|
Research
My research in cognitive
science examines empirical questions from various theoretical and methodological
perspectives. My work has been profiled by National Public Radio, The
Washington Post, The BBC, and is also referenced in several perception
textbooks (e.g., Coren, Ward, & Enns, 1999; Schiffman, 2000, Sekuler
& Blake, 2006) and an evolutionary psychology text (Buss, 2004). Below
is an overview of some specific areas of investigation.
Evolution and Human
Behavior: My work in auditory motion perception has shown that listeners
perceive looming sound sources as closer than they actually are. My continuing
work is using perceptual tasks, physiological measures, and comparative
techniques and suggests that the bias for looming sounds and systematic
underestimation of arrival time may be an evolved behavioral characteristic.
Other work has examined sex differences in the cortical activation of parents
in response to infant vocalizations. Both lines of work underscore the role
of evolution in shaping behavioral responses.
Comparative Cognition: Recent collaborative work with Asif Ghazanfar
at Princeton examines the perception and multisensory integration of looming
objects in Rhesus monkeys. Our findings support an evolutionary "error
management theory" in the perception of both auditory and visual
looming perception.
Spatial Cognition in Navigation: The perception of space is crucial
to behaviors as diverse as traversing terrain, landing aircraft, or catching
prey. These navigational abilities are informed by both vision and audition.
Thus, an organism must have some means of combining these distinct sources
of information to form a unified representation of external space. A research
goal is to specify ways in which multi-sensory integration and cognitive
representation of external space influence navigation.
Brain Imaging and Auditory Perception: A collaborative relationship
with Erich Seifritz at the University of Bern in Switzerland has provided
me with the opportunity to examine specific patterns of cortical activation
in response to various types of acoustic signals. Our current line of
investigation demonstrates a robust asymmetry in the activation of cortical
areas in response to approaching versus receding sound sources.
Change Deafnessand Voice Identification: These lines of research
grew from student projects and demonstrated a bias for increased pitch
in the identification of unfamiliar voices. Another ongoing project uses
the visual "change blindness" paradigm in the auditory domain.
Musical Expertise: This line of research also stems from student
initiated projects and shows that musical experts and novices scale frequency
change differently. Musical novices assign a lesser amount of dimensional
change to changing frequency than do musical experts. Current experiments
are examining this effect in a developmental context.
Selective Attention to Pitch and Loudness: Historically, auditory
pitch has been considered to be primarily a function of acoustic frequency,
with only a small effect being due to absolute intensity. My recent work
suggests that the dynamic interaction of pitch and loudness (i) occurs
centrally in the auditory system; (ii) is an analytic rather than holistic
process; (iii) has evolved to take advantage of naturally occurring covariation
of frequency and intensity; and (iv) reflects a shortcoming of traditional
static models of loudness perception in a dynamic natural setting.
Applied Cognition, Human-Computer Interaction, and Auditory Display: Auditory
display is the use of non-speech sound to present information. My work
shows that perceptual distortions that occur when dimensions of sound
undergo dynamic change. Dynamic changes in frequency, intensity, and spectral
content are likely vehicles for auditory display. My continuing work shows
that these distortions can be particularly important in the development
of auditory virtual environments and computer workstations.
|