Orientation-specific Contextual Modulation In Human Visual Cortex
Funder
National Health and Medical Research Council
Funding Amount
$290,413.00
Summary
Context has a strong infuence on our visual perception. We will study patterns of activity in the normal human brain to identify the cortical signature of contextual modulation in vision. The correspondences between patterns of brain activity and visual perception in the normal human brain will provide data against which brain activity in disorders such as schizophrenia and bipolar disorder can be assessed.
Genes And Environment In Late AMD: Pooling A State And Population Resource
Funder
National Health and Medical Research Council
Funding Amount
$701,642.00
Summary
This study will pool cases from the West Australian Macular Degeneration database with the Blue Mountains Eye Study (NSW), to investigate the interplay of genes and environmental factors on risk of age-related macular degeneration (AMD), in particular the late, vision threatening stage. It will provide insights into the underlying causes of AMD, and could allow us to target people with AMD susceptibility genes for preventive approaches, which could reduce the burden of this disease.
Functional Interactions Between Primate Cortical Areas In Tasks Involving Attention And Short-term Memory
Funder
National Health and Medical Research Council
Funding Amount
$267,280.00
Summary
To navigate and operate in the cluttered and dynamic sensory world around us, our brains need to be able to attend to specific objects or features in the environment, identify them and also know where they exist at any one instant of time, prior to performing the appropriate action. The attention, memory, decision and motor components involved in this process possibly involve a variety of cortical areas and neuronal operations. The special primate preparation we have developed permits us to eluc ....To navigate and operate in the cluttered and dynamic sensory world around us, our brains need to be able to attend to specific objects or features in the environment, identify them and also know where they exist at any one instant of time, prior to performing the appropriate action. The attention, memory, decision and motor components involved in this process possibly involve a variety of cortical areas and neuronal operations. The special primate preparation we have developed permits us to elucidate at a neuronal level many of these brain mechanisms. By recording neuronal activities in two different cortical areas simultaneously as the monkey performs a memory task that he has been trained on, we will test the following ideas: (1) A cortical region in the dorsal, parietal stream directs spatial attention by gating other visual areas to process only a selected region of the visual world (2) A region in the ventral, temporal stream directs attention to specific features in the visual world by gating earlier cortical areas (3) The parietal cortical areas that mediate intention for action hold the relevant information in working memory till it is forwarded to the more anterior premotor areas. These experiments have the potential to reveal the basic neuronal scheme that underpins functions such as attention, visual recognition and memory, which are impaired in many neurological disorders.Read moreRead less
Functional Connectivity Between Visual Cortical Areas In The Non-human Primate
Funder
National Health and Medical Research Council
Funding Amount
$387,585.00
Summary
Visual information going from the eyes to the brain is processed in different parts of the brain to extract useful information. However, to be able to select what is important from among the vast number of objects in the scene, top-down signals from higher areas need to act on incoming signals in earlier areas. This project aims to identify what sort of neural pathways are involved in this and how it is done at the cellular level.
Neuronal Linking Of Attention, Perception And Action
Funder
National Health and Medical Research Council
Funding Amount
$586,469.00
Summary
We are able to perceive and interact with the environment around us primarily because a filter of attention selects just the objects or features of relevance in the world and helps to make appropriate motor responses. This project will study how attentional networks of the brain operate to link our perception and action. An understanding of this process is fundamental to revealing the underlying pathology in many neurological conditions where attention is impaired.
Interactions Between Afferent Channels In Vision: Basic Neurophysiology And Implications For The Pathology Of Dyslexia
Funder
National Health and Medical Research Council
Funding Amount
$423,662.00
Summary
We intend to study the interactions between different information channels in the primate visual system. The pathways from the eyes to the brain consist of different types of nerve fibres carrying distinct sorts of information. These channels have been believed to remain separate as they transmit the information through various levels of the brain. Finally, in the neocortex, it has been suggested that the visual information goes along two major streams, one dorsally to the parietal cortex and th ....We intend to study the interactions between different information channels in the primate visual system. The pathways from the eyes to the brain consist of different types of nerve fibres carrying distinct sorts of information. These channels have been believed to remain separate as they transmit the information through various levels of the brain. Finally, in the neocortex, it has been suggested that the visual information goes along two major streams, one dorsally to the parietal cortex and the other ventrally to the temporal cortex. Based upon recent studies, we question this strict segregation of the pathways and propose to study how interactions occur between the two streams and whether the two channels do come together at early levels of the visual pathway. We will also test our idea whether, of the dorsal and ventral streams, one stream might actually gate the other and decide what goes through the other stream. In fact, from our own recent studies, we have reason to believe that the way our attentional system might operate to select salient aspects of the visual scene may be through the dorsal stream selecting what goes into the ventral stream, which seems to be responsible for identifying objects. In the proposed project we will test this idea rigorously. From various lines of evidence, we also argue that the neural mechanisms that underlie this attentional spotlight is exploited by human children when they learn to read. It follows that any defect in the dorsal pathway or in the fibres and cells that feed into this will cause difficulties in reading. We believe this to be the underlying problem in dyslexic children. The project will undertake a number of experiments to test this idea.Read moreRead less
The human brain has many subdivisions (�areas�) that are dedicated to vision, but in many cases their functions remain unclear. This project will study an area located deep in the brain, about which very little is known, and which appears to be affected from early stages in conditions such as Alzheimer�s disease. By understanding the patterns of electrical activity of cells in this region, and their connections with other brain areas, we hope to decipher their contribution to sensory cognition.