Biomedical subjects

S Soto-Faraco

Publications and source records attributed to S Soto-Faraco.

5 recordsLinked to original sources

PubMed2001

The effects of acoustic mismatch and selective listening on repetition deafness.

Previous research (i.e., M. Miller & D. O. MacKay, 1994, 1996) has suggested that repetition deafness (RD), like repetition blindness, is robust to physical identity and that it consists in a failure to recall specifically the 2nd of the 2 critical targets (C1 and C2). However, some confounds due to memory load and response biases make available evidence inconclusive. Experiment 1 provided a strong test of RD between physically mismatching stimuli using a low memory load methodology. In Experiment 2, the same presentation method was combined with a selective recall task to find that RD is specific of C2. Experiments 3A and 3B showed, through an attentional manipulation, that RD is eliminated when people can successfully ignore C1 but not otherwise. It is argued that present data favor a perceptual interpretation of the RD. Furthermore, the present results support the hypothesis of recognition failure as opposed to the alternative token individuation failure hypothesis.

Analysis of Variance↗

PubMed2001

Failure to remap visuotactile space across the midline in the split-brain.

We examined the effect of posture change on the representation of visuotactile space in a split-brain patient using a cross-modal congruency task. Split-brain patient J.W. made speeded elevation discrimination responses (up versus down) to a series of tactile targets presented to the index finger or thumb of his right hand. We report congruency effects elicited by irrelevant visual distractors placed either close to, or far from, the stimulated hand. These cross-modal congruency effects followed the right hand as it moved within the right hemispace, but failed to do so when the hand crossed the midline into left hemispace. These results support recent claims that interhemispheric connections are required to maintain an accurate representation of visuotactile space.

Attention↗

PubMed2001

Spatial modulation of repetition blindness and repetition deafness.

When two identical visual items are presented in rapid succession, people often fail to report the second instance when trying to recall both (e.g., Kanwisher, 1987). We investigated whether this temporal processing deficit is modulated by the spatial separation between the repeated stimuli within both audition and vision. In Experiment 1, lists of one to three digits were rapidly presented from loudspeaker cones arranged in a semicircle around the participant. Recall accuracy was lower when repeated digits were presented from different positions rather than from the same position, as compared to unrepeated control pairs, demonstrating that auditory repetition deafness (RD) is modulated by the spatial displacement between repeated items. A similar spatial modulation of visual repetition blindness (RB) was reported when pairs of masked letters were presented visually from either the same or different positions arranged on a semicircle around fixation (Experiment 2). These results cannot easily be accounted for by the token individuation hypothesis of RB (Kanwisher, 1987; Park & Kanwisher, 1994) and instead support a recognition failure account (Hochhaus & Johnston, 1996; Luo & Caramazza, 1995, 1996).

Auditory Perception↗

PubMed2000

An auditory repetition deficit under low memory load.

Previous studies of the auditory analogue of repetition blindness have led to different conclusions regarding the nature of the effect (e.g., N. Kanwisher & M. C. Potter, 1989; M. Miller & D. MacKay, 1994). In the present study, recall accuracy for repeated elements was examined with lists of 2 or 3 items presented dichotically under high temporal pressure. When this procedure was used, a repetition deficit in recall was obtained for both vowels (Experiment 1) and consonant-vowel syllables (Experiment 2). Further experiments demonstrated that this deficit decreases as the stimulus onset asynchrony between the 2 critical elements increases (Experiment 3) and showed that the effect also occurs for words and not just nonsense syllables (Experiment 4). In all 4 experiments, estimations of guessing biases showed that responses to unrepeated lists were not artificially favored over responses to repeated lists.

Acoustic Stimulation↗

PubMed1999

Online processing of native and non-native phonemic contrasts in early bilinguals.

There is considerable debate about whether bilinguals can distinguish L2 phonemic contrasts as efficiently as first language speakers can. To test this issue, a group of highly proficient Spanish-dominant Catalan-Spanish bilinguals (who had been exposed to Catalan between the ages of 3 and 4, but who, previous to this age, had been exposed only to Spanish) and another group of Catalan-dominant bilinguals (who had been exposed to Catalan from birth) were compared in a gating task. We developed a variation of the gating procedure that included a two-alternative forced choice test after each fragment was played. The differences between the two alternatives consisted of phonemic contrasts existing in Catalan but not in Spanish. Four contrasts were tested: two vocalic contrasts [symbols: see text] and two consonantal contrasts [symbols: see text]. The results showed that Spanish-dominant bilinguals, even the subset who were able to make correct identifications at the last gate, systematically performed worse than the group of Catalan-dominant bilinguals, needing longer portions of the signal to be able to correctly identify the stimuli. We argue that these results support the hypothesis that L1 shapes the perceptual system at early stages of development in such a way that it will determine the perception of non-native phonemic contrasts, even if there is extensive and early exposure to L2.

Adult↗