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In their book Raising a Sensory Smart Child, Lindsey Biel and Nancy Peske describe taste and smell as ‘The yum and yuck of it all’ – which, in the simplest of terms, describes the defensive and discriminative aspects of these senses from a child’s perspective.
Both taste and smell have been fundamental to our survival since primitive times when something ‘yucky’ was probably bad for us (for example, poisonous, over-ripe, decayed), and if it was ‘yum’ that encouraged us to eat it, because we needed the protein, minerals and vitamins it contained in order to survive.
It isn’t quite as simple as that any more, sadly, as our tastes have become habituated to things that aren’t always good for us – at least not in large quantities (such as sugar, salt and additives), but our olfactory (smell) and gustatory (taste) senses are still very important to the quality of our lives – and our survival.
All our senses are interconnected, but there is a very strong connection between these two. That’s why food seems to lose flavour when we have a heavy head cold. It’s not your taste buds that have been affected but your olfactory sense that can’t work so well when your nose is stuffed up. We need the two senses working together to really appreciate and discriminate food and other taste experiences.
SMELL AND TASTE
Odour molecules travel in the air to the smell receptors in your nose, sending impulses directly into the limbic system in the brain – the centre for emotions, pleasure and memory. This is why our sense of smell can bring back really strong memories and feelings and why we tend to notice more those smells that produce some sort of an emotional response or connection, even though our sense of smell is working all the time. So, if it’s a horrible smell we wrinkle our nose and pull a face, and if it’s nice we might sniff harder to get a stronger experience of it. There are lots of odours that will have a similar effect on most people, but our olfactory sense is also highly individualised, linked both to our experiences and our levels of sensitivity to scents and smells (Phelan – see References and further reading).
We can detect several thousand smells, but there are actually just five basic, primary flavours – salty, sweet, sour, bitter and umami (a savoury taste triggered by protein). Texture and temperature are also important when we taste things but are actually our tactile sense at work. Saliva is also important in helping us taste (and digest) – that is why our mouths water when we anticipate food.
HEALTHY DEVELOPMENT
Just like the other senses, taste and smell develop gradually and developmentally through human connection and playful experience, as children’s bodies mature and their ability to engage with the world around them increases. Babies respond almost immediately to both the smell and taste of milk and the skin of their primary carers – and are keen to explore the world up close with both their noses and their mouths! This instinctive urge to ‘mouth’ everything is key to the early development of taste and smell (as well as touch) as there are more sensory receptors in the mouth than anywhere else on a baby’s body.
As they become mobile and there is more of the world to explore, they not only learn what smells and tastes nice or nasty (defensive) but the brain is also starting to make sense of what is ‘food’ and what is something else (discriminative). The emotional impact of these two senses is clear as babies quickly learn to associate the smell of milk, certain foods and important people with comfort and security.
For many children, the taste and smell of a comfort blanket or cuddly toy is also hugely important, particularly as they take brave steps into the world trying new experiences. This is why they can be very sensitive to the unfamiliar smell of a teddy bear who has been washed and dried! The opportunity to play freely alongside others, indoors and outdoors and in both the natural and manufactured world is, therefore, the biggest agent to healthy development of taste and smell.
HEALTH WARNINGS
Alongside this natural urge for sensory exploration, we must also be sure to give developmentally appropriate warnings about things in our environment that are dangerous when sniffed, tasted or swallowed. Learning from an early age to associate chemicals and certain plants with danger if ingested is as important as learning that fire can be dangerous if misused.
Although we tend to be very vigilant about poisonous things that can be swallowed, we also need to remind children that fumes and gases from everyday things can also be extremely poisonous when breathed in or inhaled. This can make a big difference later if children find themselves exposed to peer pressure to experiment with inhalants or other drugs, as an instinctive association with danger can help outweigh curiosity.
Tasting and sniffing activities should always be well supervised and with reminders to young children that they should only taste or sniff things that a trusted grown-up has offered them.
PROBLEMS WITH PROCESSING SMELL AND TASTE
Healthy development of our olfactory system not only helps us to discriminate different smells, it also allows us to filter out those we can safely ignore. Pretty much everything in our environment comes with a smell, and it would be exhausting if our brains paid attention to them all. Which is why being over-sensitive to smell or taste can make some children very anxious.
