arnoldussen and Amanda J. Kiliaan contributed equally to this work. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2020 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of World Obesity Federation Obesity Reviews. 2020;21:e13005. wileyonlinelibrary.com/journal/obr 1 of 10 https://doi.org/10.1111/obr.13005 alarming rates. Specifically, worldwide, 41 million children below this number is expected to increase to 70 million in 2025. obesity is associated with various severe health complications, includ- ing increased risk of diabetes mellitus type 2, hypertension, heart dis- eases, and disturbances in sex hormone levels. 5,6 and mitochondria and plays a role in thermogenesis. Adipocytes in tion. BAT consists of adipocytes containing multiple lipid droplets WAT contain only a few mitochondria and a single lipid droplet. Adipose tissue has several functions including the storage of energy, thermogenesis, and the production and secretion of adipokines Generally, two physiological processes, adrenarche and gonadarche, 11,24 Childhood 5,7,8 a key role in puberty onset. Puberty is known as a period through which the body changes physically, being a physiological process resulting in the maturation of children, i.e. they develop sexual characteristics and obtain reproduc- 9,11 Adipokines are involved in a number of physiological processes including blood pressure, metabo- lism, glucose, and vascular homeostasis and may play amongst others 8-10 (hormones, cytokines, and peptides). tive functions. between obesity and puberty,2,12-23 the biological mechanisms under- lying obesity and puberty onset remain unclear. Hereafter, we review in detail the role of adipokines in the onset of puberty in childhood obesity. Although many studies have shown associations 2 | INITIATION OF PUBERTY PHYSIOLOGICAL PROCESSES IN THE interact to regulate the onset of puberty. During adrenarche, the adrenal cortex secretes steroid hormones (including 2 of 10 NIEUWENHUIS ET AL. androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate (DHEAS), androstenedione, and cortisol), insulin-like growth factor, and growth hormone, which contribute to the pubertal insights on new genetic loci (e.g. melanocortin-4 receptor, mitochon- drial carrier 2, and mitogen-activated protein kinase 13) and on sev- eral pathways that regulate the timing of puberty; however, it partly 34 9,24,25 Both adrenarche and gonadarche are involved in the development growth spurt, body odor, skin oiliness, and skeletal maturation. explains puberty timing variation. Thereby, defining the role of 25 adipokines is of importance in elucidating the variability in puberty as the expression of adipokines is sex-specific and is altered with body composition, adiposity, and during growth spurts. Moreover, adipokines and their receptors are expressed in gonads and several brain regions suggesting involvement in the onset of puberty and sex- ual maturation. Lastly, adipokines interfere in processes regulating timing and duration of puberty, for instance in the HPA and HPG axes which are both key players during adrenarche and gonadarche. Involvement of adipokines in the onset of puberty and specifically in individuals with obesity will be further reviewed in the next 2,24 3 | Puberty onset in girls is assessed using different markers, such as thelarche (breast development), menarche (the start of of pubic hair. pituitary-gonadal (HPG) axis is activated,2,26 and several hormones have been identified to participate in the activation of the HPG axis During gonadarche (Figure 1), the hypothalamic- 2,27 Kisspeptin, neurokinin B, and dynorphin are released by specialized including kisspeptin, neurokinin B, dynorphin, leptin, and ghrelin. 28 key regulator of the pulsatile secretion of gonadotropin releasing neurons, the KNDy neurons in the hypothalamus. Kisspeptin is a 29,30 B stimulates, and dynorphin inhibits the release of kisspeptin, which hormone (GnRH) from the hypothalamus. In addition, neurokinin implies that both coordinate a pulsatile release of kisspeptin. 31 Sub- sections. sequently, the activated HPG axis induces the pituitary gland to secrete luteinising hormone (LH) and follicle stimulating hormone (FSH). As a result, gametogenesis occurs, and the gonads will release sex hormones. Consequently, secondary sex characteristics develop including breast development in girls and an increased testicular vol- 2,26,32 is possibly due to differences in levels of body fat, hypothalamic-pitui- THE ONSET OF PUBERTY IN GIRLS ume in boys. The age at puberty onset varies greatly among individuals, which 19 35 menstruation), and pubic hair development. 33 genome-wide association studies have provided important new tary-adrenal (HPA) axis activity, and genetic background. Recent The average age of However, this age differs between cultures and ethnicities, and since 1980, age at menarche is girls at start of menarche is 12.4 years. 