There are countless other such habits, such as hair-pulling, but recreating the familiar is what is common to all 'self-soothing' behaviours. Some behaviours do not actually soothe but instead amplify the distressed feeling, and it is these that deserve special attention by the parents, carers and early years practitioners.
All babies have a need to suck, for nourishment, pleasure and relief from distressing feelings. Quite often the discovery of a finger to suck is extended to a cuddly toy or the end of a blanket, which becomes important to the child at night or in new situations. Thumb-sucking occurs in about half of all infants, and while most stop it by the age of two or three years, some continue on into adulthood.
Thumb-sucking is usually an effective way for babies and young children to soothe themselves when they feel anxious about separations from loved ones, are in a new situation, or simply want to feel cosy in a known situation. Unless thumb-sucking is chronic (as with children sucking their thumbs all day) or lasts past the age of six, there is nothing practitioners need to be concerned about.
When it persists, children may be communicating disappointment with their parents or a feeling of emptiness, and soothing themselves in this way may feel like the only means of obtaining comfort. Thumbsucking also risks a child's mature teeth becoming misaligned - the usual reason that parents nag children to stop. Parents sometimes give their children dummies, but it makes no difference whether a child sucks their thumb or a dummy.
Rhythmic, repetitive movement is another common way that infants and young children soothe themselves. It is thought to mimic the feeling of being held and rocked. More common in infants and young children who have been institutionalised, it often disappears if a baby is placed in an environment where they can move more freely than in a cot, only to reappear in times of stress such as illness.
There is a form of head-banging better referred to as head-knocking in which a baby or toddler gently rocks their head against the soft part of the cot. This deserves mention here for its closeness to rocking, owing to its use of rhythmic motion to calm.
There are some babies and toddlers whose rocking can be fierce, and care needs to be taken that they cannot injure themselves in their cots. In very rare cases, rocking may occur due to epilepsy and should not be confused with an expression of emotion. If rocking persists in older children and epilepsy has been ruled out, this is likely to indicate feelings of loneliness.
It is normal and expected for all young children to explore everything about their bodies, and children are always particularly curious about genitals and any place with an opening - the nose, mouth, anus and genitals. When children discover the nice sensations arising from touching their genitals, there is no reason to stop them, though they need to know that it is something to do privately.
It is not uncommon, particularly for young boys, to want to hold their penis, particularly in new situations, to overcome anxiety caused from making the transition from an earlier, familiar experience. The only reason for any kind of concern is if a child is unable to stop touching himself in public, even after gentle encouraging to do so privately.
Such cases can signal many things and require a sensitive adult to help find out more about the meaning. For some, chronic masturbation may signal feeling excessively alone and abandoned. For other young children, chronic masturbation may signify overstimulation of the region being stroked, and the excessive touching communicates the children's worry about this part of their body.
Just as there are many different types of thumb-suckers, there are different sorts of head-bangers. Some babies and toddlers gently knock their heads against a soft part of their cots to lull themselves to sleep, and this does not involve pain. Others bang their heads against a hard part of their cot, walls or other hard surfaces to communicate their extreme frustration and hopeless rage.
It has been observed that the frustration and anger usually precede the act of head-banging. For example, the children will cry out in frustration or anger, and when not soothed, begin to bang their heads.
Head-banging differs from the above modes of self-soothing in that the infants cause themselves pain in response to a frustrating feeling. Though there are numerous kinds of head-bangers, and it is reported that some do so because of being active and physical, it is our experience that infants who head-bang are communicating a painful dynamic in the relationship to the mother or carer.
Calming thumb-sucking probably repeats the soothing experience of breastfeeding or bottle-feeding with the mother, and in the same way, head-banging repeats the overload of frustration or pain that the child feels. Most infants cease head-banging by the age of two, though this habit is often woven into a toddler's tantrums, or evolves into self-harming behaviours.
Some nail-biters are doing nothing short of thumb-sucking with a bit of chewing. When done gently, it is an effective means for self-soothing with the added benefit of taking something (the nail) inside when it feels as if something is missing, or there's not enough emotional fuel. At the other end of the spectrum, there is fierce nail-biting, leading to bleeding, or worse, the entire nail bed being dislodged.
With the exception of the soothing kind, nail-biting is a more aggressive behaviour indicative of frustration and impotent anger and is often done to diffuse tension. Nail-biting is extremely common, existing in between one third and one half of all young children, and half of all adolescents.
Children usually begin to bite their nails in the face of loss and change, such as the arrival of a new baby. It is assumed that the biting expresses the anger or frustration of loss (the child knows they can do nothing to change the situation), while the ingesting of the nail expresses the wish to take something inside that has been lost.
Impervious to parental nagging, nail-biters sometimes drop the habit when feeling more fulfilled and calm, or when they, mostly girls, want to have prettier hands. Since the term 'nail-biting' is synonymous with anxious waiting, it could be surmised that nail-biters are anxiously waiting without an expectation of being soothed at that particular moment.
It is known that nail-biting increases when anxiety increases. Nail-biting is not effective at soothing the child, but if sensitive adults can help make links between the behaviour and the underlying feeling without sounding judgmental, young children can begin to notice how their nail-biting signals that they are worried. Once that link is made, the child can begin to address the worries with a parent or teacher.
When nail-biting is compulsive, leading to a lot of pain or bleeding, children are expressing how overwhelmed (literally devoured) they feel by their worries. Emotional 'feeding' can go a long way towards quelling such anxieties. Though it may not end the nail-biting, children who feel emotionally fed and nourished will not need to continue to devour a part of themselves in this way, until the next time they feel overwhelmed by anxiety.
HOW TO RESPOND
In considering how best to help a child whose habits are expressing distress, it is a fine line that parents and practitioners walk between nagging and being genuinely helpful. Parents often feel persecuted by their child's habits, and nagging is their own impulsive habituated manner of dealing with their feelings about their child's habit. Parental concern can often come over to the child as nagging or a demand that they stop feeling the way that they are feeling.
Conveying authentic empathy with the underlying emotion always works best. This is usually easier said than done, particularly when parents feel that they are to blame for their child's anxious habit. If a child's behaviours are causing trauma or harm (if head-banging is causing bruising, for example), the parents should consult a child psychotherapist or their health visitor.
This article is based on a Nursery World 'Behaviour' series by psychologists at the Anna Freud Centre in north London, a registered charity, offering treatment, training and research into emotional development in childhood