The Time-Course of the Cross-Modal Semantic Modulation of Visual Picture Processing by Naturalistic Sounds and Spoken Words

2013 ◽  
Vol 26 (4) ◽  
pp. 371-386 ◽  
Author(s):  
Yi-Chuan Chen ◽  
Charles Spence
Keyword(s):  
Time Course ◽  
Inhibitory Effect ◽  
Stimulus Onset ◽  
Noise Condition ◽  
Semantic Congruency ◽  
Spoken Words ◽  
Processing Pathways ◽  
Time Courses ◽  
Task Irrelevant ◽  
Modal Semantic

The time-course of cross-modal semantic interactions between pictures and either naturalistic sounds or spoken words was compared. Participants performed a speeded picture categorization task while hearing a task-irrelevant auditory stimulus presented at various stimulus onset asynchronies (SOAs) with respect to the visual picture. Both naturalistic sounds and spoken words gave rise to cross-modal semantic congruency effects (i.e., facilitation by semantically congruent sounds and inhibition by semantically incongruent sounds, as compared to a baseline noise condition) when the onset of the sound led that of the picture by 240 ms or more. Both naturalistic sounds and spoken words also gave rise to inhibition irrespective of their semantic congruency when presented within 106 ms of the onset of the picture. The peak of this cross-modal inhibitory effect occurred earlier for spoken words than for naturalistic sounds. These results therefore demonstrate that the semantic priming of visual picture categorization by auditory stimuli only occurs when the onset of the sound precedes that of the visual stimulus. The different time-courses observed for naturalistic sounds and spoken words likely reflect the different processing pathways to access the relevant semantic representations.

Inhibition of Steady-State Smooth Pursuit and Catch-Up Saccades by Abrupt Visual and Auditory Onsets

2010 ◽  
Vol 104 (5) ◽  
pp. 2573-2585 ◽  
Author(s):  
Dirk Kerzel ◽  
Sabine Born ◽  
David Souto
Keyword(s):  
Steady State ◽  
Inhibitory Effect ◽  
Stimulus Onset ◽  
Subcortical Structures ◽  
Motion Direction ◽  
Irrelevant Sound ◽  
Long Latency ◽  
Catch Up ◽  
Task Irrelevant ◽  
Pursuit Gain

It is known that visual transients prolong saccadic latency and reduce saccadic frequency. The latter effect was attributed to subcortical structures because it occurred only 60–70 ms after stimulus onset. We examined the effects of large task-irrelevant transients on steady-state pursuit and the generation of catch-up saccades. Two screen-wide stripes of equal contrast (4, 20, or 100%) were briefly flashed at equal eccentricities (3, 6, or 12°) from the pursuit target. About 100 ms after flash onset, we observed that pursuit gain dropped by 6–12% and catch-up saccades were entirely suppressed. The relatively long latency of the inhibition suggests that it results from cortical mechanisms that may act by promoting fixation or the deployment of attention over the visual field. In addition, we show that a loud irrelevant sound is able to generate the same inhibition of saccades as visual transients, whereas it only induces a weak modulation of pursuit gain, indicating a privileged access of acoustic information to the saccadic system. Finally, irrelevant changes in motion direction orthogonal to pursuit had a smaller and later inhibitory effect.

The effect of task-irrelevant stimulus ‘graspability’ on reaching actions

2012 ◽  
Vol 25 (0) ◽  
pp. 99
Author(s):  
Samuel Couth ◽  
Ellen Poliakoff ◽  
Emma Gowen
Keyword(s):  
Reaction Times ◽  
Irrelevant Stimulus ◽  
Inhibitory Effect ◽  
Stimulus Onset ◽  
Reaching Movement ◽  
Visual Spatial ◽  
Onset Delay ◽  
Task Irrelevant ◽  
And Control ◽  
Previous Reaction

