Finding tau rhythms in EEG: An independent component analysis approach.

Tau rhythms are largely defined by sound responsive alpha band (~8-13 Hz) oscillations generated largely within auditory areas of the superior temporal gyri. Studies of tau have mostly employed magnetoencephalography or intracranial recording because of tau's elusiveness in the electroencephalogram. Here, we demonstrate that independent component analysis (ICA) decomposition can be an effective way to identify tau sources and study tau source activities in EEG recordings.

Not fully remembered, but not forgotten: interfering sounds worsen but do not eliminate the representation of pitch in working memory.

Recent research has begun measuring auditory working memory with a continuous adjustment task in which listeners adjust attributes of a sound to match a stimulus presented earlier. This approach captures auditory memory's continuous nature better than standard change detection paradigms that collect binary ("same or different") memory measurements. In two experiments, we assessed the impact of different interference stimuli (multitone complexes vs.

Late ERP correlates of confidence for auditory categorization of complex sounds.

Recent research suggests that confidence judgments relate to the quality of early sensory representations and later modality independent processing stages. It is not known whether the nature of this finding might vary based on task and/or stimulus characteristics (e.g.

Learning to detect auditory signals in noise: Active top-down selection and stable change in signal representations.

Training can improve detection of auditory signals in noise. This learning could potentially occur through active top-down selection mechanisms or stable changes in signal representations. Here, participants were trained and tested (pretest vs.

Effortful listening produces both enhancement and suppression of alpha in the EEG.

Introduction: Adverse listening conditions can drive increased mental effort during listening. Neuromagnetic alpha oscillations (8-13 Hz) may index this , but inconsistencies regarding the direction of the relationship are abundant. We performed source analyses on high-density EEG data collected during a speech-on-speech listening task to address the possibility that opposing alpha power relationships among alpha producing brain sources drive this inconsistency.

EEG power spectral dynamics associated with listening in adverse conditions.

Adverse listening conditions increase the demand on cognitive resources needed for speech comprehension. In an exploratory study, we aimed to identify independent power spectral features in the EEG useful for studying the cognitive processes involved in this effortful listening. Listeners performed the coordinate response measure task with a single-talker masker at a 0-dB signal-to-noise ratio.

Evidence for Age-Equivalent and Task-Dissociative Metacognition in the Memory Domain.

Research suggests that metacognitive monitoring ability does not decline with age. For example, judgments-of-learning (JOL) accuracy is roughly equivalent between younger and older adults. But few studies have asked whether younger and older adults' metacognitive ability varies across different types of memory processes (e.

Effects of auditory training on low-pass filtered speech perception and listening-related cognitive load.

Studies supporting learning-induced reductions in listening-related cognitive load have lacked procedural learning controls, making it difficult to determine the extent to which effects arise from perceptual or procedural learning. Here, listeners were trained in the coordinate response measure (CRM) task under unfiltered (UT) or degraded low-pass filtered (FT) conditions. Improvements in low-pass filtered CRM performance were larger for FT.

Auditory detection learning is accompanied by plasticity in the auditory evoked potential.

Auditory detection can improve with practice. These improvements are often assumed to arise from selective attention processes, but longer-term plasticity as a result of training may also play a role. Here, listeners were trained to detect either an 861-Hz or 1058-Hz tone (counterbalanced across participants) presented in noise at SNRs varying from -10 to -24 dB.

Correction: Artificial neural networks reveal individual differences in metacognitive monitoring of memory.

[This corrects the article DOI: 10.1371/journal.pone.

Artificial neural networks reveal individual differences in metacognitive monitoring of memory.

Previous work supports an age-specific impairment for recognition memory of pairs of words and other stimuli. The present study tested the generalization of an associative deficit across word, name, and nonword stimulus types in younger and older adults. Participants completed associative and item memory tests in one of three stimulus conditions and made metacognitive ratings of perceptions of self-efficacy, task success ("postdictions"), strategy success, task effort, difficulty, fatigue, and stamina.

Easy-to-hard effects in perceptual learning depend upon the degree to which initial trials are "easy".

Starting perceptual training at easy levels before progressing to difficult levels generally produces better learning outcomes than constantly difficult training does. However, little is known about how "easy" these initial levels should be in order to yield easy-to-hard effects. We compared five levels of initial training block difficulty varying from very easy to hard in two auditory-discrimination learning tasks-a frequency modulation rate discrimination (Experiment 1) and a frequency range discrimination (Experiment 2).

Confidence tracks sensory- and decision-related ERP dynamics during auditory detection.

Recent research has focused on measuring neural correlates of metacognitive judgments in decision and post-decision processes during memory retrieval and categorization. However, many tasks (e.g.

I scan, therefore I decline: The time course of difficulty monitoring in humans (homo sapiens) and macaques (macaca mulatta).

