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Zhao S, Contadini-Wright C, Chait M. Cross-Modal Interactions Between Auditory Attention and Oculomotor Control. J Neurosci 2024; 44:e1286232024. [PMID: 38331581 PMCID: PMC10941240 DOI: 10.1523/jneurosci.1286-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 01/28/2024] [Accepted: 01/31/2024] [Indexed: 02/10/2024] Open
Abstract
Microsaccades are small, involuntary eye movements that occur during fixation. Their role is debated with recent hypotheses proposing a contribution to automatic scene sampling. Microsaccadic inhibition (MSI) refers to the abrupt suppression of microsaccades, typically evoked within 0.1 s after new stimulus onset. The functional significance and neural underpinnings of MSI are subjects of ongoing research. It has been suggested that MSI is a component of the brain's attentional re-orienting network which facilitates the allocation of attention to new environmental occurrences by reducing disruptions or shifts in gaze that could interfere with processing. The extent to which MSI is reflexive or influenced by top-down mechanisms remains debated. We developed a task that examines the impact of auditory top-down attention on MSI, allowing us to disentangle ocular dynamics from visual sensory processing. Participants (N = 24 and 27; both sexes) listened to two simultaneous streams of tones and were instructed to attend to one stream while detecting specific task "targets." We quantified MSI in response to occasional task-irrelevant events presented in both the attended and unattended streams (frequency steps in Experiment 1, omissions in Experiment 2). The results show that initial stages of MSI are not affected by auditory attention. However, later stages (∼0.25 s postevent onset), affecting the extent and duration of the inhibition, are enhanced for sounds in the attended stream compared to the unattended stream. These findings provide converging evidence for the reflexive nature of early MSI stages and robustly demonstrate the involvement of auditory attention in modulating the later stages.
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Affiliation(s)
- Sijia Zhao
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, United Kingdom
| | | | - Maria Chait
- Ear Institute, University College London, London WC1X 8EE, United Kingdom
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2
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Kadosh O, Inbal K, Snir H, Bonneh YS. Oculomotor inhibition markers of working memory load. Sci Rep 2024; 14:1872. [PMID: 38253785 PMCID: PMC10803752 DOI: 10.1038/s41598-024-52518-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 01/19/2024] [Indexed: 01/24/2024] Open
Abstract
Involuntary eye movements occur constantly even during fixation and were shown to convey information about cognitive processes. They are inhibited momentarily in response to external stimuli (oculomotor inhibition, OMI), with a time and magnitude that depend on stimulus saliency, attention, and expectations. It was recently shown that the working memory load for numbers modulates the microsaccade rate; however, the generality of the effect and its temporal properties remain unclear. Our goal was to investigate the relationship between OMI and the working memory load for simple colored shapes. Participants (N = 26) maintained their fixation while their eyes were tracked; they viewed briefly flashed colored shapes accompanied by small arrows indicating the shapes to be memorized (1/2/3). After a retention period, a probe shape appeared for matching. The microsaccade rate modulation and temporal properties were analyzed for the memory encoding, maintenance, and retrieval phases. Microsaccade inhibition was stronger when more shapes were memorized, and performance improved when microsaccades were suppressed during maintenance and retrieval. This occurred even though the physical stimuli were identical in number under all conditions. Thus, oculomotor inhibition may play a role in silencing the visual input while processing current stimuli and is generally related to processing time and load.
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Affiliation(s)
- Oren Kadosh
- School of Optometry and Vision Science, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Kfir Inbal
- School of Optometry and Vision Science, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Hadar Snir
- School of Optometry and Vision Science, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Yoram S Bonneh
- School of Optometry and Vision Science, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel.
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel.
