The Reliability and Stability of Individual Differences in Infant-Mother Attachment

terms of an underlying causal or dispositional trait. Some infants are said to be strongly attached to an adult; others to be less strongly or not at all attached (e.g., Feldman & Ingham 1975) . Attachment is often operationalized in terms of a small number of "attachment behaviors." These include behaviors which promote proximity to presumed attachment figures and behaviors which are perhaps directed more often toward attachment figures than toward nonattachment figures. To operationalize attachment in terms of attachment behaviors is to say that approaching, touching, looking, clinging, protesting separation, etc., are valid "indices" or measures of attachment. Strong attachments have often been inferred from (as well as used to explain) Performance of attachment behavior at high frequency and/or intensity. Trait models assume that various attachment indices are significantly correlated and that individual differences in these behaviors are stable across time.