The study of nonhumans' metacognitive judgments about trial difficulty has grown into an important comparative literature. However, the potential for associative-learning confounds in this area has left room for behaviorist interpretations that are strongly asserted and hotly debated. This article considers how researchers may be able to observe animals' strategic cognitive processes more clearly by creating temporally extended problems within which associative cues are not always immediately available.

The transfer of category knowledge by macaques (Macaca mulatta) and humans (Homo sapiens).

Cognitive psychologists distinguish implicit, procedural category learning (stimulus-response associations learned outside declarative cognition) from explicit-declarative category learning (conscious category rules). These systems are dissociated by category learning tasks with either a multidimensional, information-integration (II) solution or a unidimensional, rule-based (RB) solution. In the present experiments, humans and two monkeys learned II and RB category tasks fostering implicit and explicit learning, respectively.

Ecology, Fitness, Evolution: New Perspectives on Categorization.

Categorization's great debate has weighed single-system exemplar theory against the possibility of alternative processing systems. We take an evolutionary perspective toward this debate to illuminate it in a new way. Animals are crucial behavioral ambassadors to this area.

Categorization: The View from Animal Cognition.

Exemplar, prototype, and rule theory have organized much of the enormous literature on categorization. From this theoretical foundation have arisen the two primary debates in the literature-the prototype-exemplar debate and the single system-multiple systems debate. We review these theories and debates.

Formal models in animal-metacognition research: the problem of interpreting animals' behavior.

Ongoing research explores whether animals have precursors to metacognition-that is, the capacity to monitor mental states or cognitive processes. Comparative psychologists have tested apes, monkeys, rats, pigeons, and a dolphin using perceptual, memory, foraging, and information-seeking paradigms. The consensus is that some species have a functional analog to human metacognition.

Generalization of category knowledge and dimensional categorization in humans (Homo sapiens) and nonhuman primates (Macaca mulatta).

A theoretical framework within neuroscience distinguishes humans' implicit and explicit systems for category learning. We used a perceptual-categorization paradigm to ask whether nonhumans share elements of these systems. Participants learned categories that foster implicit or explicit categorization in humans, because they had a multidimensional, information-integration (II) solution or a unidimensional, rule-based (RB) solution.

The time course of explicit and implicit categorization.

Contemporary theory in cognitive neuroscience distinguishes, among the processes and utilities that serve categorization, explicit and implicit systems of category learning that learn, respectively, category rules by active hypothesis testing or adaptive behaviors by association and reinforcement. Little is known about the time course of categorization within these systems. Accordingly, the present experiments contrasted tasks that fostered explicit categorization (because they had a one-dimensional, rule-based solution) or implicit categorization (because they had a two-dimensional, information-integration solution).

The interplay between uncertainty monitoring and working memory: Can metacognition become automatic?

The uncertainty response has grounded the study of metacognition in nonhuman animals. Recent research has explored the processes supporting uncertainty monitoring in monkeys. It has revealed that uncertainty responding, in contrast to perceptual responding, depends on significant working memory resources.

Cashing out: The decisional flexibility of uncertainty responses in rhesus macaques (Macaca mulatta) and humans (Homo sapiens).

Researchers are exploring whether animals share with humans something like a metacognitive capacity. Though some results point to human-animal continuities in this domain, they face the dominant criticism that animals' performances might be associative. A persistent problem is that animal-metacognition paradigms present static environments of risk and reward that may foster inflexible and conditioned responding.

Cross-modal information integration in category learning.

An influential theoretical perspective describes an implicit category-learning system that associates regions of perceptual space with response outputs by integrating information preattentionally and predecisionally across multiple stimulus dimensions. In this study, we tested whether this kind of implicit, information-integration category learning is possible across stimulus dimensions lying in different sensory modalities. Humans learned categories composed of conjoint visual-auditory category exemplars comprising a visual component (rectangles varying in the density of contained lit pixels) and an auditory component (in Exp.

Deferred feedback sharply dissociates implicit and explicit category learning.

The controversy over multiple category-learning systems is reminiscent of the controversy over multiple memory systems. Researchers continue to seek paradigms to sharply dissociate explicit category-learning processes (featuring category rules that can be verbalized) from implicit category-learning processes (featuring learned stimulus-response associations that lie outside declarative cognition). We contribute a new dissociative paradigm, adapting the technique of deferred-rearranged reinforcement from comparative psychology.

Decision deadlines and uncertainty monitoring: the effect of time constraints on uncertainty and perceptual responses.

The behavioral uncertainty response has grounded the study of animal metacognition and influenced the study of human psychophysics. However, the interpretation of this response is debated--especially whether it is a behavioral index of metacognition. The authors advanced this interpretation using the dissociative technique of response deadlines.