<p> This dissertation focused on how the affiliation and engagement practices that contribute to social cohesiveness result in changes to conversation for three individuals with aphasia that were part of group therapy that targeted improved communication through conversation. It revealed how those changes were made manifest by employing a qualitative research design which allowed the researcher to discover how social cohesiveness is demonstrated in conversation. This design included the administration of aphasia batteries that are widely used in the area of aphasiology and were administered prior to and subsequent to the period of conversation treatment. The design further included medical and clinic records that informed the researcher of the participant's physical and communicative abilities. The primary research tool was Conversation Analysis which by virtue of its dual characteristics of being context-sensitive yet context-free allowed the researcher to examine behaviors in an authentic context and observe patterns within and across participants. Additionally, post-semester interviews served as a lamination tool that, along with the primary and other secondary data sources, would verify or refute the patterns of conversation changes. </p><p> The resulting data were then analyzed for patterns of conversation change and formed three areas of interest; patterns of conversation changes that revealed the member's growing orientation toward group cohesiveness, patterns of changing compensatory strategy use, and changing patterns of turn-taking. The results of this study demonstrate the importance of social cohesiveness as an integral part of group conversation treatment and its effect, as a catalyst, upon improving conversation ability. Additionally, it illustrates group cohesiveness as a multi-dimensional construct that involves an orientation to task and interpersonal cohesiveness. Further, it explicates the relationship between an individual's functioning, personal factors, and context as influencers of the aphasic's demonstration of social cohesiveness. This study proffers important implications concerning the value of a qualitative research design for studying communication changes in aphasia and the essential employment of constructivist approaches to communication therapy for individuals with aphasia. These clinical implications shape the assessment and intervention practices of clinicians who recognize the transformative power of a constructivist approach that requires the situation of treatment in an authentic context. </p>

<p> Lowered motivation can influence the involvement of adults with brain injury in the rehabilitation process, ultimately affecting the extent of their progress. This within-subject, pretest/posttest design examined the effects of an education program focusing on concepts of neuroplasticity on 34 adults with brain injury. Quantitative data was taken from pre-presentation and post-presentation surveys and was analyzed for significant change. Results indicated that the presentation was successful in increasing (a) the knowledge of neuroplasticity as evidenced by significant change in two out of three items, and (b) level of motivation as evidenced by significant change in six out of nine items. Effects of age, education level, and time post-injury were discussed. Study conclusions validate the use of education to increase motivation in people with brain injury, and provides new information about the use of neuroplasticity in education.</p>

<p> The field of motor speech disorders in Greek is substantially underresearched. Additionally, acoustic studies on lexical stress in dysarthria are generally very rare (Kim et al. 2010). This dissertation examined the acoustic and perceptual effects of Greek dysarthria focusing on lexical stress. Additional possibly deviant speech characteristics were acoustically analyzed. Data from three dysarthric participants and matched controls was analyzed using a case study design. The analysis of lexical stress was based on data drawn from a single word repetition task that included pairs of disyllabic words differentiated by stress location. This data was acoustically analyzed in terms of the use of the acoustic cues for Greek stress. The ability of the dysarthric participants to signal stress in single words was further assessed in a stress identification task carried out by 14 na&iuml;ve Greek listeners. Overall, the acoustic and perceptual data indicated that, although all three dysarthric speakers presented with some difficulty in the patterning of stressed and unstressed syllables, each had different underlying problems that gave rise to quite distinct patterns of deviant speech characteristics. The atypical use of lexical stress cues in Anna's data obscured the prominence relations of stressed and unstressed syllables to the extent that the position of lexical stress was usually not perceptually transparent. Chris and Maria on the other hand, did not have marked difficulties signaling lexical stress location, although listeners were not 100% successful in the stress identification task. For the most part, Chris' atypical phonation patterns and Maria's very slow rate of speech did not interfere with lexical stress signaling. The acoustic analysis of the lexical stress cues was generally in agreement with the participants' performance in the stress identification task. Interestingly, in all three dysarthric participants, but more so in Anna, targets stressed on the 1^st syllable were more impervious to error judgments of lexical stress location than targets stressed on the 2^nd syllable, although the acoustic metrics did not always suggest a more appropriate use of lexical stress cues in 1^st syllable position. The findings contribute to our limited knowledge of the speech characteristics of dysarthria across different languages.</p>