Reaching and grasping requires integration of visual, proprioceptive and somatosensory inputs. Previous research has shown that manipulating the ‘graspabilty’ of a visual stimulus influences reaction times to that stimulus (e.g., Tucker and Ellis, 1998). Here we explored whether this same effect can be extended to the planning and online control of arm movements. Participants made a mimed reaching movement with their left or right hand depending on the colour of images of affordance (door handles) and control stimuli (a row of dots of similar size and orientation as the door handle). Stimulus onset was manipulated by changing when the grey stimulus changed colour. Stimuli either pointed towards (compatible) or pointed away from (incompatible) the responding hand. Spatially compatible affordance stimuli facilitated reach onset compared to other stimuli and compatibility combinations, replicating previous reaction time studies. This can be attributed to a priming of the motor system by spatially compatible affording items. Results also indicated a larger outwards deviation of reach trajectory for spatially incompatible control stimuli compared to spatially compatible control stimuli, which waned with stimulus onset delay. This reveals an immediate inhibitory effect on reach trajectory, such that outwards movement is over-compensated to negate this incompatible orientation. Overall, we observed that the effect of visual spatial compatibility on reach kinematics differs with the action relevance of the stimulus. We are currently exploring how this multisensory visuomotor effect changes with age.

scholarly journals Early information processing contributions to object individuation revealed by perception of illusory figures

2016 ◽  
Vol 116 (6) ◽  
pp. 2513-2522 ◽  
Author(s):  
Claire K. Naughtin ◽  
Jason B. Mattingley ◽  
Paul E. Dux
Keyword(s):  
Information Processing ◽  
Time Course ◽  
Empirical Work ◽  
Event Related Potentials ◽  
Stimulus Onset ◽  
Processing Stage ◽  
Object Individuation ◽  
Related Potentials ◽  
Physical Elements ◽  
Task Irrelevant

To isolate multiple coherent objects from their surrounds, each object must be represented as a stable perceptual entity across both time and space. Recent theoretical and empirical work has proposed that this process of object individuation is a mid-level operation that emerges around 200–300 ms after stimulus onset. However, this hypothesis is based on paradigms that have potentially obscured earlier effects. Furthermore, no study to date has directly assessed whether object individuation occurs for task-irrelevant objects. In the present study we used electroencephalography (EEG) to measure the time course of individuation, for stimuli both within and outside the focus of attention, to assess the information processing stage at which object individuation arises for both types of objects. We developed a novel paradigm involving items defined by illusory contours, which allowed us to vary the number of to-be-individuated objects while holding the physical elements of the display constant (a design characteristic not present in earlier work). As early as 100 ms after stimulus onset, event-related potentials tracked the number of objects in the attended hemifield, but not those in the unattended hemifield. By contrast, both attended and unattended objects could be individuated at a later stage. Our findings challenge recent conceptualizations of the time course of object individuation and suggest that this process arises earlier for attended than unattended items, implying that voluntary spatial attention influences the time course of this operation.

scholarly journals Pseudo-streaming potentials in Necturus gallbladder epithelium. II. The mechanism is a junctional diffusion potential.

1992 ◽  
Vol 99 (3) ◽  
pp. 317-338 ◽  
Author(s):  
L Reuss ◽  
B Simon ◽  
C U Cotton
Keyword(s):  
Time Course ◽  
Bathing Solution ◽  
Intercellular Spaces ◽  
Similar Time ◽  
Streaming Potentials ◽  
Osmotic Water ◽  
Lateral Intercellular Spaces ◽  
Transepithelial Voltage ◽  
Time Courses ◽  
Good Agreement

