The premack principle, response deprivation, and establishing operations.

This paper describes response deprivation as an establishing operation. In this context, we review the concept of establishing operation, in particular, its reinforcer-establishing and evocative effects; we place response deprivation in the literature on the reinforcing effects of behavioral activity, wherein response deprivation subsumes the Premack principle; we describe the reinforcer-altering and evocative effects of response deprivation; and we address a methodological concern about the evocative effect. In closing, we discuss some conceptual and empirical implications of the foregoing analyses.

Effects of deprivation on engagement in preferred activities by persons with developmental disabilities.

This study examined the effects of deprivation on engagement in activities for 3 adult men with developmental disabilities. First, an assessment was conducted to identify a high- and a low-preference activity for each participant. Second, the high-preference activity was made available following three amounts of deprivation of the activity (15 min, 2 hr, and 1 to 4 days); the low-preference activity was made available following the schedule of deprivation that produced the highest level of engagement by each participant in the high-preference activity. The results were that 1 to 4 days of deprivation produced the highest average amounts of engagement in the high-preference activity for each participant; this amount of deprivation did not produce high engagement in the low-preference activities. Third, the deprivation procedures and results were replicated when high-preference activities were presented by teachers during the participants' daily activities when their engagement had been quite low.

Monoclonal antibody MT2 identifies the urodele alpha 1 chain of type XII collagen, a developmentally regulated extracellular matrix protein in regenerating newt limbs.

We previously described the upregulation of the MT2 antigen during urodele limb regeneration and characterized the MT2 antigen as a 310- to 325-kDa chondroitin-sulfated glycoprotein with a core protein of 285-300 kDa. In this study, we screened a newt blastema cDNA library using monoclonal antibody (mAb) MT2 and obtained a 1-kb cDNA fragment, designated Isolate (IS)-1. Subsequent screening of the same library using IS-1 cDNA as a probe provided IS-2, a 2.8-kb cDNA. IS-2 overlaps IS-1 at its 5' end, is highly homologous to a portion of the alpha 1 chain of the chicken type XII collagen cDNA (alpha 1[XII]), and spans a third of the chicken alpha 1[XII] cDNA, from the last 62 amino acids of the second A domain of von Willebrand factor to the first two repeats of the fourth fibronectin type III domain. The peptide sequence deduced from cDNA IS-2 demonstrates invariable tryptophan, leucine, threonine, and tyrosine residues that are highly conserved among all the fibronectin type III domains within IS-2 and between corresponding sequences of IS-2 and chicken alpha 1[XII]. A Northern blot showed a 10-kb band that corresponds to the size of the chicken alpha 1[XII] mRNA. A fusion gene was constructed by inserting the IS-2 cDNA downstream from the malE gene of Escherichia coli, which encodes maltose-binding protein (MBP). The isopropyl beta-D-thiogalactoside-induced fusion protein had the expected molecular weight and reacted to both mAb MT2 and rabbit anti-MBP serum. We conclude that mAb MT2 identifies the urodele alpha 1[XII]. The expression pattern of the type XII collagen gene in newt limb regenerates was examined by in situ hybridization. Type XII collagen transcripts first appeared at 3 days after amputation in cells of the basal layer of the wound epithelium. At Day 10, both the basal wound epithelial cells and the distal mesenchyme cells were highly transcriptionally active. At mid-bud and late-bud blastema stages, wound epithelium expression had decreased, whereas the mesenchyme remained strongly active in transcription and showed a tendency toward distal regionalization. Condensing cartilage showed no signal. Finally, at the late digit stage, hybridization became largely restricted to the perichondrium. The in situ results suggest a developmental role for type XII collagen in regeneration.

Monoclonal antibody MT2 identifies an extracellular matrix glycoprotein that is co-localized with tenascin during adult newt limb regeneration.

Using immunohistochemical techniques and mAb MT2, we describe here a novel extracellular matrix (ECM) molecule that is developmentally regulated during limb regeneration in adult newts. The MT2 antigen appears during preblastema stages, is most abundant during blastema stages, and persists, near undifferentiated cells, until digit stages. The MT2 antigen is located in an acellular layer under the wound epithelium and throughout the ECM of the undifferentiated mesenchyme as a thick, cord-like component. In unamputated limbs mAb MT2 reactivity is restricted to tendons, myotendinous junctions, periosteum and to a layer of material beneath the epidermis. In both unamputated limbs and regenerating limbs, the reactivity to mAb MT2 colocalizes closely with urodele tenascin. Immunoblot analysis of blastema extracts showed that the unreduced form of the MT2 antigen is a large, polydispersed protein of approximately the same size as tenascin. However, based upon (a) molecular weights of reduced subunits, (b) competition experiments on tissue sections, and (c) analysis of molecules immunoprecipitated by mAb MT2, we conclude that the MT2 substance is unrelated biochemically to tenascin. The results from immunoblots, enzyme digestions and DEAE-Sephacell binding studies suggest that the unreduced MT2 antigen is a large protein composed of subunits which are connected by disulfide bonds. Reduction of the MT2 antigen results in three components recognized by mAb MT2. The largest of these reduced components is a chondroitin sulfate-like glycoprotein with a molecular weight (Mr) of 310-325 x 10(3). A second component (Mr, 285-300 x 10(3)) is the core protein of the 310-325 x 10(3) glycoprotein.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of community-based, videotape, and flash card instruction of community-referenced sight words on students with mental retardation.

Community-referenced sight words and phrases were taught to adolescents with mild and moderate mental retardation using three instructional methods in two locations. Words were presented on flash cards in a school setting, on videotape recordings in a school setting, and on naturally occurring signs in the community. During each session, participants were taught one third of the words in each of these conditions and were then tested at the community sites. A constant prompt delay procedure was used to promote stimulus control to the experimenter's cue initially and then to transfer control to the textual stimuli used for training. A multiple baseline across participants design was employed. Results showed rapid acquisition of the community-referenced sight words in all three training conditions and generalization from the flash card and videotape conditions to the community sites.