Social and Behavioral Sciences Commons^™

Examining Age-Related Enhancement Of Multisensory Gain: The Role Of Sensory Decline And Inverse Effectiveness, Laura C. Schneeberger

Electronic Thesis and Dissertation Repository

Older adults experience a greater benefit from multisensory integration than their younger counterparts, but it is unclear why. One hypothesis is that age-related sensory decline weakens unisensory stimulus effectiveness, producing a boost in multisensory gain through inverse effectiveness. Many previous studies present stimuli at the same intensity for both younger and older adults (i.e., stimulus-matched), as opposed to accounting for each participant’s unique perceptual ability (i.e., perception-matched). This makes it difficult to discern the source of age-related differences in multisensory gain. Through a combination of stimulus-matched and perception-matched tasks, I found that older adults exhibit enhanced multisensory gain at low …

Seeing With Sound: Investigating The Behavioural Applications And Neural Correlates Of Human Echolocation, Jennifer L. Milne

Electronic Thesis and Dissertation Repository

Some blind humans use the reflected echoes from self-produced signals to perceive their silent surroundings. Although the use of echolocation is well documented in animals such as bats and dolphins, comparatively little is known about human echolocation. The overarching goal of the work presented in this thesis was to shed light on some of the basic functions of human echolocation, including the perception of the shape, size, and material. I addressed these aspects of echolocation using behavioural psychophysics and neuroimaging.

In Chapter 2 I show that blind echolocators were able to accurately identify the shape of 2D objects, but that …

Are Visual Texture-Selective Areas Recruited During Haptic Texture Discrimination?, Samantha K. Podrebarac

Electronic Thesis and Dissertation Repository

Shape and texture provide cues to object identity, both when objects are explored using vision and via touch (haptics). Visual shape information is processed within the lateral occipital complex (LOC), while texture is processed in medial regions of the collateral sulcus (CoS). Evidence indicates that the LOC is consistently recruited during both visual and haptic shape processing. We used functional magnetic resonance imaging (fMRI) to examine whether 'visual' texture-selective areas are similarly recruited when observers discriminate texture via touch. We used a blocked design in which participants attended to either the texture or shape of a number of 3-dimensional (3D) …