<p> This study investigated two classifications of semantic features, feature importance and feature relevance, to verify if they differentially influence lexical semantic knowledge in individuals with aphasia. Feature <i>importance </i> is defined as "how important a feature is in defining a concept" (Hampton,1979), while feature relevance represents the "core meaning of a concept" (Sartori, Lombardi &amp; Mattiuzi, 2005). </p><p> A sorting task was used with 20 volunteer participants with aphasia to investigate the semantic processing involved in the association of semantic features with nouns. A corpus of 18 nouns was displayed in front of each participant in groups of three along with a card containing the word "UNRELATED." The participants were given a deck of 18 cards containing features corresponding to the nouns and to the unrelated category, and were verbally instructed to sort the deck of cards into each of the four designated piles. The semantic features on the cards were rated as high, mid and low importance (HI, MI, LI) and <i>high, mid</i> and <i>low</i> relevance (HR, MR, LR). </p><p> Analysis was completed using a two-way between-subjects ANOVA to determine was whether the mean scores at the three different levels (e.g., low, mid and high) of importance and relevance differed, and to analyze if there was an interaction between the two classifications. The participants were able to assign <i>high importance</i> features with nouns more accurately than they did <i>mid</i> and <i>low importance</i> features. Feature <i>relevance</i> did not differentially influence noun-feature association. These results indicated that the ability of individuals with aphasia to accurately associate features with nouns is influenced by levels of feature importance. </p><p> In conclusion, this study found that individuals with aphasia are more cognitively sensitive to <i>high</i> level versus <i>low</i> level feature importance and the effect does not extend to a<i> mid</i> level of importance. The study also demonstrated that the levels of feature <i> relevance</i> did not differentially influence the ability of individuals with aphasia to associate semantic features with their appropriate nouns. Potential clinical implications and study limitations were discussed.</p>

<p> The acquisition of literacy skills influences both the perception and production of spoken language. The connection between spoken and written language processing develops differently in individuals with varying degrees of reading skill. Some specific phonological and orthographic factors which play a role in this developmental course include neighborhood density, orthographic transparency, and phonotactic probability. In the current study, nonword stimuli which contain manipulations of the above factors were created. Participants repeated or read aloud the nonwords. Three groups of readers participated: adults with typical reading skills, children developing reading skills typically, and adults demonstrating low levels of reading proficiency. Analyses of implicit linguistic processing, including measures of segmental accuracy, segmental variability, and articulatory stability, were conducted. Results indicated that these three groups followed a consistent pattern on all three measures, in that the typical adults demonstrated the strongest performance, the children demonstrated the weakest performance, and the adults with low levels of reading skill demonstrated intermediate performance. All three groups improved in both phonological and motor learning with practice, but only the adults with low reading skills demonstrated learning as a direct consequence of orthographic transparency. Finally, reading skill was correlated with articulatory stability in both groups of adults. These data make an important contribution to the understanding of the typology of reading disorders, as well as the influence of orthographic factors on typical language and reading development.</p>

<p> This study was a within subject, pretest posttest design intended to determine if a three session parent-training program (PTP) would be effective in facilitating morphosyntax in children with or suspected of having specific language impairment (SLI) over the course of 5 weeks. This was measured with the SPELT-P2. In addition, the researcher aimed to determine if parents learned from and were satisfied with the PTP, which was measured by a questionnaire given before and after the PTP was implemented. There were six parent-child dyads in this study. Three children participants demonstrated an increase in standard scores on the SPELT-P2 and three children participants demonstrated a decrease in standard scores. Parent participants demonstrated an overall increase in scores on knowledge, perceptions, and strategies learned during the PTP. Results and clinical implications are discussed.</p>

