Distraction by deviant sounds: disgusting and neutral words capture attention to the same extent

Several studies have argued that words evoking negative emotions, such as disgust, grab attention more than neutral words, and leave traces in memory that are more persistent. However, these conclusions are typically based on tasks requiring participants to process the semantic content of these words in a voluntarily manner. We sought to compare the involuntary attention grabbing power of disgusting and neutral words using them as rare and unexpected auditory distractors in a cross-modal oddball task, and then probing the participants’ memory for these stimuli in a surprise recognition task. Frequentist and Bayesian analyses converged to show that, compared to a standard tone, disgusting and neutral auditory words produced significant but equivalent levels of distraction in a visual categorization task, that they elicited comparable levels of memory discriminability in the incidental recognition task, and that the participants’ individual sensitivity to disgust did not influence the results. Our results suggest that distraction by unexpected words is not modulated by their emotional valence, at least when these words are task-irrelevant and are temporally and perceptually decoupled from the target stimuli.

Increment and decrement tone frequency effects in English-speaking adults

Mismatch negativity (MMN) has been shown to vary in amplitude and latency depending on deviance magnitude. However, how tone deviance direction affects its generation is poorly understood due to paucity of data. The present study sought to determine whether increment and decrement frequencies with deviance magnitudes of 20, 40, and 50 Hz yield differential MMN responses. English-speaking adults were presented two sets of standard and deviant pure tones in a passive event-related potential (ERP) oddball paradigm. Both stimulus sets had the same standard tone of 200 Hz. Each standard tone was accompanied by a set of either increment or decrement deviant tones. The increment tones were 220, 240, and 250 Hz, and the decrement tones were 180, 160, and 150 Hz. Thus, regardless of direction, deviance magnitudes were kept the same at 20 Hz, 40 Hz, and 50 Hz across each stimulus set. Results showed that ERP amplitudes varied according to deviance direction. Decrement stimuli of 160 Hz and 150 Hz elicited larger MMN responses than their corresponding increment stimuli (240 Hz and 150 Hz). These outcomes are consistent with data that indicate that the perception of low and high pitch is mediated by differential discrimination thresholds.

Implicit temporal predictability biases slow oscillatory phase in auditory cortex and enhances pitch discrimination sensitivity

Can human listeners use strictly implicit temporal contingencies in auditory input to form temporal predictions, and if so, how are these predictions represented endogenously? To assess this question, we implicitly manipulated foreperiods in an auditory pitch discrimination task. Unbeknownst to participants, the pitch of the standard tone could either be deterministically predictive of the onset of the target tone, or convey no predictive information. Both conditions were presented interleaved in one stream, and separated by variable inter-stimulus intervals such that there was no dominant stimulus rhythm throughout. Even though participants were unaware of the implicit temporal contingencies, pitch discrimination sensitivity (i.e. the slope of the psychometric function) increased when the onset of the target tone was predictable in time (N = 49). Concurrently recorded EEG data (N = 24) revealed that standard tones which initiated temporal predictions evoked a more negative N1 component than non-predictive standards, and were followed by an increase in delta power during the foreperiod. Furthermore, the phase angle of delta oscillations (1–3Hz) evoked by the standard tone predicted pitch discrimination sensitivity at the target tone (1.75 s later on average), which suggests that temporal predictions can be initiated by an optimized delta phase reset. In sum, we show that auditory perception benefits from implicit temporal contingencies, and provide evidence for a role of slow neural oscillations in the endogenous representation of temporal predictions, in absence of exogenously driven entrainment to rhythmic input.Significance StatementTemporal contingencies are ubiquitous in sensory environments, especially in the auditory domain, and have been shown to facilitate perception and action. Yet, how these contingencies in exogenous inputs are transformed into an endogenous representation of temporal predictions is not known. Here, we implicitly induced temporal predictability in the absence of a rhythmic input structure, that is without exogenously driven entrainment of neural oscillations. Our results show that even implicit and non-rhythmic temporal predictions are extracted and used by human observers, underlining the role of timing in sensory processing. Furthermore, our EEG results point towards an instrumental role of delta oscillations in initiating temporal predictions by an optimized phase reset in response to a temporally predictive cue.

Proactive Interference of Differently Ordered Tone Sequences with the Accuracy and Speed of Two-Tone Frequency Comparisons

Participants judged the direction of the frequency difference between a standard tone and a comparison tone separated by a silent interval and preceded by a series of three interfering tones. The frequencies of the interfering tones were all either lower/higher than (providing interference) or the same as (providing no interference) the standard-tone frequency. When providing interference, the interfering tones were further ordered either randomly or so that they formed melodically ascending/ descending sequences toward the standard-tone frequency. Irrespective of the order of the interfering tones, the judgments were more accurate when the interfering tones and the comparison tone deviated in frequency in the opposite, rather than the same, direction from the standard tone. Reaction times of these judgments were in line with the data based on the judgment accuracy. The results suggest that the representations of individual interfering tones, and not of anticipations extrapolated from them as a compound, were involved in proactive interference with frequency-comparison performance.