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3
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Khademi F, Zhang T, Baumann MP, Buonocore A, Malevich T, Yu Y, Hafed ZM. Visual feature tuning properties of stimulus-driven saccadic inhibition in macaque monkeys. J Neurophysiol 2023; 130:1282-1302. [PMID: 37818591 DOI: 10.1152/jn.00289.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 10/03/2023] [Accepted: 10/03/2023] [Indexed: 10/12/2023] Open
Abstract
Saccadic inhibition refers to a short-latency transient cessation of saccade generation after visual sensory transients. This oculomotor phenomenon occurs with a latency that is consistent with a rapid influence of sensory responses, such as stimulus-induced visual bursts, on oculomotor control circuitry. However, the neural mechanisms underlying saccadic inhibition are not well understood. Here, we exploited the fact that macaque monkeys experience robust saccadic inhibition to test the hypothesis that inhibition time and strength exhibit systematic visual feature tuning properties to a multitude of visual feature dimensions commonly used in vision science. We measured saccades in three monkeys actively controlling their gaze on a target, and we presented visual onset events at random times. Across seven experiments, the visual onsets tested size, spatial frequency, contrast, orientation, motion direction, and motion speed dependencies of saccadic inhibition. We also investigated how inhibition might depend on the behavioral relevance of the appearing stimuli. We found that saccadic inhibition starts earlier, and is stronger, for large stimuli of low spatial frequencies and high contrasts. Moreover, saccadic inhibition timing depends on motion direction and orientation, with earlier inhibition systematically occurring for horizontally drifting vertical gratings. On the other hand, saccadic inhibition is stronger for faster motions and when the appearing stimuli are subsequently foveated. Besides documenting a range of feature tuning dimensions of saccadic inhibition to the properties of exogenous visual stimuli, our results establish macaque monkeys as an ideal model system for unraveling the neural mechanisms underlying a ubiquitous oculomotor phenomenon in visual neuroscience.NEW & NOTEWORTHY Visual onsets dramatically reduce saccade generation likelihood with very short latencies. Such latencies suggest that stimulus-induced visual responses, normally jump-starting perceptual and scene analysis processes, can also directly impact the decision of whether to generate saccades or not, causing saccadic inhibition. Consistent with this, we found that changing the appearance of the visual onsets systematically alters the properties of saccadic inhibition. These results constrain neurally inspired models of coordination between saccade generation and exogenous sensory stimulation.
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Affiliation(s)
- Fatemeh Khademi
- Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen, Germany
| | - Tong Zhang
- Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen, Germany
| | - Matthias P Baumann
- Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen, Germany
| | - Antimo Buonocore
- Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen, Germany
- Department of Educational, Psychological and Communication Sciences, Suor Orsola Benincasa University, Naples, Italy
| | - Tatiana Malevich
- Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen, Germany
| | - Yue Yu
- Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen, Germany
| | - Ziad M Hafed
- Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen, Germany
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4
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Barquero C, Chen JT, Munoz DP, Wang CA. Human microsaccade cueing modulation in visual- and memory-delay saccade tasks after theta burst transcranial magnetic stimulation over the frontal eye field. Neuropsychologia 2023; 187:108626. [PMID: 37336260 DOI: 10.1016/j.neuropsychologia.2023.108626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 06/15/2023] [Accepted: 06/16/2023] [Indexed: 06/21/2023]
Abstract
Microsaccades that occur during periods of fixation are modulated by various cognitive processes and have an impact on visual processing. A network of brain areas is involved in microsaccade generation, including the superior colliculus and frontal eye field (FEF) which are involved in modulating microsaccade rate and direction after the appearance of a visual cue (referred to as microsaccade cueing modulation). Although the neural mechanisms underlying microsaccade cueing modulations have been demonstrated in monkeys, limited research has investigated a causal role of these areas in humans. By applying continuous theta-burst transcranial magnetic stimulation (cTBS) over the right FEF and vertex, we investigated the role of human FEF in modulating microsaccade responses after the appearance of a visual target in a visual- and memory-delay saccade task. After target appearance, microsaccade rate was initially suppressed but then increased in both cTBS conditions. More importantly, in the visual-delay task, microsaccades after target appearance were directed to the ipsilateral side more often with FEF, compared to vertex stimulation. Moreover, microsaccades were directed towards the target location, then to the opposite location of the target in both tasks, with larger effects in the visual-, compared to, memory-delay task. This microsaccade direction modulation was delayed after FEF stimulation in the memory-delay task. Overall, some microsaccade cueing modulations were moderately disrupted after FEF cTBS, suggesting a causal role for involvement of the human FEF in microsaccade generation after presentation of salient stimuli.
