Brief Report: Two Day-Date Processing Methods in an Autistic Savant Calendar Calculator.

Special ability in computing the day of week for given dates was observed in a 24 year-old male (FB) diagnosed with Asperger syndrome. FB performed almost flawlessly (98.2%) both with past and future dates, over a span of 40 years. Response latency was slower as temporal remoteness of future dates increased. Within the future timespan, FB's performance was consistent with the active use of calendar regularities. On the contrary, within the past timespan (for which no remoteness effect was seen), his performance was mainly linked to memory retrieval of personal events. The case presented here complements the existent literature on calendar calculators, as, for first time, two distinct day-date processing styles are described in the same individual.

Coverbal gestures in the recovery from severe fluent aphasia: a pilot study.

UNLABELLED: This post hoc study investigated coverbal gesture patterns in two persons with chronic Wernicke's aphasia. They had both received therapy focusing on multimodal communication therapy, and their pre- and post-therapy verbal and gestural skills in face-to-face conversational interaction with their speech therapist were analysed by administering a partial barrier Referential Communication Task (RCT). The RCT sessions were reviewed in order to analyse: (a) participant coverbal gesture occurrence and types when in speaker role, (b) distribution of iconic gestures in the RCT communicative moves, (c) recognisable semantic content, and (d) the ways in which gestures were combined with empty or paraphasic speech. At post-therapy assessment only one participant showed improved communication skills in spite of his persistent language deficits. The improvement corresponded to changes on all gesturing measures, suggesting thereby that his communication relied more on gestural information. No measurable changes were observed for the non-responding participant-a finding indicating that the coverbal gesture measures used in this study might account for the different outcomes. These results point to the potential role of gestures in treatment aimed at fostering recovery from severe fluent aphasia. Moreover, this pattern of improvement runs contrary to a view of gestures used as a pure substitute for lexical items, in the communication of people with severe fluent aphasia. LEARNING OUTCOMES: The readers will describe how to assess and interpret the patterns of coverbal gesturing in persons with fluent aphasia. They will also recognize the potential role of coverbal gestures in recovery from severe fluent aphasia.

Effect of a visual distractor on line bisection.

Previous studies have shown that a flanking distractor produces a spatial bias during line bisection. In the present study, we investigated whether that bias depends on perceptual or motor components. Participants were asked to bisect a horizontal line, or to reach towards a dot, with or without vision of their hand. The line and the target could be flanked by a distractor. Movement trajectories and endpoints were consistently deviated away from the location of the distractor in the bisection task, but not in the reaching task, irrespectively of whether the participants had online visual feedback from their moving hand. It is suggested that flanking distractors influence perceptual localization of the subjective mid-point during line bisection.

Discourse information content in non-aphasic adults with brain injury: a pilot study.

BACKGROUND: The functional evaluation of discourse informativeness is widely used in both clinical practice and research, and impoverished and confused discourse has been described in individuals with traumatic brain injury (TBI). These symptoms have been related to language processing deficits at the macrolinguistic level. However, the functional counterpart of these deficits, i.e. poor informativeness in standardized analysis of elicited speech samples, has been less explored. METHODS AND PROCEDURES: In this pilot study, samples of narrative discourse from 10 non-aphasic TBI adults and 28 healthy adults were examined to study the relationship between standardized measures of informativeness (i.e. Correct Information Unit analysis) and language processing errors at the macrolinguistic level and to compare performance of the two groups. MAIN OUTCOMES AND RESULTS: The participants with TBI did not produce relevant within-sentence errors and information content of their narratives was not different from that of the healthy participants. However, their production of errors of cohesion, local coherence and global coherence was significantly greater. These macrolinguistic errors corresponded to reduced levels of information efficiency (% CIUs score). CONCLUSIONS: Functional measures of speech informativeness such as the CIU scores may be useful for the clinical assessment of discourse processing deficits in TBI individuals without aphasic symptoms.

Narrative language in traumatic brain injury.

Persons with traumatic brain injury (TBI) often show impaired linguistic and/or narrative abilities. The present study aimed to document the features of narrative discourse impairment in a group of adults with TBI. 14 severe TBI non-aphasic speakers (GCS<8) in the phase of neurological stability and 14 neurologically intact participants were recruited for the experiment. Their cognitive, linguistic and narrative skills were thoroughly assessed. The group of non-aphasic individuals with TBI had normal lexical and grammatical skills. However, they produced narratives with increased errors of cohesion and coherence due to the frequent interruption of ongoing utterances, derailments and extraneous utterances that made their discourse vague and ambiguous. They produced a normal amount of thematic units (i.e. concepts) in their narratives. However, this information was not correctly organized at micro- and macrolinguistic levels of processing. A Principal Component Analysis showed that a single factor accounted for the production of global coherence errors, and the reduction of both propositional density at the utterance level and proportion of words that conveyed information. It is hypothesized that the linguistic deficits observed in the participants with TBI may reflect a deficit at the interface between cognitive and linguistic processing rather than a specific linguistic disturbance.

