scholarly journals Audiovisual integration in the Mauthner cell enhances escape probability and reduces response latency

2021 ◽  
Author(s):  
Nicolas Martorell ◽  
Violeta Medan

Fast and accurate threat detection is critically important for animal survival. Reducing perceptual ambiguity by integrating multiple sources of sensory information can enhance threat detection and reduce response latency. However, studies showing a direct link between behavioral correlates of multisensory integration and its underlying neural basis are rare. In fish, an explosive escape behavior known as C-start is driven by an identified neural circuit centered on the Mauthner cell. The Mauthner cell can trigger C-starts in response to visual and auditory stimuli allowing to investigate how multisensory integration in a single neuron affects behavioral outcome after threat detection. Here we demonstrate that in goldfish visual looms and brief auditory stimuli can be integrated to increase C-start probability and that this enhancement is inversely correlated to the saliency of the cues with weaker auditory cues producing a proportionally stronger multisensory effect. We also show that multisensory stimuli reduce response latency locked to the presentation of the auditory cue. Finally, we make a direct link between behavioral data and its underlying neural mechanism by reproducing empirical data with an integrate-and-fire computational model of the Mauthner cell.

Author(s):  
Jingjing Yang ◽  
Qi Li ◽  
Yulin Gao ◽  
Jinglong Wu

In everyday life, our brains integrate various kinds of information from different modalities to perceive our complex environment. Spatial and temporal proximity of multisensory stimuli is required for multisensory integration. Many researches have shown that temporal asynchrony of visual-auditory stimuli can influence multisensory integration. However, the neural mechanisms of asynchrony inputs were not well understood. Some researchers believe that humans have a relatively broad time window, in which stimuli from different modalities and asynchronous inputs tends to be integrated into a single unified percept. Others believe that the human brain can actively coordinate the auditory and visual input so that we do not notice the asynchronous inputs of multisensory stimuli. This review focuses on the question of how the temporal factor affects the processing of audiovisual information.


BJPsych Open ◽  
2018 ◽  
Vol 4 (5) ◽  
pp. 317-323 ◽  
Author(s):  
Asako Mori ◽  
Yasumasa Okamoto ◽  
Go Okada ◽  
Koki Takagaki ◽  
Masahiro Takamura ◽  
...  

BackgroundBehavioural activation is an efficient treatment for depression and can improve intrinsic motivation. Previous studies have revealed that the frontostriatal circuit is involved in intrinsic motivation; however, there are no data on how behavioural activation affects the frontostriatal circuit.AimsWe aimed to investigate behavioural activation-related changes in the frontostriatal circuit.MethodFifty-nine individuals with subthreshold depression were randomly assigned to either the intervention or non-intervention group. The intervention group received five weekly behavioural activation sessions. The participants underwent functional magnetic resonance imaging scanning on two separate occasions while performing a stopwatch task based on intrinsic motivation. We investigated changes in neural activity and functional connectivity after behavioural activation.ResultsAfter behavioural activation, the intervention group had increased activation and connectivity in the frontostriatal region compared with the non-intervention group. The increased activation in the right middle frontal gyrus was correlated with an improvement of subjective sensitivity to environmental rewards.ConclusionsBehavioural activation-related changes to the frontostriatal circuit advance our understanding of psychotherapy-induced improvements in the neural basis of intrinsic motivation.Declaration of interestNone.


2005 ◽  
Vol 94 (4) ◽  
pp. 2644-2652 ◽  
Author(s):  
Makoto Araki ◽  
Toshiki Nagayama ◽  
Jordanna Sprayberry

The lateral giant (LG)-mediated escape behavior of the crayfish habituates readily on repetitive sensory stimulation. Recent studies suggested that the biogenic amines serotonin and octopamine modulate the time course of recovery and/or re-depression of the LG response after habituation. However, little is known of how serotonin and octopamine effect LG habituation and what second-messenger cascades they may activate. To investigate the effect of biogenic amines on LG habituation, serotonin and octopamine were superfused before presenting repetitive sensory stimulation. Serotonin and octopamine increased the number of stimuli needed to habituate the LG response. Their effects were mimicked by mixed application of a cAMP analogue [8-(4-chlorophenylthio)-cAMP (CPT-cAMP)] and a phosphodiesterase inhibitor [3-isobutyl-1-methylxanthine (IBMX)] but not by a cGMP analogue (8-bromoguanosine 3′,5′-cyclic monophosphate). Perfusion of the adenylate cyclase inhibitor (SQ22536) abolished the effect of serotonin but not that of octopamine. To investigate the site of action of each biogenic amines in the neural circuit meditating LG escape, the effect of drugs on directly and indirectly elicited postsynaptic potentials in LG was investigated. Serotonin, octopamine, and a mixture of CPT-cAMP and IBMX increased both the direct and indirect synaptic inputs. Simultaneous application of SQ22536 abolished the effect of serotonin on both inputs but did not block the effect of octopamine. Direct injection of the cAMP analogue (Sp-isomer of adenosine-3′,5′-cyclic monophosphorothioate) into LG increased both the direct and indirect inputs to LG. These results indicate that serotonin mediates an increase in cAMP levels in LG, but octopamine acts independently of cAMP and cGMP.


eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
William Thomas Keenan ◽  
Alan C Rupp ◽  
Rachel A Ross ◽  
Preethi Somasundaram ◽  
Suja Hiriyanna ◽  
...  