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Affiliation(s)
- Cesar Barquero
- Eye-Tracking Laboratory, Brain and Consciousness Research Center, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan; Institute of Cognitive Neuroscience, College of Health Science and Technology, National Central University, Taoyuan City, Taiwan; Department of Physical Activity and Sport Science, Universidad Peruana de Ciencias Aplicadas, Lima, Peru
| | - Jui-Tai Chen
- Department of Anesthesiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei City, Taiwan; Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
| | - Douglas P Munoz
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Chin-An Wang
- Eye-Tracking Laboratory, Brain and Consciousness Research Center, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan; Institute of Cognitive Neuroscience, College of Health Science and Technology, National Central University, Taoyuan City, Taiwan; Department of Anesthesiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei City, Taiwan; Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.
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5
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Raffi M, Trofè A, Meoni A, Gallelli L, Piras A. Optic Flow Speed and Retinal Stimulation Influence Microsaccades. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19116765. [PMID: 35682346 PMCID: PMC9180672 DOI: 10.3390/ijerph19116765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 05/28/2022] [Accepted: 05/29/2022] [Indexed: 02/04/2023]
Abstract
Microsaccades are linked with extraretinal mechanisms that significantly alter spatial perception before the onset of eye movements. We sought to investigate whether microsaccadic activity is modulated by the speed of radial optic flow stimuli. Experiments were performed in the dark on 19 subjects who stood in front of a screen covering 135 × 107° of the visual field. Subjects were instructed to fixate on a central fixation point while optic flow stimuli were presented in full field, in the foveal, and in the peripheral visual field at different dot speeds (8, 11, 14, 17, and 20°/s). Fixation in the dark was used as a control stimulus. For almost all tested speeds, the stimulation of the peripheral retina evoked the highest microsaccade rate. We also found combined effects of optic flow speed and the stimulated retinal region (foveal, peripheral, and full field) for microsaccade latency. These results show that optic flow speed modulates microsaccadic activity when presented in specific retinal portions, suggesting that eye movement generation is strictly dependent on the stimulated retinal regions.
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Affiliation(s)
- Milena Raffi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (A.M.); (A.P.)
- Correspondence:
| | - Aurelio Trofè
- Department of Quality of Life, University of Bologna, 47921 Rimini, Italy;
| | - Andrea Meoni
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (A.M.); (A.P.)
| | - Luca Gallelli
- Department of Health Science, School of Medicine, University of Catanzaro, 88100 Catanzaro, Italy;
- Clinical Pharmacology and Pharmacovigilance Unit, Mater Domini Hospital Catanzaro, 88100 Catanzaro, Italy
| | - Alessandro Piras
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (A.M.); (A.P.)
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6
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Abstract
While aiming and shooting, we make tiny eye movements called microsaccades that shift gaze between task-relevant objects within a small region of the visual field. However, in the brief period before pressing the trigger, microsaccades are suppressed. This might be due to the lack of a requirement to shift gaze as the retinal images of the two objects begin to overlap on the fovea. Alternatively, we might actively suppress microsaccades to prevent any disturbances in visual perception caused by microsaccades around the time of their occurrence and their subsequent effect on shooting performance. In this study we looked at microsaccade rates while participants performed a simulated shooting task under two conditions: a normal condition in which they moved their eyes freely, and an eccentric condition in which they maintained gaze on a fixed target while performing the shooting task at 5° eccentricity. As expected, microsaccade rate dropped near the end of the task in the normal viewing condition. However, we also found the same decrease for the eccentric condition in which microsaccades did not shift gaze between the task objects. Microsaccades are also produced in response to shifts in covert attention. To test whether disengagement of covert attention from the eccentric shooting location caused the drop in microsaccade rate, we monitored the location of participants' spatial attention by using a Rapid Serial Visual Presentation (RSVP) task simultaneously at a location opposite to the shooting task. Target letter detection at the RSVP location did not improve during the drop in microsaccade rate, suggesting that covert attention was maintained at the shooting task location. We conclude that in addition to their usual gaze-shifting function, microsaccades during fine-acuity tasks might be modulated by cognitive processes other than spatial attention.