Anosognosia for memory deficit in amnestic mild cognitive impairment and Alzheimer's disease.

OBJECTIVE: to investigate patterns of anosognosia for memory deficit in subjects with amnestic mild cognitive impairment (MCI) and Alzheimer's disease (AD). METHODS: the study involved twenty-five subjects with MCI, 15 with mild AD and 21 normal controls (NC). Subjective rating of memory functioning was assessed with a six-items questionnaire that was administered before and after memory testing; an informant version from caregivers gave a discrepancy score (SRD). In the Objective Judgement (OJ) task, aiming to evaluate memory-monitoring abilities, subjects were requested three times to predict their memory performance in recalling words from a list of ten. Then they had to recall the words. Prediction accuracy was computed by subtracting the predicted performance from the actual performance. RESULTS: MCI and AD showed reduced awareness of memory difficulties at the SRD and did not change their rating of these difficulties after memory testing. At the OJ task, MCI and AD consistently overestimated their memory performances as compared with NC. The SRD and OJ measures were not correlated with some patients being impaired on only one measure. Only the OJ measure was significantly related to executive functioning. CONCLUSIONS: AD and MCI subjects show unawareness for memory deficit and significant memory-monitoring disorder. This confirms that anosognosia is an important symptom of MCI. Similarities of patterns of impaired awareness between AD and MCI supports the view of a continuum of the anosognosia phenomenon in MCI and AD.

Effects of spatiotopic factors on bisection of radial lines.

Under visual guidance normal subjects usually misbisect radial lines farther than the true midpoint (distal bias). We investigated whether this distal bias is constant across the peripersonal space or it varies by varying the distance of the stimulus from the subject. Subjects were asked to bisect radial lines presented below eye level either in the near or far peripersonal space. The results showed an increase of distal bias in the far-space. This finding suggests that the influence of spatial factors on bisection of radial lines is not constant across the peripersonal space. Distal bias increases as a function of the distance of the stimulus from the subject, according to a spatiotopic processing scheme.

Brief report: error pattern in an autistic savant calendar calculator.

Special ability in computing the day of the week from given dates was observed in a 18 years old male, L.E., suffering from autism. Neuropsychological testing revealed severe deficits in all cognitive domains and poor explicit knowledge of calendar structure. The subject scored well above the chance level on dates of the past and future decades. Error rate and response latency increased with temporal remoteness of dates. Most of errors were in indicating the weekday before or after that of date stimulus. The performance and error pattern suggest that L.E. used "encapsulated" computation algorithm(s) for the day of week task.

Age-related differences in the production of textual descriptions.

Narratives produced by 69 healthy Italian adults were analyzed for age-related changes of microlinguistic, macrolinguistic and informative aspects. The participants were divided into five age groups (20-24, 25-39, 40-59, 60-74, 75-84). One single-picture stimulus and two cartoon sequences were used to elicit three stories per subject. Age-related differences were found with respect to semantic paraphasias, paragrammatisms, syntactic complexity, degree of both local and global coherence, local coherence errors (like ambiguous referencing), and in the level of informativeness conveyed by the stories. The results showed some null effects of age, some effects with a sharp drop in performance in the oldest group, and several effects suggesting a gradual decrease in performance across age groups. No age differences were found with respect to phonological selection and noun-verb ratio. In the proportion of details vs. main themes, the results indicated a possibly better story construction ability in the middle aged (40-59) and young elderly (60-74) groups compared to the younger or the oldest group. Story-type (single picture vs. picture sequence) had a significant influence on some macrolinguistic and informativeness measures.

Referential communication in Alzheimer's type dementia.

This paper investigates factors that underlie reduced informative content and lack of reference in the discourse of patients with Alzheimer's Type Dementia (DAT). Patients with DAT, fluent aphasics and normal controls were given a referential communication task structured to assess lexical encoding of information, pragmatic/conceptual elaboration of information and effectiveness in establishing reference. The subjects also received standardised aphasia tests (CADL, Holland, 1980; and Cookie Theft Picture Description, Nicholas and Brookshire, 1993). Comparable reduction of lexical encoding of information was found in the discourse of aphasic and DAT participants both on the referential communication task measures and on the standardised evaluation with the Cookie Theft Picture Description test. However, the DAT subjects' discourse on the referential communication task was less efficient in establishing reference than that of the aphasics since the former presented more misunderstandings and required more explicit prompts from the listener. Furthermore, the DAT language on the referential communication task contained confounding and irrelevant information; also, the number of these errors correlated negatively with their referring abilities. Results of the CADL test confirmed that the DAT participants had less communicative effectiveness than their lexical deficit alone predicted. Finally, examination of the performance of individual DAT subjects showed that lexical encoding of information could dissociate from effectiveness in making reference. These findings support the view that difficulty in pragmatic/conceptual elaboration of discourse information content plays a substantial role in the development of reduced information content and lack of reference of DAT "empty speech". These results are discussed in the framework of the hypothesis of early attentional/executive impairment in DAT (Perry and Hodges, 1999).