The Nature of Preattentive Storage in the Auditory System

Event-related potentials were recorded to tones that subjects ignored while reading a book of their choosing. In all conditions, 90% of the tones were 100 msec in duration and 10% of the tones were 170 msec in duration. In a control condition, a customary oddball paradigm was used in which all of the tones were identical except for the longer duration tones. In two conditions, the tones varied over a wide range of tonal frequencies from 700 to 2050 Hz in 10 steps of 150 Hz. In another condition, the tones varied over the same frequencies but also varied in intensity from about 60 to 87 dB in steps of 3 dB. Thus, there was no “standard” tone in the sense of a frequently presented tone that had identical stimulus features. A mismatch negativity (MMN) was elicited in all conditions. The data are discussed in terms of the storage of information in the memory upon which the MMN is based.

Pitch versus Brightness of Timbre: Detecting Combined Shifts in Fundamental and Formant Frequency

The pitch of a periodic tone depends on its fundamental frequency (F0), and the brightness of its timbre depends on the centroid of its power spectrum (Fc). The goal of the present study was to determine whether small shifts in F0 and in Fc are detected independently of each other. The standard tone used had an F0 of 400 Hz, five harmonics (400-2000 Hz), and a triangular spectral envelope peaking at an Fc of 1000 Hz. With a forced-choice adaptive procedure, detection thresholds were measured for (1) shifts in F0 alone (Fc being fixed), (2) shifts in Fc alone (F0 being fixed), and (3) combined shifts in F0 and Fc. The two components of the combined shifts were chosen to have the same level of detectability when presented alone. Overall, as expected from the independence model, the combined shifts were not better detected when their two components had the same direction (F0 and Fc both increase, or both decrease) than when they had opposite directions. However, substantial differences between subjects were observed with respect to the perceptual integration of shifts in F0 and in Fc.

Tonality, Tonal Scheme, and Contour in Delayed Recognition of Tone Sequences

Two experiments were conducted to test Bartlett and Dowling's conclusion (1980) that the key of a tone sequence strongly influences recognition for short retention intervals, that the influence decreases with increasing retention time, and that the importance of the melodic interval information increases during the retention interval. Five different retention times were used (1,5,8,15, and 30 sec), together with standard tone sequences with a clear tonal scheme and two different contours (two or four directional contour changes). Subjects with moderate musical experience were able to discriminate tonal imitations and transpositions of the standards at all retention times; the number of contour changes did not influence the responses. It was concluded that interval information can be extracted from sequences with strong cues for a particular key within a very short period of time and that one of the major dimensions of tone sequences is not tonality or nontonality, but rather the degree of tonal clarity. This characteristic even may be superior to the number of contour changes.

Variability in Matches to Subjective Tinnitus

For patients with noise-induce sensorineural hearing loss, the results of matching a binaurally presented comparison tone to subjective tinnitus during a 20-days test period are reported. As a control, results of matching an external comparison tom, to a standard tone. are also presented. The variability for tinnitus measurements was extremely large relative to comparable measures for a objective stimuli The relevance of this finding to the nature of tinnitus and to the construction of tinnitus maskers is discussed.

Diplacusis Associated with Bilateral High Frequency Hearing Loss

Seven normal-hearing subjects and seven subjects with mild bilateral high-frequency sensorineural hearing losses were studied to explore the presence of diplacusis. A tracking procedure of psychophysical method of adjustment-limits was used for pitch judgments rather than the traditional method of adjustment. Each subject was presented with a standard 4000-Hz tone for 500 msec and alternately a variable tone for 500 msec. Subjects were instructed to adjust the variable tone upward or downward in pitch to bracket the pitch sensation of the standard tone. Two intra-aural and two interaural listening conditions were studied. A graphic representation of the subjects' adjustments of the variable tone was obtained for each condition. The resulting tracing indicated frequency correlates to the pitch adjustments from which excursion width and constant error were calculated. Some hard-of-hearing subjects and one normal-hearing subject were found to have diplacusis. Subjects with hearing losses exhibited larger excursion widths for intra- and interaural listening conditions. Subjects with hearing losses tended to be less consistent in pitch judgments than normal-hearing subjects. These findings were interpreted to mean that bilaterally symmetrical hearing losses increase the incidence of pitch aberrations.