36 significantly decreasing. 36-39 F I G U R E 1 Hormonal regulation in the initiation of puberty in boys and girls. The secretion of kisspeptin, neurokinin B, and dynorphin from KNDy neurons initiate the release of gonadotropin releasing hormone (GnRH) from the hypothalamus. This activates the pituitary gland to produce and secrete luteinising hormone (LH) and follicle stimulating hormone (FSH), which in turn stimulate the gonads to produce estrogen and testosterone in girls and boys, respectively 1467789x, 2020, 6, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/obr.13005, Wiley Online Library on [10/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License NIEUWENHUIS ET AL. 3 of 10 T A B L E 1 Summary of included studies Authors Year Country Study Design Primary Outcome Sex Sample Size (n) Age (y) Data Collection Lian et al21 2019 China Cross-sectional Puberty starts earlier in Chinese Han girls with obesity compared with Chinese Han girls with normal weight. Girls 2996 9-19 2012 and 2013 Biro et al12 Lazzeri et al20 2018 USA 2018 Italy Longitudinal Cross-sectional Body mass index had a greater effect on age at menarche than did race and ethnicity. Girls 946 6-16 2004-2014 Li et al23 2018 China Longitudinal For both, boys and girls, a higher BMI (ie, overweight and obese) is associated with earlier onset of puberty Girls Girls Boys Girls 542 Deng et al22 Flom et al15 2017 China Cross-sectional Increased BMI is associated with early timing spermarche and menarche. Boys Girls Girls 1278258 9-15 2005-2012 He et al24 Holmgren et al17 2017 China 2017 Sweden Cross-sectional Longitudinal Onset of puberty is not related to obesity in boys. Boys Boys Girls Girls 782 7-17 972 929 5839 Kelly et al19 2017 UK 2016 Brazil 2016 USA Longitudinal prospective cohort Higher BMI in girls is associated with the onset of menstruation at an earlier age. 11 10-18 11-17 Barcellos Gemelli et al25 Cross-sectional Longitudinal Excess weight is associated with early age of menarche. Girls 727 2014 2003-2009 Glass et al16 Lee et al26 In girls, but not in boys, greater adiposity is associated with the earlier onset of puberty. Boys Girls 135 Cabrera et al27 Leonibus et al14 2014 USA 2013 Italy Cross-sectional Longitudinal Thelarche occurred earlier than recently reported, while age of menarche remained unchanged. Girls 610 3-17.9 2007 2005-2012 Currie et al13 2012 Europe, USA, Canada Cross-sectional Overweight/obesity during childhood predicts the early onset of puberty in girls. Girls 20410 11, 13, 15 2005-2006 2017 USA Prospective birth cohort Overweight/obese status at the age of 7 ye was associated with increased risk of early menarche 788 From birth to menarche occurred Pregnancies 1959-1966 2016 USA Cross-sectional Boys with overweight enter puberty earlier compared with boys with normal weight or obesity, while puberty starts later in boys with obesity compared with boys with normal weight and overweight. Boys 3872 6-16 2005-2010 Overweight during childhood shows a relation with the early onset of puberty in girls. 6535 4259 695 11 15 5.8-12.2 2009/2010 2013/2014 2014-2017 Higher BMI during childhood is associated with early puberty. 2008 and 2009 2000-2002 Obesity during childhood is related to the earlier onset of puberty. Boys Girls 84 123 71 (Continues) 1467789x, 2020, 6, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/obr.13005, Wiley Online Library on [10/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 4 of 10 NIEUWENHUIS ET AL. 3.1 | Fat storage For the initiation of puberty, the timing of stimulation and/or inhibi- tion of different hormones is important, and additionally, a certain amount and distribution of body fat is needed in order to start menar- che, which emphasizes the importance of body fat. From an evolution- ary point of view, body fat increases in mammalian females during puberty onset, and it highlights the need to guarantee a healthy preg- 40 women with anorexia nervosa. particularly body fat localized predominantly on the gluteofemoral fat depots, is profoundly associated with start of menarche, more than nancy, offspring, and maternal survival. fat, sex-hormones, and neuroendocrine alterations can evolve in men- strual dysfunction, for instance, in women with severe obesity or in 41-43 44-46 to gluteofemoral fat depots suggesting that leptin may convey infor- amount of total body fat. mation on body fat distribution to the hypothalamus during puberty. An improper level of body Importantly, body fat distribution, Blood leptin levels are strongly related 45 3.2 | HPG axis The HPG axis is activated by the release of kisspeptin resulting in the release of GnRH from the hypothalamus, and LH and FSH from the pituitary gland. In girls, FSH is involved in the development of the folli- cles in the ovaries, and it