Some smells and tastes will seem much more intense to them and they are likely to have broader and more extreme reactions and associations with them. On the other hand, children whose olfactory and gustatory systems are under-responsive may constantly seek out smells and tastes (to get the extra input their brain knows it needs) and this can interfere with daily life or what is considered normal behaviour (Phelan – see References and further reading).
Red flags
There are a range of problems that can occur with olfactory and gustatory processing, some of which may be linked to other conditions or learning disorders such as autism – but not exclusively. Remember that healthy development of the senses is developmental and unique to the individual, but as with all sensory development there are certain ‘red flags’.
Olfactory ‘red flags’
Red flags that might indicate issues with olfactory processing include:
- very strong reactions to smells that others don’t even notice
- resistance to being around certain odours – this can include people, as well as places and things
- strong reactions to some foods.
- Alternatively, children might:
- have a very strong urge to sniff things, both natural (such as plants, people and wood) or manufactured (such as soap, marker pens, petrol and other chemicals)
- seem not to notice bad smells or changes in smell.
Gustatory ‘red flags’
Children with gustatory processing issues might:
- react very strongly to tastes, or changes in taste, that others might not notice
- object to the textures and feel of food in their mouth
- have a limited range of tolerated foods
- have strong reactions to non-foodstuffs such as toothpaste or medicine
- really dislike brushing their teeth or going to the dentist.
Alternatively, they might:
- often mouth, chew or lick non-edible things, e.g. their clothes, toys, etc. past the age where this is usual
- like food and drinks very hot / cold or with strong flavours or heavily seasoned
- enjoy vibrating toothbrushes, strong toothpaste.
Issues with eating
All the above, inevitably, can have an impact on a child’s enjoyment of food and ease with eating. Feeling anxious around smells and tastes can make mealtimes very uncomfortable for the child and frustrating for parents and carers. The ‘threat’ of certain foods can feel very real to a child, however, and no inducement (bribes or sanctions) will reduce the anxiety.
Many of us perhaps have sad stories of having to ‘sit there until you’ve eaten it’ while our parents worried about our ‘picky eating’ or ‘food fads’. If you were the child who could always eat ‘everything put in front of you’ and were rewarded for being a good eater, it might be difficult to appreciate the level of fear that some children (and even adults) experience around food.
‘Picky eating’ is rarely about manipulation, but it is a behaviour through which a child is trying to communicate how they feel. Remember, eating is actually quite a complicated multi-sensory experience for children, and tuning into children with kindness and compassion is just as important at mealtimes as it is during any other learning experience.
It’s also worth remembering that telling children to clear their plates and forcing them to eat food they don’t like has been linked to obesity in later life, as it reduces a child’s ability to appreciate taste and to read their own bodily cues about when they have had enough. For some good ideas on helping children with food sensitivity issues, see www.pocketot.com/5-tips-for-picky-eaters.
SUPPORTING OLFACTORY AND GUSTATORY DEVELOPMENT AT SEND TO LEARN NURSERY
Although these senses are often linked, at SEND to Learn we have had more children with taste sensitivities than olfactory issues. We take a desensitisation approach, where the child is gradually introduced to either the taste or the smell, or in some cases both.
We have a lot of food in the setting and initially all the child who has sensory issues has to do is to go and look to see what is on offer in that area. In the food tray, there will be utensils for the child to use before they are expected to touch the food.
In one case a child was introduced to foods such as baked beans and spaghetti first by coming to have a look, then by playing with the utensils, then with his hands. He was then encouraged to put his finger onto his lips, then lick his finger, and the same procedure was repeated with a baked bean until eventually the food went into his mouth. By the end of two terms, the child was eating cold baked beans and spaghetti and really liked them! It was a long, slow process but worth it in the end as we had opened up his choice of foods. This has been repeated various times with a wide range of food.
At mealtimes we will initially place a piece of ‘unliked’ food next to the child’s plate. Once the child is accepting of this, the item of food will be placed onto the plate (sometimes we use a segmented plate). The child will then be encouraged to touch the food even if it is just to remove it from the plate. Then we encourage them to touch the food to their lip, then lick it, then put it in their mouth and take it out – and finally put the food in their mouth and eat it.