Coverbal gestures in Alzheimer's type dementia.

Patterns of conversational gestures were analysed in subjects with Alzheimer's type dementia (DAT), fluent aphasics with a primarily lexical-semantic deficit (FA) and normal subjects. The FA subjects produced twice as many gestures as the normal participants with a normal percentage of gestures that showed semantic features of the lexical items in concurrent speech (iconic). A comparable lexical-semantic deficit together with a deficit in conceptual organisation of information corresponded to a normal gesturing rate in the DAT subjects; however, the percentage of iconic gestures was reduced. Gestures were also analysed in four DAT patients whose communicative performance indicated primarily lexical-semantic (2 patients) or conceptual deficit (2 patients). In the two DAT patients with lexical-semantic deficit, the gesture pattern was like that of the FA patients; in the other two, the pattern of the DAT group was observed. These results agree with previous findings that DAT "empty" speech corresponds to reduced production of gestures showing semantic features (Glosser et al., 1998). However, the comparison between DAT with primarily lexical-semantic or conceptual deficits indicates that the nature of the cognitive impairment underlying poor information content and lack of reference in DAT discourse constrains the production of conversational gestures by patients with this disease. These findings are at variance with the hypothesis of parallel dissolution of speech and gestures in language disorders after brain damage (Cicone et al., 1979; McNeill, 1992; Glosser et al., 1998).

The role played by the right hemisphere in the organization of complex textual structures.

Eleven patients with right hemisphere damage (RHD), 11 left hemisphere damaged (LHD) nonaphasic subjects, and 11 neurologically intact controls were given three story description tasks. The two brain-damaged groups had no language, visuospatial, memory, or conceptual deficits on standardized neuropsychological testing. In the first experiment, the subjects were asked to retell previously read stories. In the second they had to tell stories which were depicted in cartoon-like fashion. In the third experiment, the story content was also depicted but pictures were given unordered so that the participants had first to arrange them in a plausible sequence. The elicited narratives were analyzed with a method which allowed examining within-sentence (lexical selection and syntactic complexity) and between-sentence (cohesion and coherence) processing abilities of the three groups. In the first experiment all groups performed quite well on both within- and between-sentence measures. In the two picture description tasks, however, the performances of the right hemisphere damaged subjects were poorer than those of normal controls when examined in terms of information content or coherent and cohesive aspects of narrative production. These findings agree with the hypothesis that RHD subjects are impaired in deriving from visual information the mental model of a story. They also indicate that clinical methods for analyzing structural aspects of discourse are suitable to identify these symptoms.

Increased cerebrospinal fluid levels of 3,3',5'-triiodothyronine in patients with Alzheimer's disease.

Cerebrospinal fluid (CSF) levels of rT(3) were evaluated in 21 euthyroid patients with overt Alzheimer's disease (AD) and 18 matched healthy controls. The assessment also included transthyretin and total T(3) and T(4) CSF concentrations. Despite normal circulating thyroid hormone levels, AD subjects showed significantly increased rT(3) levels and an increased rT(3) to T(4) ratio in the face of unchanged CSF total T(4) and transthyretin levels. These results suggest an abnormal intracerebral thyroid hormone metabolism and possibly the occurrence of brain hypothyroidism, either as a secondary consequence of the ongoing process or as a cofactor in the progression of the disease.

The Frontal Assessment Battery (FAB): normative data from an Italian sample and performances of patients with Alzheimer's disease and frontotemporal dementia.

The Frontal Assessment Battery (FAB) is a short neuropsychological tool aiming to assess executive functions at the bedside. Two-hundred and thirty-six normal controls were administered the FAB and three other tasks assessing attentional and executive functions. The FAB was also administered to 28 patients suffering from mild Alzheimer's disease (AD, n. 15 subjects) or frontotemporal dementia (FTD, n. 13 subjects). The FAB showed good concurrent and discriminant validity and high internal consistency. Test-retest and inter-rater reliability were fairly good. A multiple regression analysis showed a significant positive effect of education and a negative effect of age. Cut-off values of non-parametric distribution were computed. A difference on FAB scores within dementia patients was observed, with subjects with FTD performing worse than patients suffering from AD.