promotes the secretion of estrogen. LH stim- ulates the production of androgen hormones and induces ovulation 48 9,47 the release of kisspeptin and neurokinin B, and kisspeptin thereby (Figure 1). The secretion of estrogen has an inhibitory effect on inhibits the GnRH release from the hypothalamus. pattern of GnRH is important for the regulation of the menstrual cycle. This roughly 28-day-cycle comprises several phases, including the follicular phase and luteal phase. During the follicular phase, increasing levels of FSH stimulate the maturation of follicles and the production of estrogen from the ovaries. This in turn inhibits the release of FSH from the pituitary gland. A high level of estrogen will induce the production of LH by the pituitary gland, resulting in ovula- tion. The matured follicle secretes progesterone thereby inhibiting the release of GnRH. When the corpus luteum is demolished, there is less 48 3.3 | Adipokines According to results from studies reported in Table 1, girls with obe- sity enter puberty earlier compared with girls with normal higher leptin concentrations inhibit the intake of food and increases inhibition of GnRH. As a consequence, the cycle will start again. whole process, starting from the activated HPG axis, results in the development of the secondary sex characteristics in girls including 9,47 thelarche and menarche. 13,14,16-23,49-51 weight. these girls might be found in the secretion of adipokines. For instance, leptin is positively associated with the amount of body fat. Generally, energy expenditure. 9,52-54 An explanation for the early onset of puberty in The expression This TABLE 1 (Continued) Authors Year Country Study Design Primary Outcome Sample Sex Size (n) Age (y) Data Collection Herman-Giddens et al28 2012 USA Cross-sectional Observed mean ages of beginning genital and pubic hair growth and early testicular volumes were earlier than in past studies, depending on the characteristic and race/ethnicity. Boys 4131 6-16 2005-2010 Sorensen et al29 Aksglaede et al30 2010 2009 Denmark Denmark Cross-sectional/longitudinal Longitudinal Puberty onset at earlier ages was associated with an increased BMI in boys. Boys 1528 5.8-19.9 1991-1993/2006-2008 1930-1969 Juul et al31 Ribeiro et al32 2007 2006 Denmark Portugal Retrospective cohort Cross-sectional Higher BMI is associated with early voice break. 11-15 10-15 1990-1999 Kaplowitz et al18 Abbreviation: BMI, body mass USA Cross-sectional The early onset of puberty in Caucasian girls is likely related to an increased BMI. 5-12 1992-1993 2001 index. The higher BMI in boys and girls at 7 y of age, the earlier they enter puberty. Boys 21 612 Girls 135 223 Boys 463 Boys 382 Girls 437 Girls 10 750 Early sexual maturation in boys and girls is associated with overweight. 1467789x, 2020, 6, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/obr.13005, Wiley Online Library on [10/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License NIEUWENHUIS ET AL. 5 of 10 Leptin may possibly play a role in adrenarche as its plasma level increases with higher levels of body fat and as it can modulate both girls. 33 ing adrenarche. In coherence, in children with obesity, the androgen These findings suggested that lower reproductive status was associated with higher total adiponectin concentrations and that a higher reproductive status was related to higher HMW adiponectin the HPA and HPG axes. These axes are functionally integrated dur- DHEAS was positively associated with leptin levels. Nevertheless, concentrations in girls. In addition, individuals with obesity often another study showed that enhanced adrenal androgen secretion in girls with premature adrenarche was not explained by leptin or BMI 55 ated with androgen levels in girls ; however, it was not related to levels. and IL-6. TNF-α alters, and IL-6 inhibits the expression of 56 8 In addition, the adipokine adiponectin was negatively associ- 57 differences of adiponectin seem to develop during the progression of 56 adiponectin (Figure 2). Thereby, a low level of total adiponectin and/or high levels of inflammatory cytokines in individuals with obe- sity can promote the onset of puberty. Many more adipokines are secreted by WAT including omentin, 52,65-67 9,36,62,68 adrenarche in girls with Prader-Willi syndrome. Interestingly, sex puberty. adrenarche; however, both are not required factors. Thus, leptin and adiponectin might be able to influence In gonadarche, leptin can stimulate the secretion of kisspeptin, and subsequently activation of the HPG axis, which eventually increases the expression of estrogen and androstenedione in the ova- 58 2,60 65-67 The expression of these ries (Figure 2). Ob gene in WAT, resulting in the synthesis and secretion of leptin. Thus, high levels of leptin promote onset of puberty in girls via secre- tion of kisspeptin, and estrogen