Cognitive Effort and Aphasia

Some researchers have suggested that impairments of individuals with aphasia on cognitive-linguistic tasks reflect an impaired ability to match effort with task demands (e.g. Murray et al., 1997, Clark & Robin, 1991). However, a direct physiological measure of effort IWA invest during such tasks is lacking. Heart rate variability is a well-studied measure of the stress response and is an indicator of the effort allocated to cognitively demanding tasks (Hansen et al., 2003). This research will utilize HRV to understand the relationship among perceptions of task difficulty, behavioral performance, and effort allocated to a verbal working memory task

Robotic milking technologies and renegotiating situated ethical relationships on UK dairy farms

Robotic or automatic milking systems (AMS) are novel technologies that take over the labor of dairy farming and reduce the need for human-animal interactions. Because robotic milking involves the replacement of 'conventional' twice-a-day milking managed by people with a system that supposedly allows cows the freedom to be milked automatically whenever they choose, some claim robotic milking has health and welfare benefits for cows, increases productivity, and has lifestyle advantages for dairy farmers. This paper examines how established ethical relations on dairy farms are unsettled by the intervention of a radically different technology such as AMS. The renegotiation of ethical relationships is thus an important dimension of how the actors involved are re-assembled around a new technology. The paper draws on in-depth research on UK dairy farms comparing those using conventional milking technologies with those using AMS. We explore the situated ethical relations that are negotiated in practice, focusing on the contingent and complex nature of human-animal-technology interactions. We show that ethical relations are situated and emergent, and that as the identities, roles, and subjectivities of humans and animals are unsettled through the intervention of a new technology, the ethical relations also shift. © 2013 Springer Science+Business Media Dordrecht

Application of Wireless Contralateral Routing of Signal Technology in Unilateral Cochlear Implant Users with Bilateral Profound Hearing Loss

Abstract Purpose: The aim of the study was to determine if contralateral routing of signal (CROS) technology results in improved hearing outcomes in unilateral cochlear implant (CI) patients and provides similar gains in speech perception in noise to traditional monaural listeners (MLs). Research Design: The study is a prospective, within-subject repeated-measures experiment. Study Sample: Adult, English-speaking patients with bilateral severe–profound sensorineural hearing loss using an Advanced Bionics CI (n = 12) in one ear were enrolled for the study. Intervention: Hearing performance in the monaural listening condition (CI only) was compared with the CROS-aided (unilateral CI + CROS) condition. Participants were tested for speech-in-noise performance using the Bamford-Kowal-Bench Speech-in-Noise™ test materials in the speech front/noise front (0 degrees/0 degrees azimuth), speech front/noise back (0 degrees/180 degrees azimuth), speech deaf ear/noise monaural ear (90 degrees/270 degrees azimuth), and speech monaural ear/noise deaf ear (90 degrees/270 degrees azimuth) configurations. Localization error was assessed using three custom stimuli consisting of 1/3 octave narrowband noises centered at 500 and 4000 Hz and a broadband speech stimulus. Localization stimuli were presented at random in the front hemifield by 19 speakers spatially separated by 10 degrees. Outcomes were compared with a previously described group of traditional MLs in the CROS-aided condition (normal hearing ear + CROS). Data Collection and Analysis: All participants were tested acutely with no adaptation to the CROS device. Statistical analyses were performed using Wilcoxon signed rank tests for nonparametric data and paired sample. Statistical significance was set to p < 0.00625 after Bonferroni adjustment for eight tests. Results: Significant benefit was observed from unaided to the CI + CROS–aided condition for listening in noise across most listening conditions with the greatest benefit observed in the speech deaf ear/noise monaural ear (90 degrees/270 degrees azimuth) condition ( p < 0.0005). When compared with traditional MLs, no significant difference in decibel gain from the unaided to CROS-aided conditions was observed between participant groups. There was no improvement in localization ability in the CROS-aided condition for either participant group and no significant difference in performance between traditional MLs and unilateral CI listeners. Conclusions: These findings support that unilateral CI users are capable of achieving similar gains in speech perception to that of traditional MLs with wireless CROS. These results indicate that the use of wireless CROS stimulation in unilateral CI recipients provides increased benefit and an additional rehabilitative option for this population when bilateral implantation is not possible. The results suggest that noninvasive CROS solutions can successfully rehabilitate certain monaural listening deficits, provide improved hearing outcomes, and expand the reach of treatment in this population

Hearing preservation surgery: Psychophysical estimates of cochlear damage in recipients of a short electrode array

In the newest implementation of cochlear implant surgery, electrode arrays of 10 or 20 mm are inserted into the cochlea with the aim of preserving hearing in the region apical to the tip of the electrode array. In the current study two measures were used to assess hearing preservation: changes in audiometric threshold and changes in psychophysical estimates of nonlinear cochlear processing. Nonlinear cochlear processing was evaluated at signal frequencies of 250 and 500 Hz using Schroeder phase maskers with various indices of masker phase curvature. A total of 15 normal-hearing listeners and 13 cochlear implant patients (7 with a 10 mm insertion and 6 with a 20 mm insertion) were tested. Following surgery the mean low-frequency threshold elevation was 12.7 dB (125–750 Hz). Nine patients had postimplant thresholds within 5–10 dB of preimplant thresholds. Only one patient, however, demonstrated a completely normal nonlinear cochlear function following surgery—although most retained some degree of residual nonlinear processing. This result indicates (i) that Schroeder phase masking functions are a more sensitive index of surgical trauma than audiometric threshold and (ii) that preservation of a normal cochlear function in the apex of the cochlea is relatively uncommon but possible