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These results support the hypothesis that intelligibility scores are poor predictors of listeners' comprehension in real communication situations. Intelligibility and comprehension scores appear to provide different insights, the first measure being centered on speech signal transfer and the second on communicative performance. Both theoretical and practical implications for the use of speech intelligibility tests as indicators of speakers' performances are discussed.

In a running memory span task, the participants are presented with a list of items (e.g. numbers or words) of an unknown length, because this length varies from trial to trial. In one variation of the procedure the participants must report a certain fixed number of items (e.g. four) from the end of the list. According to Morris and Jones (British Journal of Psychology, 81, 111-121, 1990), the recalled items must be updated in memory as the presentation of the list progresses. Ruiz, Elosúa and Lechuga (The Quarterly Journal of Experimental Psychology, 5, 887-905, 2005) noted that an active strategy implies an inhibition in memory of the final discarded items, and did not find results which supported this hypothesis. The aim of this study is to check whether or not participants adopt an active processing strategy in extreme conditions. Experiment 1 uses catch trials, which induce the participants not to discard the first items of the lists, and also short lists (of 4, 7, 8, 9 and 10 items); these could be considered optimal conditions for updating. However, it should also be pointed out that with an upper limit of 10 items per list, participants could try to memorise the whole list in most of the trials. One way to discourage this strategy is including lists well over span (e.g. 14-26 items). The purpose of Experiment 2 was to analyse the 10-item lists in two conditions: within a context of much longer lists (well over span) in most of the trials and within a context of shorter lists (data of Experiment 1). Results in both experiments, from the analysis of location errors, indicate that even in these conditions the participants do not seem to carry out the supposed active updating of the memory set.

A positive recency effect in a running-span recognition procedure was obtained in Experiment 1 for hits and for intratrial false alarms. In running recall procedures, recency does not fit well with an active updating hypothesis. In Experiment 2, in which the beginning of the target set was marked with a cue upon presentation, the recency effects disappeared. In Experiments 3 and 4 participants were forced to maintain 2 items in memory until the last one was presented for recognition. These three items were the target set. When the last item presentation was uncertain-because of the variable length list-an unexpected negative recency effect appeared. An explanation for this change from positive to negative recency is offered based on the sharing of attentional resources put forward by others for similar procedures.

Loudspeaker directivity and frequency response are of great importance for speech intelligibility estimation. In this work their respective influence is introduced in a new predictor. Properties of the model are in good agreement with expected variations of scores when radiation and frequency response are modified. An experiment shows the accuracy of the predicted scores. Limitations of the model are discussed and future research perspectives are presented.

During long flights, pilots can nap in the cockpit. On daily short-haul rotations, pilots may be tired. Their speech wasanalyzed in twoexperiments corresponding to these flight situations: firstly after being wokenupinalaboratory sleep inertia experiment, secondly at different airplane stopovers. Measurements of vowel acoustic parameters covered the time and spectral domains as well as the phase space. In addition to classical features and to the maximal Lyapunove xponent drawn from the chaos theory,anadditional parameter wasintroduced: the Digital Amplitude Length (DAL ). The results showt hat al arge number of acoustic characteristics are modified in the sleep inertia experiment. Only afew of them are modified in the case of fatigue and drowsiness induced in the consecutive daily short flights. The airplane'sCockpit Vo ice Recorder (CVR)was used for the second experiment and acomparative vowel analysis wasperformed against arecording on the ground in laboratory conditions.

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