stimulates leptin secretion addition- ally. Moreover, adiponectin can affect the HPG axis due to the expression of adiponectin receptors in the hypothalamus, pituitary In return, estrogen stimulates the expression of the 59 gland, and gonads. onset as it inhibits the secretion of kisspeptin and GnRH in the hypo- thalamus and the release of GH and LH in the pituitary gland, and 2,60-62 52,60 63 girls with central precocious puberty (CPP). Moreover, total adiponectin had negative correlations with progression of puberty in girls (defined by Tanner stages), whereas HMW adiponectin had FIGURE 2 Adipokinesaffectingthe initiation of puberty in girls. Leptin stimulates the release of kisspeptin in KNDy neurons, which activates the hypothalamus to produce gonadotropin releasing hormone (GnRH). In response to the release of GnRH, the pituitary gland secretes follicle stimulating hormone (FSH) and luteinising hormone (LH), which stimulates the ovaries to release estrogen resulting in the formation of secondary sex characteristics in girls. Estrogen stimulates the production of leptin. Adiponectin inhibits GnRH release resulting in reduced levels of GnRH and thereby a delayed onset of puberty. TNF- α and IL-6 inhibit the production of adiponectin and therefore stimulate the onset of puberty In detail, adiponectin is a regulator of puberty thereby inhibiting the onset of puberty (Figure 2). with obesity often have low levels of adiponectin. et al. showed that total adiponectin was significantly lower, whereas high molecular weight (HMW) adiponectin was significantly higher in ment. 55 63 develop a chronic low-grade inflammatory state, which can be indi- cated by a high level of circulating inflammatory cytokines like TNF-α 64 Individuals Sitticharoon positive associations with LH levels and the progression of puberty in 63 visfatin, resistin, and chemerin. and visfatin are expressed in the ovaries. adipokines in the ovaries suggests a role within the reproductive sys- tem; however, the exact biological processes have to be examined. Thus, specifically leptin, adiponectin, and inflammatory cytokines pro- duced by WAT could be permissive key players during an early onset of puberty in girls with obesity. As an exception, HMW adiponectin seems to have a stimulatory effect on peripheral repro- ductive function as HMW is not able to cross the blood brain 63 barrier. 4 | Markers that are used to assess puberty onset in boys are THE ONSET OF PUBERTY IN BOYS spermarche, voice break, testicular volume, and pubic hair develop- 35 spermarche develop in the early stages of puberty onset, voice In women, omentin, chemerin, While pubic hair development, larger testicular volume, and 69 testicular volume increases, which occurs at an average age of break usually appears in later stages of puberty. Generally, first 1467789x, 2020, 6, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/obr.13005, Wiley Online Library on [10/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 6 of 10 NIEUWENHUIS ET AL. 11.9 years, followed by the development of pubic hair at 12.2 years of average, and lastly, boys experience spermarche around an aver- 55 related with leptin levels. Thereby, leptin plausibly has a minor impact in adrenarche in boys. Since leptin receptors are found in the hypothalamus, pituitary gland, and testes, they might be involved in the onset of puberty by affecting the HPG axis during gonadarche. Leptin stimulates the release of kisspeptin and GnRH, and as a consequence, it accelerates the onset of puberty (Table 1, Figure 3). In contrast, adiponectin inhibits the secretion of GnRH, GH, LH, and FSH therewith delaying the onset of puberty. However, adiponectin levels are generally lower in men compared with women and even lower in men with obe- age age of 13.4 years. 70 4.1 | Fat storage Many aspects of the reproductive physiology are energetically demanding,71 and therefore, an adequate energy level is necessary. In boys, a dynamic change in body composition occurs around the age of 10 to 13 years, in which they gain approximately 40% of sity. culating inflammatory cytokines. levels can stimulate the HPG axis and therewith an early onset of puberty in boys. Nevertheless, leptin can inhibit the production of tes- 72 mostly consisting of lean mass, which causes exhaustion of most of fat. Subsequently, a growth spurt follows in which they gain tissue 72 in boys, an adequate amount of body fat is important in the onset of their body fat. These alterations in amount of body fat indicate that 4.2 | Puberty in boys is initiated by the release of kisspeptin. As mentioned before, this activates the HPG axis, resulting in the release of GnRH from the hypothalamus, and consequently the release of LH and FSH 9,74 puberty. tosterone from the testes, to estrogen (Figure 3). of the development of secondary sex characteristics in