Snacks and stories
Selections of snack food may be placed out on the table during snack times and children will be encouraged to try them all. This takes a long time and should be taken at the child’s lead. We run a number of feeding programmes with children to help encourage their range of food intake, and these are supervised by the child’s dietitian, and food diaries are kept.
Favourite stories can be used to introduce new food, such as The Very Hungry Caterpillar, Handa’s Surprise, Max’s Sandwich Book and Oliver’s Fruit Salad (there are many more), where children are given the opportunity to taste the food that is in the story. Work on celebrations can involve food, or even a food theme in nursery will help with desensitisation.
Pica
Care has to be taken if children are tasting, mouthing or eating non-food items as this may be potentially dangerous. Nursery gardens and play areas need to be checked in relation to poisonous plants and substances (lists can be found via an internet search). If the child is over the age when they would be developmentally mouthing lots of different things (that is, over two years approximately), this may be due to a condition known as ‘pica’. This is an eating disorder that involves eating items that are not typically thought of as food and that do not contain significant nutritional value. See www.nationaleatingdisorders.org/learn/by-eating-disorder/other/pica for more information and seek specialist support if you are concerned about a child’s abnormal eating urges.
Olfactory desensitisation
In relation to olfactory desensitisation, we use ‘smelling pots’ where items are placed in pots with small holes in the top so that the child can smell the contents. Fabrics impregnated with certain smells can also be used alongside perfumes being sprayed onto staff hands so that the child can smell these.
For those children who are under-sensitive to smell, smelling pots and sensory play with strong-smelling items can work well. We currently have a little one who comes into nursery with a small piece of fabric which has vanilla essence placed on it, and he carries this around with him. We have also explored cat and dog food due to their more pungent smell. (Please note the guidance above about smelling and tasting activities.)
We have had children who have been sensitive to the smells of places when we have been out and about and we try to recreate that smell in nursery through cooking the same food, so that the child can smell the food coming from the kitchen – but we can shut it out by moving to another room. This can be done with other items, but remember to have an option of removing the smell or the child from the area so as not to cause distress. An alternative approach can be taken when out and about where the child takes a piece of fabric impregnated with a smell of preference so they can smell this to help block out the unwanted smell.
WHERE TO BUY PRODUCTS
Suppliers that offer a range of tactile resources include:
SpaceKraft https://bit.ly/2WCzuOS
SensoryPlus https://bit.ly/2UsyMpY
Early Years Resources https://bit.ly/2JZeKiL
Learning Resources https://amzn.to/2Iaxb1B
Sensory Education https://bit.ly/2YMXW1S
Rhino Sensory UK https://bit.ly/2OIMTCd
Explore Your Senses https://bit.ly/2YL9AKQ
REFERENCES AND FURTHER READING
Shannon Phelan https://bit.ly/2wMsbt4 and https://bit.ly/2IFGqWl
The Out-of-Sync Child by Carol Stock Kranowitz
Raising a Sensory Smart Child by Biel and Peske
Sensory Integration and the Child by A Jean Ayres
A Moving Child is a Learning Childby Gill Connell and Cheryl McCarthy
Understanding Physical Development: Linking bodies and brains by Anne O’Connor and Anna Daly
NB: Clinical assessments of sensory processing issues must be carried out by an appropriately qualified occupational therapist. Always seek advice and guidance if you are concerned about a child.
About this series
Our five external senses (touch, sight, hearing, smell and taste) and three internal senses (interoceptive, vestibular and proprioceptive) are constantly sending messages to our brains – a process that we often barely register. Yet this sensory information is vital in helping us understand and make sense of the world.
Typical sensory development occurs naturally in childhood. However, for some children this doesn’t happen, causing sensory processing difficulties that impair development and are manifested in children’s behaviour.
Advice and support
Part one of this series provides an introduction to typical and atypical sensory processing and integration. The rest of the series looks at the senses individually, explaining the causes, symptoms and effects of sensory problems and giving advice on how to adapt provision and practice to address a child’s sensory difficulties.
Series authors
Anne O’Connor is an early years consultant and author, specialising in the Prime areas of development (www.primedforlife.co.uk).
Dr Kath Dickinson is owner of SEND to Learn Nursery in Blyth, Northumberland. She has a doctorate in SEND (autism).