Adaptive short-term plasticity in the typical reading network.

The left temporo-parietal cortex (TPC) is crucial for phonological decoding, i.e., for learning and retaining sound-letter mappings, and appears hypoactive in dyslexia. Here, we tested the causal contribution of this area for reading in typical readers with transcranial magnetic stimulation (TMS) and explored the reading network's response with fMRI. By investigating the underlying neural correlates of stimulation-induced modulations of the reading network, we can help improve targeted interventions for individuals with dyslexia. 28 typical adult readers overtly read simple and complex words and pseudowords during fMRI after effective and sham TMS over the left TPC. To explore differences in functional activation and effective connectivity within the reading network, we performed univariate and multivariate analyses, as well as dynamic causal modeling. While TMS-induced effects on reading performance and brain activation showed large individual variability, multivariate analyses revealed a shift in activation in the left inferior frontal cortex for pseudoword reading after effective TMS. Furthermore, TMS increased effective connectivity from the left ventral occipito-temporal cortex to the left TPC. In the absence of effects on reading performance, the observed changes in task-related activity and the increase in functional coupling between the two core reading nodes suggest successful short-term compensatory reorganization in the reading network following TMS-induced disruption. This study is the first to explore neurophysiological changes induced by TMS to a core reading node in typical readers while performing an overt reading task. We provide evidence for remote stimulation effects and emphasize the relevance of functional interactions in the reading network.

Online transcranial magnetic stimulation reveals differential effects of transitivity in left inferior parietal cortex but not premotor cortex during action naming.

Accumulating evidence indicates two cortical regions, the left ventral premotor cortex (PMv) and left intraparietal sulcus (IPS), are involved in spoken verb production. Some evidence also indicates these regions may be differentially engaged by transitive (i.e., object-oriented) versus intransitive actions. We explored the role of these regions during action picture naming in two experiments, each employing high frequency (10 Hz) online repetitive Transcranial Magnetic Stimulation (rTMS) in 20 participants. In Experiment 1, participants named intransitive action pictures (e.g., LAUGH) accompanied by active and sham rTMS to the left PMv, left IPS, and right superior parietal lobule (SPL; control site). Application of rTMS to PMv resulted in slower naming latencies compared to sham and control site stimulation, whereas stimulation of the IPS did not result in any significant effects. Experiment 2 employed active and sham rTMS identical to Experiment 1 with transitive action pictures (e.g., PUSH). Stimulation of both regions induced changes in naming latencies compared to sham and control site stimulation, with rTMS applied to PMv slowing responses and IPS stimulation facilitating them. Surprisingly, stimulation of the right SPL control site also slowed naming compared to sham across both Experiments. Overall, these findings indicate different roles for PMv and IPS during action picture naming. Specifically, the divergent effects of PMv and IPS stimulation in the transitive action naming task indicate different processes likely operate in the two regions during verb production. Involvement of the right SPL across both transitive and intransitive action naming might reflect visuospatial or general attention mechanisms rather than language processes per se.

Spatial orientation and postural control in patients with Parkinson's disease.

Postural instability is one of the most disabling and risky symptoms of advanced Parkinson's disease (PD). The purpose of this study was to investigate whether and how this is mediated by a centrally impaired spatial orientation. Therefore, we performed a spatial orientation study in 21 PD patients (mean age 68years, SD 8.5 years, 9 women) in a medically on condition and 21 healthy controls (mean age 68.9years, SD 5.5years, 14 women). We compared their spatial responses to the horizontal axis (Sakashita's visual target cancellation task), the vertical axis (bucket-test), the sagittal axis (tilt table test) and postural stability using the Fullerton Advanced Balance Scale (FAB). We found larger deviations on the vertical axis in PD patients, although the direct comparisons of performance in PD patients and healthy controls did not reveal significant differences. While the total scores of the FAB Scale were significantly worse in PD (25.9 points, SD 7.2 points) compared to controls (35.1 points, SD 2.3 points, p<0.01), the results from the spatialorientation task did not correlate with the FAB Scale. In summary, our results argue against a relation between perceptional deficits of spatial information and postural control in PD. These results are in favor of a deficit in higher order integration of spatial stimuli in PD that might influence balance control.

Involuntary attentional capture by speech and non-speech deviations: a combined behavioral-event-related potential study.

This study applied an auditory distraction paradigm to investigate involuntary attention effects of unexpected deviations in speech and non-speech sounds on behavior (increase in response time and error rate) and event-related brain potentials (ΔN1/MMN and P3a). Our aim was to systematically compare identical speech sounds with physical vs. linguistic deviations and identical deviations (pitch) with speech vs. non-speech sounds in the same set of healthy volunteers. Sine tones and bi-syllabic pseudo-words were presented in a 2-alternative forced-choice paradigm with occasional phoneme deviants in pseudo-words, pitch deviants in pseudo-words, or pitch deviants in tones. Deviance-related ERP components were elicited in all conditions. Deviance-related negativities (ΔN1/MMN) differed in scalp distribution between phoneme and pitch deviants within phonemes, indicating that auditory deviance-detection partly operates in a deviance-specific manner. P3a as an indicator of attentional orienting was similar in all conditions, and was accompanied by behavioral indicators of distraction. Yet smaller behavioral effects and prolonged relative MMN-P3a latency were observed for pitch deviants within phonemes relative to the other two conditions. This suggests that the similarity and separability of task-relevant and task-irrelevant information is essential for the extent of attentional capture and distraction.

Full-timing: a housing alternative for older people.

Full-timing, living year-round in a recreational vehicle, is discussed as a viable housing alternative for older people. Data were obtained from surveys distributed to 100 members of a nationally-based camping organization. Fifty-five percent of the respondents had lived in their motorhomes, fifth-wheels, or travel trailers for at least two years. Most had sold their conventional homes, planning to full-time indefinitely. Low-cost and adventurous, full-timing is discussed as a lifestyle especially suited for older people in the context of today's mobile society.

Older widows and the transference of home.

A relocation pattern, as indicated by a sample of older widows as they relocated from homes previously shared with their husbands to a metropolitan Phoenix life care facility, is presented. The suggested pattern is illuminated with quotes at each identified stage, revealing the individuals' inner feelings and motivations at those times. Characterized by relatively high income and educational levels, personal independence and prior careers, the sample is more representative of future women than those of their own age cohort. It is felt that these attributes were conducive to their apparently successful relocation.

Sex differences in institutional relocation patterns of older patients.

This article discusses sex differences in the relocation patterns of thirty-seven alert, institutionalized patients who were personally interviewed over a ten month period prior to and following a forced relocation. Trends indicate that while males scored slightly higher levels of mental alertness, females appeared to be better suited to life in the institution. The appropriateness of institutional life for males and for individuals retired from active, demanding professions is indicated as an area for future study. Application of these and similar findings in counseling situations is also an area of concern.