boys. Additionally, leptin can affect fertility in men as it can modulate the nutritional support of spermatogenesis, and moreover, dysfunction of spermatogenesis is associated with an increased leptin level and 73 58 2,60-62 HPG axis from the pituitary gland (Figure 1). and LH stimulates the secretion of testosterone from the testes, which inhibits the release of kisspeptin from the KNDy neurons and 9,48 in men, the release of kisspeptin is more consistent, causing a con- 29,48 subsequently GnRH from the hypothalamus. receptors expressed on KNDy neurons. In humans, KNDy neurons Contrarily to women, LH-induced testosterone levels lead to the stant release of LH. development of secondary sex characteristics in boys. differences between sexes in kisspeptin release are related to a sex- specific and sex steroid-dependent kisspeptin system as estrogen and progesterone modulate kisspeptin activity through the sex-steroid 48 in the infundibular nucleus are involved in negative and positive sex- 48 tal exposure to sex steroids and result in sex-specific differences in steroid feedbacks. kisspeptin release. These sexual dimorphisms are induced by perina- 75,76 4.3 | Adipokines The association between obesity and puberty onset in boys is rather controversial compared with findings in girls. Most studies reported an early onset of puberty in boys associated with increased ate adipose tissue from actual breast tissue. stages are more difficult to assess than female stages as boys lack a more determined marker such as menarche. Thirdly, puberty onset can be indicated by the activation of the HPG axis, and the presence of these secondary sex characteristics is the result of hormonal 2 14,17,22,23,50,51,77,78 BMI, 20,49 all while others reported no associations at Current markers used 79 16,80 or a delayed onset of puberty (Table 1). The presence of excessive adipose tissue can be involved in puberty onset in boys as the secretion of adipokines can modulate both adrenarche and gonadarche. Leptin can affect adrenarche by modulating both the HPG and HPA axes,33 and moreover, androgen levels were positively 55 nal androgen secretion in boys with premature adrenarche was not associated with plasma leptin levels. Nevertheless, enhanced adre- 9 In more detail, 61,62 adiponectin, and individuals with obesity often have high levels of cir- Moreover, inflammatory cytokines, TNF-α, and IL-6, inhibit expression of the leptin receptor in the testis. FSH induces spermatogenesis, too. function and role still have to be examined. 64 High leptin and low adiponectin and fat tissue can convert testosterone Both processes might result in the delay 29,61,79 81,82 In men, other adipokines like chemerin are found in the gonads 65 Thus, particularly high leptin and low adiponectin levels stimulate the HPG axis and thereby accelerate the onset of puberty in boys. Additionally, leptin can dysregulate the development of secondary sex characteristics and spermatogenesis by affecting testosterone levels and nutritional sup- port of spermatogenesis. 5 | LIMITATIONS AND FUTURE RESEARCH DIRECTIONS Even though multiple epidemiological studies have shown the link between puberty onset and obesity, there are some important limita- tions. Firstly, determining both the onset and stage of puberty is rather difficult. For instance, assessing the stage of breast develop- ment in girls with obesity is complicated as clinicians should differenti- 2 changes in response to the activated HPG axis. to determine the onset of puberty refer to secondary sex characteris- tics, such as testicular volume in boys and breast development in girls. A more accurate measurement of puberty onset would be to combine secondary sex characteristics with plasma or serum hormone level measurements such as LH, FSH, adipokines, e.g. leptin. Thereby, differences in puberty measurements could explain variations in the age of puberty onset between boys and girls within different Thereby, resistin is expressed in the testes of rats, but its exact 83 Secondly, male pubertal 1467789x, 2020, 6, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/obr.13005, Wiley Online Library on [10/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License NIEUWENHUIS ET AL. 7 of 10 FIGURE 3 Adipokines affecting the initiation of puberty in boys. Leptin activates kisspeptin secretion in KNDy neurons, this activates the production of gonadotropin releasing hormone (GnRH) from the hypothalamus. GnRH stimulates the pituitary gland to secrete follicle stimulating hormone (FSH) and luteinising hormone (LH), activating the production of testosterone from the testes allowing the development of secondary sex characteristics. Leptin also inhibits the production of testosterone, which may cause a delayed onset of puberty. Adiponectin inhibits GnRH release. Low levels of adiponectin, as a result of