The mechanisms of apparent streaming potentials elicited across Necturus gallbladder epithelium by addition or removal of sucrose from the apical bathing solution were studied by assessing the time courses of: (a) the change in transepithelial voltage (Vms). (b) the change in osmolality at the cell surface (estimated with a tetrabutylammonium [TBA+]-selective microelectrode, using TBA+ as a tracer for sucrose), and (c) the change in cell impermeant solute concentration ([TMA+]i, measured with an intracellular double-barrel TMA(+)-selective microelectrode after loading the cells with TMA+ by transient permeabilization with nystatin). For both sucrose addition and removal, the time courses of Vms were the same as the time courses of the voltage signals produced by [TMA+]i, while the time courses of the voltage signals produced by [TBA+]o were much faster. These results suggest that the apparent streaming potentials are caused by changes of [NaCl] in the lateral intercellular spaces, whose time course reflects the changes in cell water volume (and osmolality) elicited by the alterations in apical solution osmolality. Changes in cell osmolality are slow relative to those of the apical solution osmolality, whereas lateral space osmolality follows cell osmolality rapidly, due to the large surface area of lateral membranes and the small volume of the spaces. Analysis of a simple mathematical model of the epithelium yields an apical membrane Lp in good agreement with previous measurements and suggests that elevations of the apical solution osmolality elicit rapid reductions in junctional ionic selectivity, also in good agreement with experimental determinations. Elevations in apical solution [NaCl] cause biphasic transepithelial voltage changes: a rapid negative Vms change of similar time course to that of a Na+/TBA+ bi-ionic potential and a slow positive Vms change of similar time course to that of the sucrose-induced apparent streaming potential. We conclude that the Vms changes elicited by addition of impermeant solute to the apical bathing solution are pseudo-streaming potentials, i.e., junctional diffusion potentials caused by salt concentration changes in the lateral intercellular spaces secondary to osmotic water flow from the cells to the apical bathing solution and from the lateral intercellular spaces to the cells. Our results do not support the notion of junctional solute-solvent coupling during transepithelial osmotic water flow.

scholarly journals Sodium and calcium currents in dispersed mammalian septal neurons.

1991 ◽  
Vol 97 (2) ◽  
pp. 303-320 ◽  
Author(s):  
A Castellano ◽  
J López-Barneo
Keyword(s):  
Time Constant ◽  
Time Course ◽  
Calcium Currents ◽  
Closing Time ◽  
Patch Clamp Technique ◽  
Average Value ◽  
Time To Peak ◽  
Time Courses ◽  
Fast Activation ◽  
Septal Neurons

Voltage-gated Na+ and Ca2+ conductances of freshly dissociated septal neurons were studied in the whole-cell configuration of the patch-clamp technique. All cells exhibited a large Na+ current with characteristic fast activation and inactivation time courses. Half-time to peak current at -20 mV was 0.44 +/- 0.18 ms and maximal activation of Na+ conductance occurred at 0 mV or more positive membrane potentials. The average value was 91 +/- 32 nS (approximately 11 mS cm-2). At all membrane voltages inactivation was well fitted by a single exponential that had a time constant of 0.44 +/- 0.09 ms at 0 mV. Recovery from inactivation was complete in approximately 900 ms at -80 mV but in only 50 ms at -120 mV. The decay of Na+ tail currents had a single time constant that at -80 mV was faster than 100 microseconds. Depolarization of septal neurons also elicited a Ca2+ current that peaked in approximately 6-8 ms. Maximal peak Ca2+ current was obtained at 20 mV, and with 10 mM external Ca2+ the amplitude was 0.35 +/- 0.22 nA. During a maintained depolarization this current partially inactivated in the course of 200-300 ms. The Ca2+ current was due to the activity of two types of conductances with different deactivation kinetics. At -80 mV the closing time constants of slow (SD) and fast (FD) deactivating channels were, respectively, 1.99 +/- 0.2 and 0.11 +/- 0.03 ms (25 degrees C). The two kinds of channels also differed in their activation voltage, inactivation time course, slope of the conductance-voltage curve, and resistance to intracellular dialysis. The proportion of SD and FD channels varied from cell to cell, which may explain the differential electrophysiological responses of intracellularly recorded septal neurons.

scholarly journals Mechanisms of autoantibody production in autoimmune MRL mice.

1980 ◽  
Vol 152 (5) ◽  
pp. 1302-1310 ◽  
Author(s):  
D S Pisetsky ◽  
G A McCarty ◽  
D V Peters
Keyword(s):  
Antibody Response ◽  
Time Course ◽  
Fundamental Difference ◽  
Autoantibody Production ◽  
Quantitative Expression ◽  
Autoantibody Response ◽  
Time Courses ◽  
Antibody Levels

