Jennifer L. Hammond

EXPERIMENTAL ANALYSIS OF PRECURSORS TO SEVERE PROBLEM BEHAVIOR

Some individuals engage in both mild and severe forms of problem behavior. Research has shown that when mild behaviors precede severe behaviors (i.e., the mild behaviors serve as precursors), they can (a) be maintained by the same source of reinforcement as severe behavior and (b) reduce rates of severe behavior observed during assessment. In Study 1, we developed an objective checklist to identify precursors via videotaped trials for 16 subjects who engaged in problem behavior and identified at least 1 precursor for every subject. In Study 2, we conducted separate functional analyses of precursor and severe problem behaviors for 8 subjects, and obtained correspondence between outcomes in 7 cases. In Study 3, we evaluated noncontingent reinforcement schedule thinning plus differential reinforcement of alternative behavior to reduce precursors, increase appropriate behavior, and maintain low rates of severe behavior during 3 treatment analyses for 2 subjects. Results showed that this treatment strategy was effective for behaviors maintained by positive and negative reinforcement.

Antecedent versus Consequent Events as Predictors of Problem Behavior.

Comparisons of results from descriptive and functional analyses of problem behavior generally have shown poor correspondence. Most descriptive analyses have focused on relations between consequent events and behavior, and it has been noted that attention is a common consequence for problem behavior even though it may not be a functional reinforcer. Because attention may be prescribed simply as a means of stopping serious problem behavior, it is possible that naturally occurring antecedent events (establishing operations) might be better predictors of problem behavior than consequences. We conducted descriptive and functional analyses of the problem behaviors of 7 participants. Conditional probabilities based on combined antecedent and consequent events showed correspondence with the functional analysis data for 4 of the 7 participants, but antecedent events were no better than consequent events in identifying the function of problem behavior.

EFFECTS OF FIXED VERSUS RANDOM CONDITION SEQUENCING DURING MULTIELEMENT FUNCTIONAL ANALYSES

It has been suggested that a fixed condition sequence might facilitate differential responding during multielement functional analyses (FAs) by capitalizing on or limiting sequence effects (Iwata, Pace, et al., 1994); however, the effects of condition sequence have not been examined empirically. We conducted fixed- and random-sequence FAs for 7 individuals with developmental disabilities to determine the relative effects that sequence may have on assessment outcomes. Experimental conditions during the fixed sequence were conducted in the following order: ignore, attention, play, and demand; condition order during the random sequence was determined randomly. Results showed that sequence had no influence on the FA outcomes for 3 subjects, whereas differential responding emerged either faster (1 subject) or only (3 subjects) under the fixed sequence for the remaining subjects. These results suggest that the fixed sequence, a simple modification, should be used when conducting multielement FAs to accommodate the influence of establishing operations across assessment conditions.

Neural correlates of self-injurious behavior in Prader–Willi syndrome

Individuals with Prader–Willi syndrome (PWS), a genetic disorder caused by mutations to the q11‐13 region on chromosome 15, commonly show severe skin‐picking behaviors that can cause open wounds and sores on the body. To our knowledge, however, no studies have examined the potential neural mechanisms underlying these behaviors. Seventeen individuals with PWS, aged 6–25 years, who showed severe skin‐picking behaviors, were recruited and scanned on a 3T scanner. We used functional magnetic resonance imaging (fMRI) while episodes of skin picking were recorded on an MRI‐safe video camera. Three participants displayed skin picking continuously throughout the scan, three participants did not display skin picking, and the data for one participant evidenced significant B0 inhomogeneity that could not be corrected. The data for the remaining 10 participants (six male, four female) who displayed a sufficient number of picking and nonpicking episodes were subjected to fMRI analysis. Results showed that regions involved in interoceptive, motor, attention, and somatosensory processing were activated during episodes of skin‐picking behavior compared with nonpicking episodes. Scores obtained on the Self‐Injury Trauma scale were significantly negatively correlated with mean activation within the right insula and left precentral gyrus. These data indicate that itch and pain processes appear to underlie skin‐picking behaviors in PWS, suggesting that interoceptive disturbance may contribute to the severity and maintenance of abnormal skin‐picking behaviors in PWS. Implications for treatments are discussed. Hum Brain Mapp 36:4135–4143, 2015.

