Directing Attention to Locations and to Sensory Modalities: Multiple Levels of Selective Processing revealed with PET

Numerous studies have demonstrated effects of spatial attention within single sensory modalities (within-modal spatial attention) and the effect of directing attention to one sense compared with the other senses (intermodal attention) on cortical neuronal activity. Furthermore, recent studies have been revealing that the effects of spatial attention directed to a certain location in a certain sense spread to the other senses at the same location in space (cross-modal spatial attention). The present study used magnetoencephalography to examine the temporal dynamics of the effects of within-modal and cross-modal spatial and intermodal attention on cortical processes responsive to visual stimuli. Visual or tactile stimuli were randomly presented on the left or right side at a random interstimulus interval and subjects directed attention to the left or right when vision or touch was a task-relevant modality. Sensor-space analysis showed that a response around the occipitotemporal region at around 150 ms after visual stimulation was significantly enhanced by within-modal, cross-modal spatial, and intermodal attention. A later response over the right frontal region at around 200 ms was enhanced by within-modal spatial and intermodal attention, but not by cross-modal spatial attention. These effects were estimated to originate from the occipitotemporal and lateral frontal areas, respectively. Thus the results suggest different spatiotemporal dynamics of neural representations of cross-modal attention and intermodal or within-modal attention.

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Serotonergic modulation across sensory modalities

Journal of Neurophysiology ◽

10.1152/jn.00034.2020 ◽

2020 ◽

Vol 123 (6) ◽

pp. 2406-2425

Author(s):

Tyler R. Sizemore ◽

Laura M. Hurley ◽

Andrew M. Dacks

Keyword(s):

Serotonin Receptor ◽

Physiological State ◽

Sensory Information ◽

Specific Stimulus ◽

Sensory Organization ◽

Sensory Modalities ◽

Multiple Levels ◽

Stimulus Features ◽

Ubiquitous Presence ◽

Serotonergic Modulation

The serotonergic system has been widely studied across animal taxa and different functional networks. This modulatory system is therefore well positioned to compare the consequences of neuromodulation for sensory processing across species and modalities at multiple levels of sensory organization. Serotonergic neurons that innervate sensory networks often bidirectionally exchange information with these networks but also receive input representative of motor events or motivational state. This convergence of information supports serotonin’s capacity for contextualizing sensory information according to the animal’s physiological state and external events. At the level of sensory circuitry, serotonin can have variable effects due to differential projections across specific sensory subregions, as well as differential serotonin receptor type expression within those subregions. Functionally, this infrastructure may gate or filter sensory inputs to emphasize specific stimulus features or select among different streams of information. The near-ubiquitous presence of serotonin and other neuromodulators within sensory regions, coupled with their strong effects on stimulus representation, suggests that these signaling pathways should be considered integral components of sensory systems.

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The availability versus the use of partial information: Multiple levels of selective processing between perception and action

Acta Psychologica ◽

10.1016/0001-6918(95)00038-v ◽

1995 ◽

Vol 90 (1-3) ◽

pp. 145-162 ◽

Cited By ~ 8

Author(s):

Henderikus G.O.M. Smid ◽

Gijsbertus Mulder

Keyword(s):

Perception And Action ◽

Partial Information ◽

Selective Processing ◽

Multiple Levels

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Particle characterization of CVD tungsten metallization for 64 MBIT DRAM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088798 ◽

1991 ◽

Vol 49 ◽

pp. 896-897

Author(s):

Marylyn Bennett-Lilley ◽

Thomas T.H. Fu ◽

David D. Yin ◽

R. Allen Bowling

Keyword(s):

Chemical Vapor ◽

Device Performance ◽

Particle Characterization ◽

Particle Generation ◽

Tungsten Hexafluoride ◽

Homogeneous Particle ◽

Multiple Levels ◽

Circuit Density ◽

Sources Of Contamination

Chemical Vapor Deposition (CVD) tungsten metallization is used to increase VLSI device performance due to its low resistivity, and improved reliability over other metallization schemes. Because of its conformal nature as a blanket film, CVD-W has been adapted to multiple levels of metal which increases circuit density. It has been used to fabricate 16 MBIT DRAM technology in a manufacturing environment, and is the metallization for 64 MBIT DRAM technology currently under development. In this work, we investigate some sources of contamination. One possible source of contamination is impurities in the feed tungsten hexafluoride (WF6) gas. Another is particle generation from the various reactor components. Another generation source is homogeneous particle generation of particles from the WF6 gas itself. The purpose of this work is to investigate and analyze CVD-W process-generated particles, and establish a particle characterization methodology.

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Reaction Time and Brain Waves in Omitted Stimulus Tasks

Journal of Psychophysiology ◽

10.1027/0269-8803/a000001 ◽

2010 ◽

Vol 24 (1) ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Oscar H. Hernández ◽

Muriel Vogel-Sprott

Keyword(s):

Reaction Time ◽

Cognitive Processes ◽

Young Male ◽

Event Related Potential ◽

Auditory Stimuli ◽

Motor Action ◽

Cognitive Component ◽

Sensory Modalities ◽

Two Measures ◽

Somatosensory Stimuli

A missing stimulus task requires an immediate response to the omission of a regular recurrent stimulus. The task evokes a subclass of event-related potential known as omitted stimulus potential (OSP), which reflects some cognitive processes such as expectancy. The behavioral response to a missing stimulus is referred to as omitted stimulus reaction time (RT). This total RT measure is known to include cognitive and motor components. The cognitive component (premotor RT) is measured by the time from the missing stimulus until the onset of motor action. The motor RT component is measured by the time from the onset of muscle action until the completion of the response. Previous research showed that RT is faster to auditory than to visual stimuli, and that the premotor of RT to a missing auditory stimulus is correlated with the duration of an OSP. Although this observation suggests that similar cognitive processes might underlie these two measures, no research has tested this possibility. If similar cognitive processes are involved in the premotor RT and OSP duration, these two measures should be correlated in visual and somatosensory modalities, and the premotor RT to missing auditory stimuli should be fastest. This hypothesis was tested in 17 young male volunteers who performed a missing stimulus task, who were presented with trains of auditory, visual, and somatosensory stimuli and the OSP and RT measures were recorded. The results showed that premotor RT and OSP duration were consistently related, and that both measures were shorter with respect to auditory stimuli than to visual or somatosensory stimuli. This provides the first evidence that the premotor RT is related to an attribute of the OSP in all three sensory modalities.

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