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The theory that various features of autism spectrum disorders (ASD) can be explained by differences in the learning (or "predictive coding") process is growing in popularity. However, extant studies have focused on the domain of sensory perception, i.e., learning what to expect in the visual or auditory domains. It is thus unclear whether such models are restricted to the perceptual domain, or whether they are outlining differences in domain- general learning processes. Consequently, how such theories can explain the social and motor features of ASD is currently unclear. The first part of the current thesis asks whether autistic adults exhibit differences, compared to non-autistic adults, with respect to social learning and motor learning. The second part of this thesis focuses in detail on one of these learning types - social learning. Here I investigate the neurochemical mechanisms that underpin social learning and ask whether they are dissociable from the neurochemical mechanisms that underpin learning from one's own individual experience (individual learning). In integrating these results with the wider literature, I reflect upon the broader question of whether there are common domain-general learning mechanisms, or domain (e.g., social, motor, individual) specific learning "modules". Together the studies presented in this thesis implicate the dopaminergic neurotransmitter system in both social and individual learning. Results support the view that there are domain-general neurochemical mechanisms that support various types of learning. These results do not, however, support the view that autistic adults exhibit differences in these domain-general learning processes. That is, our empirical work showed no differences in either social or motor learning when comparing autistic and non-autistic adults. These results do not add support for impaired predictive coding as a core deficit that can explain social and motor atypicalities in autism, but rather force us to think more critically about what overarching conclusions can be drawn from studies of predictive coding in autism within the perception domain.

This research describes strategies used to improve student achievement in a foreign language class through the use of effective study skills. The targeted population included high school students in a first year foreign language class. Evidence for the problem of low achievement came from teacher observations, student surveys, and low assessment scores. Analysis of probable cause data revealed that students were not successful in their classes due in large part to their lack of effective study skills. Students also did not know what learning strategies to use for specific tasks and chose ineffective learning strategies to help them learn the language. A review of solution strategies confirmed that students needed to receive instruction on effective language learning strategies during regular class instruction, with the teacher best suited to providing this instruction. Strategies included ones that addressed all areas of language learning (vocabulary, reading, writing, listening, and speaking). Over several months, students received instruction in the strategies, wrote in their journals, and completed surveys. Results showed that students were able to use the language learning strategies to achieve higher success. Students reported feeling more comfortable with the various aspects of language learning when using these language learning strategies. Language learning strategies questionnaire is appended. (Contains 17 references.) (SM)

In an attempt to better understand the superior radiation resistance of InP solar cells, 2 MeV proton irradiation damage was studied in Zn and Cd doped InP Schottky diodes. The damage was analyzed using the capacitance/voltage technique to study carrier loss, and using DLTS to study the irradiation induced deep levels. The carrier removal rate was found to be identical in both Zn and Cd doped InP. The DLTS spectrum of Cd doped InP was studied in detail for the first time: it was identical to the spectrum of comparably Zn doped InP. Two irradiation induced deep levels dominated the DLTS spectra in Cd and Zn doped InP, H3 at E v + 0.28 eV and H5 at E v + 0.57 eV. The defect H4 at E v + 0.37 eV was not observed in the heavily Zn or Cd doped samples, but was observed in lightly Zn doped samples. This effect is related to the dependence of the annealing rate of H4 on dopant concentration and type. The introduction rate of H3 was identical in both materials, but the introduction rate of H5 was lower in Cd doped InP. This effect is attributed to the slower diffusion rate of Cd and its effect on the formation of H5, a defect-dopant complex. The annealing rates of the defects were higher in Cd doped InP than in Zn do ped InP. A model is suggested in which the defects H3 and H4 are eliminated at a dopant interstitial created during irradiation. The slower diffusion of Cd leads to slower elimination of the interstitial at sinks. The higher interstitial concentration results in an increased defect annealing rate. The slower diffusion rate of Cd inhibits the formation of H5, but its concentration grows rapidly on annealing. After annealing the concentration of H5 was nearly the same in comparably Zn and Cd doped InP. The enhanced annealing rates of H3 and H4, and the reduced formation rate of H5 make Cd doped InP more radiation resistant than Zn doped InP.

Sarcoidosis is a multisystem, granulomatous disorder of unknown etiology, most often presenting between the ages of 20 and 40 and in African Americans. The objective of this work was to examine racial differences in sarcoidosis risk and heterogeneity in risk among families, and to test for evidence of genetic inheritance in selected sarcoidosis families. First, all newly diagnosed cases occurring between 1990 and 1994 among members of the Health Alliance Plan health maintenance organization in Detroit, Michigan were identified. Annual incidence, in number of new cases per 100,000, was highest in 30-39 year old African American females (107). Overall, African Americans had about a threefold higher age adjusted annual incidence (36.5) compared with Caucasians (11.3). Next, heterogeneity in familial risk of sarcoidosis was examined in 3,395 siblings and parents of 558 index cases (361 African American, 197 Caucasian) diagnosed at Henry Ford Hospital between 1965 and 1994. Using the age-, race- and sex-specific cumulative incidence of sarcoidosis in the sample, a statistically significant heterogeneity of familial risk (p $

I research my life and my professional practice, which extends over three decades, as an elementary classroom teacher. My autobiographical inquiry focuses on three epiphanies, or pivotal points in my life: my relationship with the African American community, leaving a Religious Community and entering marriage, and the return to graduate study. The history and development of myself as a writer is interwoven with those critical moments where my personal life and my teaching practice are interrelated. I have experimented with a narrative style, paralleling the experiences of my students with my own experiences as a growing and changing human being. Integral to my teaching story is my engagement in writing through active participation in my third and fourth grade classroom community writers' process. I argue that consistent autobiographical writing through multi-purpose journals, letter writing as by electronic mail, and life stories serves a transformative function. The autobiographical text of my life explores a way of knowing which is shaped by the reflexive practice of my narrative of experience. These reflexive narratives of experience are also practiced by the students in my writing/reading classroom, as well as by other persons who interact in our classroom learning. I view the relationships of those in my classroom as educational and present a narrative that invites the reader into my life and classroom through the eyes of a preservice teacher. The educational significance of my study lies in the ways in which I have been influenced to change my practice through writing the autobiography of my life, a method critical to the reshaping of my pedagogical perspectives. I view engagement in writing as a community-based experience, critical to self-development and valuing the teacher as learner. Our classroom writers' community provides a forum for young writers to engage in life study, to interact in their own learning process, and to assume responsibility for self and others.