Current Events

Abstract concept formation was once thought to be a uniquely human ability. An increasing variety of species have shown this ability, however. What determines when an individual will focus on general patterns rather than the particulars of specific events? Does the formation of abstract concepts really require greater cognitive sophistication than other types of associative learning? Recent studies of dogs’ abilities to acquire a repeating concept and a same-different concept suggest that flexible use of abstract concepts may depend on repeated experiences and attentional flexibility.

Computational social scientists have expended a considerable amount of effort in recent years to use models based on distributional semantics (most popularly, word embedding models like BERT and word2vec) to capture the meanings of the words and phrases used to describe people. Existing work tends to focus on evaluating measurements for particular phrases on particular dimensions of meaning (e.g. "how can we measure gender stereotypes of occupational identities?"). But phrases about people exist within a broader, more complex, and less well understood space of meanings.  These analyses thus risk biases in what they are measuring, how they are measuring it, and what claims they make based on those findings. In this talk, I will try to convince you that to address these issues, a new measure of semantic similarity, which I call person-centric similarity, is necessary. In the talk, I will introduce person-centric similarity, why it is necessary, and our current empirical and theoretical work underlying it.

Cochlear implants are devices that provide hearing abilities to individuals with hearing loss who receive little benefit from hearing aids. Many cochlear-implant users benefit substantially from this technology, but hearing is not restored to normal. Instead, cochlear implants provide a highly degraded signal that can be effortful to perceive. Additionally, age-related changes in auditory processing could exacerbate the effort required to process a degraded signal. Pupillometry was used as an index of listening effort in a series of experiments examining the role of signal degradation and age on listening effort. Results suggest that older cochlear-implant users are at risk for high listening effort.

Atypical hemisphericasymmetry: the influence on sensory processingin autismLateralized specialization of the two cerebral hemispheres underlies many cognitive functions and behavioral abilities and is a fundamental structural hallmark of the human brain. Increasing evidenc e suggests that several neurodevelopmental and psychiatricdisorders such as bipolar disorder, schizophrenia, and autism spectrum disorders (ASD) are associated with abnormal patterns of cerebra l lateralization. Abnormal structural and functional lateralization of circuits subserving motor, auditory, somatosensory, visual face processing and language-related functions have been reported in individua ls with autism spectrum disorder. Yet, the neuronal structures and pathophysiological mechanisms underlying these observed cerebral asymmetries in ASD remain unclear.Iwill present our effortsto leveragetwo photon imaging to elucidate developmental mechanisms that maintain the inter and intra hemispheric balance between excitatory and inhibitory (E/I) transmission.I will also discuss implicatio ns ofatypical interhemispheric E/I balance on tactile defensiveness in ASD models.

Difficult listening tasks place increased demand on cognitive resources. The electroencephalogram (EEG) is frequently used to characterize this "listening effort", with theta (~4-8 Hz) and alpha (~8-13 Hz) oscillations proposed as listening effort indices. Two main inconsistencies have been revealed among studies in this area. First, while some report strong positive relationships between listening effort and theta, others have failed to observe theta effects even when effort clearly differs among conditions. Second, effects in the alpha-band can appear as either increases or decreases in oscillatory power. This makes it difficult to make a priori predictions as to the direction of alpha/effort relationships. I will present data showing that theta power tracks working memory demand independently of task difficulty, suggesting that theta oscillations reflect a sub-component of effortful listening. I will then show that increases and decreases in alpha can be seen at the same time during listening. The direction of alpha power modulation depends on the brain source that produces alpha and the attentional states of listeners. Taken together, apparent inconsistencies in the literature are likely related to: 1) a vague conceptualization of listening effort that fails to acknowledge its sub-components, and 2) a failure to recognize that multiple independent sources of EEG oscillations exist within cortex. I will end with the description of some ongoing projects in my lab that are exploring how EEG oscillations relate to specific aspects of effortful listening.