Rapid and stable control of pupil size in response to light is critical for vision, but the neural coding mechanisms remain unclear. Here, we investigated the neural basis of pupil control by monitoring pupil size across time while manipulating each photoreceptor input or neurotransmitter output of intrinsically photosensitive retinal ganglion cells (ipRGCs), a critical relay in the control of pupil size. We show that transient and sustained pupil responses are mediated by distinct photoreceptors and neurotransmitters. Transient responses utilize input from rod photoreceptors and output by the classical neurotransmitter glutamate, but adapt within minutes. In contrast, sustained responses are dominated by non-conventional signaling mechanisms: melanopsin phototransduction in ipRGCs and output by the neuropeptide PACAP, which provide stable pupil maintenance across the day. These results highlight a temporal switch in the coding mechanisms of a neural circuit to support proper behavioral dynamics.


2021 ◽  
Author(s):  
Nodoka Sato ◽  
Hisashi Shidara ◽  
Hiroto Ogawa

ABSTRACTAnimals detect approaching predators via sensory inputs through various modalities and immediately show an appropriate behavioral response to survive. Escape behavior is essential to avoid the predator’s attack and is more frequently observed than other defensive behaviors. In some species, multiple escape responses are exhibited with different movements. It has been reported that the approaching speed of a predator is important in choosing which escape action to take among the multiple responses. However, it is unknown whether other aspects of sensory stimuli, that indicate the predator’s approach, affect the selection of escape responses. We focused on two distinct escape responses (running and jumping) to a stimulus (short airflow) in crickets and examined the effects of multiple stimulus aspects (including the angle, velocity, and duration) on the choice between these escape responses. We found that the faster and longer the airflow, the more frequently the crickets jumped, meaning that they could choose their escape response depending on both velocity and duration of the stimulus. This result suggests that the neural basis for choosing escape responses includes the integration process of multiple stimulus parameters. It was also found that the moving speed and distance changed depending on the stimulus velocity and duration during running but not during jumping, suggesting higher adaptability of the running escape. In contrast, the movement direction was accurately controlled regardless of the stimulus parameters in both responses. The escape direction depended only on stimulus orientation, but not on velocity and duration.Summary statementWhen air currents triggering escape are faster and longer, crickets more frequently jump than run. Running speed and distance depend on stimulus velocity and duration, but direction control is independent.


2007 ◽  
Vol 97 (1) ◽  
pp. 921-926 ◽  
Author(s):  
Mark T. Wallace ◽  
Barry E. Stein

Multisensory integration refers to the process by which the brain synthesizes information from different senses to enhance sensitivity to external events. In the present experiments, animals were reared in an altered sensory environment in which visual and auditory stimuli were temporally coupled but originated from different locations. Neurons in the superior colliculus developed a seemingly anomalous form of multisensory integration in which spatially disparate visual-auditory stimuli were integrated in the same way that neurons in normally reared animals integrated visual-auditory stimuli from the same location. The data suggest that the principles governing multisensory integration are highly plastic and that there is no a priori spatial relationship between stimuli from different senses that is required for their integration. Rather, these principles appear to be established early in life based on the specific features of an animal's environment to best adapt it to deal with that environment later in life.


2020 ◽  
Vol 43 (1) ◽  
pp. 417-439 ◽  
Author(s):  
Tiago Branco ◽  
Peter Redgrave

Escape is one of the most studied animal behaviors, and there is a rich normative theory that links threat properties to evasive actions and their timing. The behavioral principles of escape are evolutionarily conserved and rely on elementary computational steps such as classifying sensory stimuli and executing appropriate movements. These are common building blocks of general adaptive behaviors. Here we consider the computational challenges required for escape behaviors to be implemented, discuss possible algorithmic solutions, and review some of the underlying neural circuits and mechanisms. We outline shared neural principles that can be implemented by evolutionarily ancient neural systems to generate escape behavior, to which cortical encephalization has been added to allow for increased sophistication and flexibility in responding to threat.


i-Perception ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 204166952096661
Author(s):  
Yasuhiro Takeshima