The quantitative expression of anti-DNA and anti-Sm antibodies has been investigated in autoimmune MRL-lpr/lpr and MRL-+/+ mice. Anti-Sm antibodies were detected in sera from 21/23 lpr/lpr and 10/16 +/+ mice, with individual animals showing striking variation in the time-course and magnitude of this autoantibody response. The peak antibody levels of the responding animals of each substrain did not differ significantly. For anti-DNA antibody, a different pattern of responsiveness was observed. Individual animals of each substrain produced very similar responses in terms of the magnitude and time-course of serum anti-DNA antibody. The differences in the peak levels of the two substrains were highly significant, with lpr/lpr mice demonstrating a much greater anti-DNA antibody response than +/+ mice. In lpr/lpr mice tested for both autoantibody systems, serum anti-DNA and anti-Sm antibodies showed distinct time-courses. These studies indicate that anti-DNA and anti-Sm antibodies are expressed independently in MRL mice, with the expression of anti-DNA, but not anti-Sm antibody markedly influenced by the presence of the 1pr gene. A fundamental difference in the mechanisms involved in the generation of anti-DNA and anti-Sm antibodies is suggested by the quantitative pattern of the two responses.

scholarly journals The Rapid Extraction of Gist—Early Neural Correlates of High-level Visual Processing

2012 ◽  
Vol 24 (2) ◽  
pp. 521-529 ◽  
Author(s):  
Frank Oppermann ◽  
Uwe Hassler ◽  
Jörg D. Jescheniak ◽  
Thomas Gruber
Keyword(s):  
Visual Processing ◽  
Time Course ◽  
Occipital Cortex ◽  
Stimulus Onset ◽  
Gamma Band ◽  
Oscillatory Activity ◽  
Rapid Extraction ◽  
The Right ◽  
High Level ◽  
Individual Objects

The human cognitive system is highly efficient in extracting information from our visual environment. This efficiency is based on acquired knowledge that guides our attention toward relevant events and promotes the recognition of individual objects as they appear in visual scenes. The experience-based representation of such knowledge contains not only information about the individual objects but also about relations between them, such as the typical context in which individual objects co-occur. The present EEG study aimed at exploring the availability of such relational knowledge in the time course of visual scene processing, using oscillatory evoked gamma-band responses as a neural correlate for a currently activated cortical stimulus representation. Participants decided whether two simultaneously presented objects were conceptually coherent (e.g., mouse–cheese) or not (e.g., crown–mushroom). We obtained increased evoked gamma-band responses for coherent scenes compared with incoherent scenes beginning as early as 70 msec after stimulus onset within a distributed cortical network, including the right temporal, the right frontal, and the bilateral occipital cortex. This finding provides empirical evidence for the functional importance of evoked oscillatory activity in high-level vision beyond the visual cortex and, thus, gives new insights into the functional relevance of neuronal interactions. It also indicates the very early availability of experience-based knowledge that might be regarded as a fundamental mechanism for the rapid extraction of the gist of a scene.

Temporal Dynamics of Shape Analysis in Macaque Visual Area V2

2004 ◽  
Vol 92 (5) ◽  
pp. 3030-3042 ◽  
Author(s):  
Jay Hegdé ◽  
David C. Van Essen
Keyword(s):  
Cortical Neurons ◽  
Time Course ◽  
Temporal Dynamics ◽  
Visual Stimulation ◽  
Signal To Noise Ratio ◽  
Stimulus Onset ◽  
Visual Area ◽  
Response Modulation ◽  
Population Response ◽  
Area V2

The firing rate of visual cortical neurons typically changes substantially during a sustained visual stimulus. To assess whether, and to what extent, the information about shape conveyed by neurons in visual area V2 changes over the course of the response, we recorded the responses of V2 neurons in awake, fixating monkeys while presenting a diverse set of static shape stimuli within the classical receptive field. We analyzed the time course of various measures of responsiveness and stimulus-related response modulation at the level of individual cells and of the population. For a majority of V2 cells, the response modulation was maximal during the initial transient response (40–80 ms after stimulus onset). During the same period, the population response was relatively correlated, in that V2 cells tended to respond similarly to specific subsets of stimuli. Over the ensuing 80–100 ms, the signal-to-noise ratio of individual cells generally declined, but to a lesser degree than the evoked-response rate during the corresponding time bins, and the response profiles became decorrelated for many individual cells. Concomitantly, the population response became substantially decorrelated. Our results indicate that the information about stimulus shape evolves dynamically and relatively rapidly in V2 during static visual stimulation in ways that may contribute to form discrimination.

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