TNF-α and IL-6 expression, lead to a reduced inhibition of GnRH. In response to GnRH release, the pituitary gland will secrete FSH and LH, and the testes will produce testosterone resulting in the development of secondary sex characteristics in boys countries, and In addition, the inclusion of a of puberty. ferent time points is complicated, as subjects examined several decades ago presented pronounced differences concerning lifestyle patterns such as nutrition and exercise habits. Lastly, obesity or over- weight is often determined by BMI, a classification based on weight and height measurements. Additionally, it is important that all studies studies or across continents, ethnicities proper age range (8-16 years) is important when assessing the onset (Figure 4). 12-15,17,20-23,49,77-79,84,85 30,47 Furthermore, comparison between studies from dif- 86 Specifically in children, BMI is often dependent on age and growth use the same anthropometric standards and sex-specific cut-offs. 13,14,16-23,49-51,77-80 fat and would represent a more accurate measurement in its regard. Based on this review, several suggestions can be made for further research. Firstly, the roles of adipokines like resistin, chemerin, visfatin, and omentin in puberty onset, fertility, and sexual maturation should be examined in detail. Secondly, future research examining the onset of puberty should combine indicators of puberty onset (e.g. breast development or testicular volume) with plasma or serum hor- mone measurements such as LH, FSH, sex-steroids, adipokines (e.g. spurts. ment in case of growth spurts. distribution of body fat should be taken into account in determining puberty and obesity in children. For instance, the body adiposity index (BAI), which was introduced in 2011 by Bergman et al.,87 uses hip cir- cumference and height in order to estimate the percentage of body 87 Thereby, BMI is a less accurate measure- F I G U R E 4 87,88 Therefore, both percentage and Average age of puberty onset in Europe, China, and the United States according to several studies from Table 1. Age of puberty onset ranges from 8.47 to 13.33 years in girls and from 8.63 leptin), and body fat distribution (e.g. BAI,87 waist-hip ratio's and/or dual-energy X-ray absorptiometry (DXA)2). Additionally, defining con- sistent and general measurements of puberty in both boys and girls, combined with a proper age range (8-16 years), would facilitate the comparisons between different studies and their results. 12-15, 17, 20-23, 25-29, 31 to 13.7 years in boys. included if average age of markers used to assess puberty was not reported. Pink: girls. Blue: boys Studies (Table 1) were not 39, 56 1467789x, 2020, 6, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/obr.13005, Wiley Online Library on [10/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 8 of 10 NIEUWENHUIS ET AL. 6 | CONCLUSION In conclusion, epidemiological data regarding obesity and puberty onset in girls show similar outcomes as adiposity results in the early onset of puberty in girls. The majority of the studies examining boys with obesity indicate an early onset of puberty, while not all reported an earlier onset of puberty. In detail, high leptin, TNF-α, and IL-6 levels combined with low adiponectin levels stimulate the activation of the HPG axis in girls and boys with obesity, and 5, 45, 50, 51 REFERENCES 1. Kumar S, Kelly AS. Review of childhood obesity: from epidemiology, etiology, and comorbidities to clinical assessment and treatment. May- o Clin Proc. 2017;92(2):251-265. 2. Reinehr T, Roth CL. Is there a causal relationship between obesity and puberty? The Lancet Child & adolescent health. 2019;3(1):44-54. 3. WorldHealthOrganization. Facts and figures on childhood obesity. 2017. 4. Guglielmi V, Sbraccia P. Obesity phenotypes: depot-differences in adipose tissue and their clinical implications. Eat Weight Disord. 2018; 23(1):3-14. 5. Gomez-Hernandez A, Beneit N, Diaz-Castroverde S. Escribano O. 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FUNDING INFORMATION This research was funded by Europees Fonds voor Regionale Ontwikkeling (EFRO), project BriteN 2016. ORCID Ilse A.C. Arnoldussen Amanda J. Kiliaan https://orcid.org/0000-0002-7395-5284 https://orcid.org/0000-0002-2158-6210 13, 14, 16-26, 29-32 Furthermore, several receptors Nevertheless, We conclude Search strategy We searched PubMed for articles published before Novem- ber 15th, 2019 using relevant keywords, including âonset of puberty and adiposity/obesityâ, âonset of pubertyâ, âchildren with obesityâ, âadipose tissueâ, âchildhood obesityâ, âadiposityâ, âobesityâ, âadipokine(s)â, âHPG axisâ, âadipokines ovary/ova- riesâ, or âadipokines testesâ, either alone or in combination. 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Obesity Reviews. 2020;21:e13005. https://doi.org/ 10.1111/obr.13005 1467789x, 2020, 6, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/obr.13005, Wiley Online Library on [10/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are gover