Audiovisual integration relies on temporal synchrony between visual and auditory stimuli. The brain rapidly adapts to audiovisual asynchronous events by shifting the timing of subjective synchrony in the direction of the leading modality of the most recent event, a process called rapid temporal recalibration. This phenomenon is the flexible function of audiovisual synchrony perception. Previous studies found that neural processing speed based on spatial frequency (SF) affects the timing of subjective synchrony. This study examined the effects of SF on the rapid temporal recalibration process by discriminating whether the presentation of the visual and auditory stimuli was simultaneous. I compared the magnitudes of the recalibration effect between low and high SF visual stimuli using two techniques. First, I randomly presented each SF accompanied by a tone during one session, then in a second experiment, only a single SF was paired with the tone throughout the one session. The results indicated that rapid recalibration occurred regardless of difference in presented SF between preceding and test trials. The recalibration magnitude did not significantly differ between the SF conditions. These findings confirm that intersensory temporal process is important to produce rapid recalibration and suggest that rapid recalibration can be induced by the simultaneity judgment criterion changes attributed to the low-level temporal information of audiovisual events.


1992 ◽  
Vol 67 (6) ◽  
pp. 1574-1586 ◽  
Author(s):  
J. R. Fetcho

1. The Mauthner cell in fish and amphibians initiates an escape behavior that has served as a model system for studies of the reticulospinal control of movement. This behavior consists of a very rapid bend of the body and tail that is thought to arise from the monosynaptic excitation of large primary motoneurons by the Mauthner cell. Recent work suggests that the excitation of primary motoneurons might be more complex than a solely monosynaptic connection. To examine this possibility, I used intracellular recording and staining to study the excitation of primary motoneurons by the M cell. 2. Simultaneous intracellular recordings from the M axon and ipsilateral primary motoneurons show that firing the M cell leads to complex postsynaptic potentials (PSPs) in the motoneurons. These PSPs usually have three components: an early, small, slow depolarization (component 1), a later, large, fast depolarization (component 2), and an even later, large, long-lasting depolarization (component 3). The first component has a latency of 0.52 +/- 0.15 (SD) ms, (n = 27) and most probably is a monosynaptic input from the M cell. This study focused on the two subsequent, less-understood parts of the PSP. Motoneurons typically fire off the second part of the PSP. This is usually (27 of 33 cells) the largest component, and it has a mean amplitude of 6.24 +/- 3.33 (SD) mV (n = 33) and a half-decay time of 0.44 +/- 0.18 (SD) ms (n = 27). The mean amplitude of the third component is 3.20 +/- 1.7 (SD) mV (n = 35), and its half-decay is 6.73 +/- 2.66 (SD) ms (n = 35). The latency of the second component averages 0.66 +/- 0.21 (SD) ms (n = 32), indicating that there are few synapses in the pathway mediating it. 3. One candidate pathway for the second component of the PSP involves a class of descending interneurons (DIs) that are monosynaptically, chemically excited by the M cell and appear in light microscopy to contact motoneurons. Simultaneous intracellular recordings from the M axon, a DI, and a primary motoneuron show that the interneurons are electrotonically coupled to motoneurons and produce the fast, second component of the PSP. Direct excitation of an interneuron leads to a very short-latency (less than 0.2 ms), fast PSP in a motoneuron similar to the second component of the PSP produced by the M axon. The short latency and fatigue resistance of this connection indicate it is electrotonic, and this is supported by evidence for DC coupling between the two cells.(ABSTRACT TRUNCATED AT 400 WORDS)


Perception ◽  
2016 ◽  
Vol 46 (1) ◽  
pp. 6-17 ◽  
Author(s):  
N. Van der Stoep ◽  
S. Van der Stigchel ◽  
T. C. W. Nijboer ◽  
C. Spence

Multisensory integration (MSI) and exogenous spatial attention can both speedup responses to perceptual events. Recently, it has been shown that audiovisual integration at exogenously attended locations is reduced relative to unattended locations. This effect was observed at short cue-target intervals (200–250 ms). At longer intervals, however, the initial benefits of exogenous shifts of spatial attention at the cued location are often replaced by response time (RT) costs (also known as Inhibition of Return, IOR). Given these opposing cueing effects at shorter versus longer intervals, we decided to investigate whether MSI would also be affected by IOR. Uninformative exogenous visual spatial cues were presented between 350 and 450 ms prior to the onset of auditory, visual, and audiovisual targets. As expected, IOR was observed for visual targets (invalid cue RT < valid cue RT). For auditory and audiovisual targets, neither IOR nor any spatial cueing effects were observed. The amount of relative multisensory response enhancement and race model inequality violation was larger for uncued as compared with cued locations indicating that IOR reduces MSI. The results are discussed in the context of changes in unisensory signal strength at cued as compared with uncued locations.


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