Blood Plasma Hormone-Level Influence on Vocal Function.

Purpose This preliminary study examined the influence of menstrual cycle phase and hormone levels on acoustic measurements of vocal function in reproductive and postmenopausal females. Mean fundamental frequency (f0), speaking fundamental frequency (Sf0), and cepstral peak prominence (CPP) were evaluated. It was hypothesized that Sf0 and CPP would be lower during the luteal and ischemic phases of the menstrual cycle. Group differences with lower values in postmenopausal females and greater variability in the reproductive females were also hypothesized. Method A mixed factorial analysis of variance was used to examine differences between reproductive and postmenopausal females and the four phases of the menstrual cycle. Separate analyses of variances were implemented for each of the dependent measures. Twenty-eight female participants (15 reproductive cycling, 13 postmenopausal) completed the study. Participants were recorded reading the Rainbow Passage and sustaining the vowel /a/. Mean vocal f0, Sf0, and CPP were determined from the acoustic samples. Blood assays were used to determine estrogen, progesterone, testosterone, and neuropeptide Y levels at four data collection time points. Results Group differences in hormone levels and Sf0 values were established with the postmenopausal group having significantly lower hormone levels and significantly lower Sf0 than the reproductive cycling group across the phases. Analysis of the reproductive group by hormone levels and cycle phase revealed no significant differences for CPP or Sf0 across phases. Higher estrogen was identified in the ovulation phase, and higher progesterone was identified in the luteal phase. Conclusions Significant differences in hormone levels and Sf0 were identified between groups. Within the reproductive cycling group, the lack of significant difference in acoustic measures relative to hormone levels indicated that the measures taken may not have been sensitive enough to identify hormonally mediated vocal function changes. The participant selection may have biased the findings in that health conditions and medications that are known to influence voice function were used as exclusion criteria.

The ticking time bomb: Using eye-tracking methodology to capture attentional processing during gradual time constraints.

Many decisions are made under suboptimal circumstances, such as time constraints. We examined how different experiences of time constraints affected decision strategies on a probabilistic inference task and whether individual differences in working memory accounted for complex strategy use across different levels of time. To examine information search and attentional processing, we used an interactive eye-tracking paradigm where task information was occluded and only revealed by an eye fixation to a given cell. Our results indicate that although participants change search strategies during the most restricted times, the occurrence of the shift in strategies depends both on how the constraints are applied as well as individual differences in working memory. This suggests that, in situations that require making decisions under time constraints, one can influence performance by being sensitive to working memory and, potentially, by acclimating people to the task time gradually.

Implications of cognitive load for hypothesis generation and probability judgment.

We tested the predictions of HyGene (Thomas et al., 2008) that both divided attention at encoding and judgment should affect the degree to which participants' probability judgments violate the principle of additivity. In two experiments, we showed that divided attention during judgment leads to an increase in subadditivity, suggesting that the comparison process for probability judgments is capacity limited. Contrary to the predictions of HyGene, a third experiment revealed that divided attention during encoding leads to an increase in later probability judgment made under full attention. The effect of divided attention during encoding on judgment was completely mediated by the number of hypotheses participants generated, indicating that limitations in both encoding and recall can cascade into biases in judgments.

Decision moving window: using interactive eye tracking to examine decision processes.

It has become increasingly more important for researchers to better capture the complexities of making a decision. To better measure cognitive processes such as attention during decision making, we introduce a new methodology: the decision moving window, which capitalizes on both mouse-tracing and eye-tracking methods. We demonstrate the effectiveness of this methodology in a probabilistic inferential decision task where we reliably measure attentional processing during decision making while allowing the person to determine how information is acquired. We outline the advantages of this methodological paradigm and how it can advance both decision-making research and the development of new metrics to capture cognitive processes in complex tasks.

Taxing executive processes does not necessarily increase impulsive decision making.

A link has been established between impulsivity in real-world situations and impulsive decision making in laboratory tasks in brain-damaged patients and individuals with substance abuse. Whether or not this link exists for all individuals is less clear. We conducted an experiment to determine whether taxing central executive processes with a demanding cognitive load task results in impulsive decision making in a normal sample. Participants (n = 53) completed a delay discounting task under the presence (load condition) and absence (control condition) of a demanding generation task. Results indicated that taxing working memory is neither necessary nor sufficient to produce impulsive decision making; instead, the demanding generation task resulted in an increase in the number of inconsistent choices.

Psychological plausibility of the theory of probabilistic mental models and the fast and frugal heuristics.

The theory of probabilistic mental models (PMM; G. Gigerenzer, U. Hoffrage, & H. Kleinbölting, 1991) has had a major influence on the field of judgment and decision making, with the most recent important modifications to PMM theory being the identification of several fast and frugal heuristics (G. Gigerenzer & D. G. Goldstein, 1996). These heuristics were purported to provide psychologically plausible cognitive process models that describe a variety of judgment behavior. In this article, the authors evaluate the psychological plausibility of the assumptions upon which PMM were built and, consequently, the psychological plausibility of several of the fast and frugal heuristics. The authors argue that many of PMM theory's assumptions are questionable, given available data, and that fast and frugal heuristics are, in fact, psychologically implausible.

Word concreteness and encoding effects on context-dependent discrimination.

In three experiments, we investigated the effects of word concreteness and encoding instructions on context-dependent discrimination in verbal contexts, using Murnane, Phelps, and Malmberg's (1999) ICE (item, context, ensemble) theory as the framework Word concreteness was manipulated within participants, and encoding was manipulated between participants. It was hypothesized that the magnitude of context-dependent discrimination would be affected by both concreteness and encoding instructions. Imagery instructions resulted in context-dependent discrimination for both concrete and abstract word pairs across all the experiments. Context-dependent discrimination was observed under rote instructions for concrete and abstract words, particularly when the same context word was paired multiple times with the targets. The results indicated that context-dependent discrimination is not dependent solely on the use of interactive imagery instructions or on word concreteness.

Does working memory load lead to greater impulsivity? Commentary on Hinson, Jameson, and Whitney (2003).

Previous research by J. M. Hinson, T. L. Jameson, and P. Whitney (2003) demonstrated that a secondary task in a delayed discounting paradigm increased subjects' preference for the immediate reward. J. M. Hinson et al. interpreted their findings as evidence that working memory load results in greater impulsivity. The present authors conducted a reanalysis of the data from J. M. Hinson et al.'s Experiment 1 at the individual-subject level. Difference scores were calculated by subtracting the digit memory load condition from the control condition for k (discounting parameter) and a measure of "erroneous" responses. The results indicated that the secondary task increased random responding, which in turn can account for the increased mean estimates of k. Thus, the data do not support the claim that cognitive load affects impulsivity per se.

Reducing bias in frequency judgment by improving source monitoring.

A common finding in judgment and decision making is that people's frequency judgments often fail to map onto objective frequencies. The present research examined the possibility that one source of bias in frequency judgment is attributable to people's inability to screen out irrelevant memory traces. We used a two-list source-monitoring paradigm to investigate whether frequency judgments are influenced by "extra-experimental" experiences and whether enhancing source monitoring improves judgment accuracy. Across four experiments we found: (1) frequency judgments regarding one list were biased by the second, (2) manipulating encoding between lists improved source monitoring and resulted in more accurate judgments, (3) manipulating item context between lists improved source monitoring and resulted in more accurate judgments, but only when the context was item specific, and (4) manipulating simple-background context between lists was ineffective at improving source monitoring.