Musical Texture Texture Musical texture is the element of music that analyzes musical layers in terms of number and function. The most basic texture is called monophonic. Oh mama, I'm in fear for my life from the long arm of the law. Monophonic texture has only one layer, a melody. With monophony, it doesn't matter how many instruments and or voices are present if they are all singing or playing the same thing at the same time. It also doesn't matter if the voices or instruments are on the exact same frequency, or if they are singing in octaves. An octave is the distance between two musical pitches that sound almost the same, but one is higher and one is lower. It also doesn't matter if drums are present or not. In most cases, drums, the rhythmic layer, are neither melody nor harmony, and therefore are generally not considered when determining texture type. Too much monophony can be boring, so most music has another kind of layer, harmony. When a melody is supported by a harmony, the texture is homophonic. No one may ever know the feelings inside my mind. All the lines I ever write are running out of time. One layer grabs your attention, and the other layer is just hanging out in the background. Most popular music is homophonic. Notice how there was only one instrument in the previous example, a piano, but there were two different things happening on that instrument, a melody, and a harmony. What if a piece of music has multiple independent layers happening at the same time, and you're not sure which one is the melody? This is called polyphony. Polyphony can occur if you take the same melody but start it at staggered intervals. This is called a round. âȘ The last texture is called heterophony. Heterophony is relatively rare in Western music but is very common in non-Western music. It occurs when there are two or more versions of the same melody happening at the same time. Usually, one of the melody lines has more notes than the other, a kind of musical decoration, and or a slightly different rhythmic pattern. Songs will often use a variety of textures to keep the piece interesting. Come on, I need you, I swear, at this moment, you need everything. Come on, I need you, I swear, at this moment, you need everything. Start trying to identify the musical textures in your favorite music.
Gever Tulley is a computer scientist from California. In 2005, he started a summer programme for children called Tinkering School. The idea was that children can learn important skills for life by building things together. Gever Tulley and his team help the children to think big and create plans for innovative things they want to build. Children have made fantastic things since the school started. They have built a rollercoaster. They have made a rope bridge from plastic shopping bags. They have made tree houses, wooden motorbikes and boats. At Tinkering School, children get all kinds of materials like wood, metal, plastic, nails and ropes. They get lots of real tools too, such as knives, hammers, screwdrivers and power drills. Some children have cut themselves when using a knife, or hurt their fingers when using a hammer. Tinkering School has been around for many years now, but nobody has ever suffered a serious injury in all those years. This is because there are strict health and safety regulations they must follow. The children always learn how to use the tools safely and they must wear the right clothing and protection at all times. Gever Tulley's ideas have worked very well. A lot of children have gone to his summer schools over the years. In 2011, Gever Tulley and a colleague decided to create a 'real' ! school, called Brightworks, in San Francisco. The school is very small-it only has 20 students aged 6 to 13. Brightworks is based on the same principles as Tinkering School. Since it started, Brightworks has been written about a lot. Most of those articles have been very positive. They have praised the quality of the school. They have found the children are more motivated than at many other schools. But since the beginning of the school there have also been critical voices. Some people have said that children are not learning enough at Brightworks. They feel that students and teachers are just 'playing around' all the time. The students at Brightworks seem to love their school. We spoke to 12-year-old Tina Cooper. She has been a student at the school since last October. 'Since I started here, I've never sat in a 'normal' class with a teacher,' she told us. 'But it's been a very exciting experience. I've worked hard at my new school for eight months now, and there hasn't been one single moment when I found it boring. Before, I was bored quite often.'