At a certain point in the normal course of interpersonal development, most children form strong attachments to specific caregivers who take care of them. They develop a clear preference for being with and interacting with those specific caregivers over lesser-known individuals. In cases of Reactive Attachment Disorder of Infancy or Early Childhood (hereafter called Reactive Attachment Disorder), however, the normal attachment process does not occur. Instead, such children develop abnormal relationships with caregivers that are described, in the language of the DSM criteria for the disorder as either Inhibited or Disinhibited.
Children with Reactive Attachment Disorder of the Inhibited type remain unresponsive and ambivalent towards their caregivers. In contrast, children with Reactive Attachment Disorder of the Disinhibited type respond to caregivers, but fail to discriminate them as special people and show a similar level of responsiveness to strangers.
Inhibited type children don't seek out contact with their caregivers, and generally won't respond to caregivers' attempts at making contact either. Such children may come across as apathetic on occasion, but more frequently they appear to simultaneously want and reject the possibility of social comfort. Such children may be guarded, distant, and withdrawn when around caregivers. They may ignore a caregiver's attempts to engage them in conversation, regarding the situation as a threat to be warded off rather than as something safe to engage in. Inhibited type children may actively push away caregivers' attempts to give them hugs or even act aggressively. Instead of seeking comfort from caregivers (which is typical), such children may instead engage in self-soothing behaviors (rocking back and forth or engaging in other forms of self-stimulation)
Disinhibited type children seek out and accept are indiscriminant and may not show a preference for social contact with caregivers vs. relative strangers. These children may act as though they are familiar with strangers, seeking to hug, touch, or otherwise obtain comfort or assistance from them. The interpersonal behavior of Disinhibited type children may remain excessively childish and dependent (younger than appropriate to their years). They may also appear chronically anxious.
Both Inhibited and Disinhibited type children's lack of normal attachment to caregivers is very different than the interpersonal attachment behavior characteristic of Separation Anxiety Disorder where children form an exaggeratedly intense but otherwise normal preferential attachment to particular caregivers.
Disturbances in normal attachment do not happen without reason. The disturbed attachments characteristic of Reactive Attachment Disorder occur as a consequence of what the DSM terms "grossly pathological care" which ultimately fails to meet children's early emotional and physical needs. In other words, Reactive Attachment Disorder is a consequence of neglectful or abusive early parenting which may happen for a variety of reasons, including incapacitated (e.g., drug addicted) or clueless parents; early institutionalization; or serial foster care environments, to name but a few. Not all children who were neglected develop Reactive Attachment disorder. Instead, some children appear to be more vulnerable to the effects of neglect than others who are more resilient. In other words, abusive caregiving is a necessary precursor of Reactive Attachment Disorder, but it is not sufficient in of itself to create the disorder.
Reactive Attachment Disorder is uncommon; however, information on prevalence rates is limited. Because the diagnostic criteria are somewhat nonspecific, the diagnosis for Reactive Attachment Disorder may be given to children who come from a wide range of backgrounds (e.g., children who are institutionalized, children who were maltreated as toddlers and then placed in a series of foster care placements, or children who were once maltreated and now live in stable, loving homes). As a group, children who have been adopted are at elevated risk for the condition because of the increased possibility that they suffered early neglect or abuse, and the variable quality of institutional child care they may have experienced prior to adoption.
DSM criteria require that Reactive Attachment Disorder be first diagnosed prior to a child's 5th birthday. Once established, however, the disorder can persist for years in the absence of appropriate intervention. The early timing and pervasive effect of the disorder means that it can influence and interfere with subsequent interpersonal relationships, such as the development of normal peer and ultimately romantic relationships in later childhood.