Functional analysis and treatment of aggressive behavior following resection of a craniopharyngioma

Craniopharyngioma is a relatively rare, benign tumor that most often affects pre‐adolescent children. Surgical resection is a common form of treatment, which may result in adverse physical, neurological, and behavioral effects, most notably, aggressive behavior. In this case study we describe a typically developing 6 year old female who had resection of a craniopharyngioma and subsequently developed severe aggressive behavior that interfered significantly with her recovery and functioning. Results of a functional analysis indicated that her aggression was maintained by contingent escape from task demands and access to preferred food items. A highly structured behavioral intervention, consisting of differential reinforcement of alternative behaviors, together with extinction targeted to each function of the behavior, was effective in reducing her aggression to below 88% of baseline levels. Her adaptive behaviors also increased significantly. These results suggest that assessment and treatment utilizing principles of applied behavior analysis can ameliorate the occurrence of problem behavior following craniopharyngioma resection.

An analysis of the topography, severity, potential sources of reinforcement, and treatments utilized for skin picking in Prader-Willi syndrome.

We examined the topography, severity, potential sources of reinforcement, and treatments utilized for skin-picking behavior shown by individuals with Prader-Willi syndrome (PWS). The parents of 55 individuals with PWS, aged 6-25 years, were interviewed about their childs skin-picking behavior using the Self-Injury Trauma Scale (SIT; Iwata, Pace, Kissel, Nau, & Farber, 1990) and the Functional Analysis Screening Tool (FAST; Iwata, DeLeon, & Roscoe, 2013). Results showed that skin picking in PWS occurred on the extremities (i.e., arms, legs, hands, and feet) for 75% of cases and resulted in bodily injury for 83.7% cases. Skin picking posed a high risk to the individual concerned in 41.8% of cases. Automatic sensory stimulation was identified as a potential source of reinforcement in the majority of cases (52.7%) followed by access to social attention or preferred items (36.4%). Treatments utilized by parents were primarily behavioral strategies (56.3%) followed by basic first aid (54.5%). There were no differences in the topography, severity or potential source of reinforcement between those with the deletion (DEL) subtype and those with the uniparental disomy (UPD) subtype. Taken together, these data indicate that skin picking shown by individuals with PWS is a particularly severe and intractable behavioral issue that may be maintained by (as yet unknown) sensory consequences. Further studies to identify the determinants of skin picking in PWS are therefore needed. The implications for interventions are discussed.

Experimental functional analysis of severe skin-picking behavior in Prader–Willi syndrome

Skin picking is an extremely distressing and treatment resistant behavior commonly shown by individuals with Prader-Willi syndrome (PWS). However, with the exception of a limited number of published single-case and survey studies, little is known about the environmental determinants of skin picking in this population. In this study, functional analyses were conducted with thirteen individuals with PWS, aged 6-23 years, who engaged in severe skin-picking behavior. In addition to the conditions typically employed in a functional analysis (i.e., alone, attention, play, demand), we included an ignore condition to examine potential effects of stimulus control by the presence of an adult. Twelve participants engaged in skin picking during the functional analysis, with the highest levels occurring in the alone and ignore conditions for eight participants, suggesting that skin picking in these participants was maintained by automatic reinforcement. For the remaining four participants, an undifferentiated pattern of low-rate skin picking was observed across conditions. These data confirm previous studies indicating that skin picking in PWS may be maintained most often by automatically produced sensory consequences. There were no associations between demographic characteristics of the participants (e.g., sex, age, IQ or BMI) and levels of skin picking observed in the functional analysis. Additional investigations are needed to identify the nature of the sensory consequences produced during episodes of skin picking in PWS. Behavioral interventions designed to extinguish or compete with the potential sensory consequences arising from skin picking in PWS are also warranted.

Examining the Relationship Between Heart Rate and Problem Behavior: A Case Study of Severe Skin Picking in Prader-Willi Syndrome

Few studies have examined the relationship between heart rate and self-injurious behavior (SIB) shown by individuals with IDD (intellectual and developmental disabilities). In this single-case study, we simultaneously monitored heart rate and activity levels during a functional analysis of severe skin picking behavior exhibited by a young man with Prader-Willi syndrome (PWS). Results of the functional analysis indicated that the participants skin picking was maintained by automatic reinforcement. A within-session analysis of the data indicated that skin picking bouts resulted in an increase in heart rate, suggesting a positive- automatic reinforcement function. These data indicate that inclusion of heart rate and activity-level monitoring during a functional analysis may provide important additional information concerning the determinants of SIB.