A signal processing component to Broca's aphasia functor deficits.

We conducted a modified replication of K. M. Heilman and R. J. Scholes [Cortex 12, 258-265, 1976] test of functor comprehension in aphasia, controlling the acoustic dimensions of the key function words: 9 Broca patients heard 4 sentence pairs differing only in the post-verb placement of the. They made forced choices between 4 line drawings: one which depicted the correct action, one which depicted the action of the other member in the pair, and two which contained depictions of different figures and actions altogether. Each of the 8 sentences was played in 2 conditions: one with NORMAL intonation, and another with an acoustically more SALIENT post-verbal the. Both of Heilman and Scholes' principal results were successfully replicated, and a SALIENT effect was also discovered, supporting a signal processing component to the Broca syndrome functor deficit.

Affective responses to commercial and experimental auditory alarm signals for anaesthesia delivery and physiological monitoring equipment.

The affective response of subjects to the sounds of commercial and experimental auditory alarm signals was tested using a standard experimental protocol for measuring mood states and changes. Both types of signal evoked affective response. The commercial signals, however, evoked more response than the experimental signals, and that response was more negative in affect. A subset of the experimental signals, distinguished by specific acoustic characteristics, evoked particularly low levels of affect. The implications of low-affect alarms for the operating room are discussed.

Audible alarm signals for anaesthesia monitoring equipment.

To address the problem of auditory alarms on anaesthesia monitoring and delivery devices whose signal is masked by the noises of other operating room equipment, a set of signals having the characteristics of spectral richness, frequency modulation, and temporal patterning were electronically generated, and were tested for detectability against operating room equipment noises in a laboratory setting. A set of signals was identified which can, under these circumstances, be detected with at least 93% accuracy at -24 dB signal-to-noise ratio.