Theories of fear acquisition: The development of needle phobia in children

Fear is a normal emotional response to a perceived threatening stimulus, and is a common feature of early development. Developmental fears, including fear of the dark, strangers, and loud noises, are typically transitory and usually resolve in childhood (Mineka & Öhman, 2002). In some cases however, intense fear of certain situations or objects may continue throughout adolescence and remain problematic into adulthood. When fear becomes excessive beyond that which is justified by external threat and markedly interferes with the individual’s ability to function optimally, these fears may then meet criteria for an anxiety spectrum disorder such as Specific Phobia in the Diagnostic and Statistical Manual of Mental Disorders (DSMIV, 2000; see also Barlow & Durand, 2005). Needle phobia is categorized under Specific Phobia bloodinjection-injury subtype in DSM-IV, a cluster of phobias that also includes fear of blood, injury, or any invasive medical procedure. Blood-injectioninjury phobia has been linked to serious consequences including refusal of insulin injections for diabetes, and avoidance of life-saving surgery for cancer (Marks, 1988). Epidemiological studies have reported that identifiable needle phobia has a median age of onset at 5.5 years (Bienvenu & Eaton, 1998) and remains quite common in adulthood (Nir et al., 2003). For instance, in a sample of young adult travellers attending a vaccination clinic, 21.7% reported that they were afraid of injections and 8.2% described their fear as excessive (Nir et al., 2003). In an early epidemiological study, fear of blood and injury was found to be present in approximately one-third of children 6 to 12 years old (Lapouse & Monk, 1959). However, epidemiological studies on bloodinjection-injury phobia have been hampered by a lack of precise definition for the disorder. The most recent prevalence rate based on the DSM-IV criteria for blood-injection-injury phobia indicates that this disorder is present in approximately 3% in the adult population (Bienvenu & Eaton, 1998). This commentary provides a critical overview of proposed pathways for fear acquisition, with particular emphasis on the etiology of needle phobia. The pathways of fear acquisition will be considered within two broad frameworks: (1) the environmental learning pathways (e.g. direct conditioning, vicarious learning, and negative information), and (2) the non-associative pathways (e.g. biological preparedness, genetic mechanisms). The literature has been drawn from work in both pediatric and adult samples because studies focusing principally on needle fear in children are limited. Therefore, etiological inferences had to be drawn from studies on general fear and other specific fear (e.g. fear of spiders) in children and adults.