This thesis investigated sentence comprehension impairments in patients with dementia of the Alzheimer's-type (DAT). The first three experiments investigated the nature of the impairments using different tasks. Across tasks, patients' performance by syntactic complexity, but was poorer for sentences that had more propositions. Results are discussed in terms of a post-interpretive processing impairment in these patients. Two additional experiments investigated possible determinants of sentence comprehension impairments in DAT. One employed a dual-task paradigm to examine the effect of increasing the processing load associated with sentence comprehension. The other examined processing resource limitations in the patients tested in the first and second experiments by employing a battery of tasks designed to measure all aspects of working memory. In both experiments, evidence for processing resource limitations was seen in impaired performance on a concurrent task in dual-task conditions. Results of the fifth experiment also provided evidence that DAT patients' sentence comprehension impairments are correlated with processing resource limitations.

The present study is an investigation of on-line and off-line processing of verb tense in individuals with developmental language impairment. Three groups of subjects performed two experiments, (1) a lexical decision task (on-line) and, (2) a grammaticality judgement task (off-line). Grammaticality was controlled by the manipulation of tense for regular and irregular verbs. Participants were six members of a large British familial aggregation diagnosed with developmental language impairment, six of their unaffected relatives, and seven unaffected Canadian individuals. The results of the lexical decision task indicate that the reaction times of the affected group were slower than the Canadian control group. Unlike the control groups, the affected group was influenced by regular and irregular verb type distinctions. Reaction times across grammatical and ungrammatical conditions did not differ among the three groups. The groups differed significantly in the off-line task; accuracy of the affected subjects was poor, while the control subjects were highly accurate. The implications of these findings for linguistic theories of SLI such as the missing rules hypothesis (Gopnik, in press) are discussed.

The present experiment was conducted to explore the time-course of lexical ambiguity resolution in normal control (NC) subjects and the nature of right hemisphere-damaged (RHD) and left hemisphere-damaged (LHD) patients' impairments in this process. NC, RHD and LHD subjects performed a cross-modal lexical decision task, in which they heard sentence contexts that were biased toward the dominant or subordinate meanings of ambiguous words occurring before the end of the sentence. Written target words related to the dominant or subordinate meaning of the ambiguous words were introduced either at the onset of the ambiguous word (immediate condition), or 1000 ms later (delayed condition). Results revealed that both dominant and subordinate meanings were primed in the immediate condition, irrespective of context type or group. In the delayed condition, only the contextually-appropriate dominant meanings were primed in normal control subjects, whereas both patient groups showed significant priming only for the contextually-inappropriate dominant meanings. Findings for the NC subjects are interpreted in support of a modular model of lexical ambiguity resolution, and more specifically of an exhaustive access view. Patients' results are discussed with reference to a delayed suppression mechanism of inappropriate meanings, which is thought to be involved in these patients' language comprehension deficits.

The development of language in physically handicapped individuals using augmentative and alternative communication (AAC) systems has not been described. Therefore our understanding of the role of AAC language encoding limitations in the development of syntax is limited. This study examined adult AAC system users' knowledge of an English grammatical process which cannot be encoded in lexically based AAC systems. Because it is not possible to mark past tense with affixation in Blissymbolics, a meaning based graphic communication system, past and future tense are neutralized syntactically. The subjects, two congenitally physically handicapped adults with normal hearing, vision, and intelligence, accessed their Blissymbol displays using four-digit eyegaze number codes. The subjects were shown a novel mechanism to enable use of affixation through manipulation of the four-digit codes. Results indicate that the subjects had developed knowledge of this grammatical rule despite the encoding limitations of their AAC systems. Clinical implications are discussed.