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Affiliation(s)
- Rakesh Nanjappa
- Graduate Center for Vision Research, Department of Biological and Visual Sciences, SUNY College of Optometry, New York, NY, USA.,Present address: Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA.,
| | - Robert M McPeek
- Graduate Center for Vision Research, Department of Biological and Visual Sciences, SUNY College of Optometry, New York, NY, USA.,
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7
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Schneider A, Sonderegger A, Krueger E, Meteier Q, Luethold P, Chavaillaz A. The interplay between task difficulty and microsaccade rate: Evidence for the critical role of visual load. J Eye Mov Res 2021; 13:10.16910/jemr.13.5.6. [PMID: 34122745 PMCID: PMC8188521 DOI: 10.16910/jemr.13.5.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In previous research, microsaccades have been suggested as psychophysiological indicators of task load. So far, it is still under debate how different types of task demands are influencing microsaccade rate. This piece of research examines the relation between visual load, mental load and microsaccade rate. Fourteen participants carried out a continuous performance task (n-back), in which visual (letters vs. abstract figures) and mental task load (1-back to 4-back) were manipulated as within-subjects variables. Eye tracking data, performance data as well as subjective workload were recorded. Data analysis revealed an increased level of microsaccade rate for stimuli of high visual demand (i.e. abstract figures), while mental demand (n-back-level) did not modulate microsaccade rate. In conclusion, the present results suggest that microsaccade rate reflects visual load of a task rather than its mental load.
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8
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Kadem M, Herrmann B, Rodd JM, Johnsrude IS. Pupil Dilation Is Sensitive to Semantic Ambiguity and Acoustic Degradation. Trends Hear 2021; 24:2331216520964068. [PMID: 33124518 PMCID: PMC7607724 DOI: 10.1177/2331216520964068] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Speech comprehension is challenged by background noise, acoustic interference, and linguistic factors, such as the presence of words with more than one meaning (homonyms and homophones). Previous work suggests that homophony in spoken language increases cognitive demand. Here, we measured pupil dilation—a physiological index of cognitive demand—while listeners heard high-ambiguity sentences, containing words with more than one meaning, or well-matched low-ambiguity sentences without ambiguous words. This semantic-ambiguity manipulation was crossed with an acoustic manipulation in two experiments. In Experiment 1, sentences were masked with 30-talker babble at 0 and +6 dB signal-to-noise ratio (SNR), and in Experiment 2, sentences were heard with or without a pink noise masker at –2 dB SNR. Speech comprehension was measured by asking listeners to judge the semantic relatedness of a visual probe word to the previous sentence. In both experiments, comprehension was lower for high- than for low-ambiguity sentences when SNRs were low. Pupils dilated more when sentences included ambiguous words, even when no noise was added (Experiment 2). Pupil also dilated more when SNRs were low. The effect of masking was larger than the effect of ambiguity for performance and pupil responses. This work demonstrates that the presence of homophones, a condition that is ubiquitous in natural language, increases cognitive demand and reduces intelligibility of speech heard with a noisy background.
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Affiliation(s)
- Mason Kadem
- Department of Psychology, The University of Western Ontario, London, Ontario, Canada.,School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
| | - Björn Herrmann
- Department of Psychology, The University of Western Ontario, London, Ontario, Canada.,Rotman Research Institute, Baycrest, Toronto, Ontario, Canada.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada
| | - Jennifer M Rodd
- Department of Experimental Psychology, University College London, London, United Kingdom
| | - Ingrid S Johnsrude
- Department of Psychology, The University of Western Ontario, London, Ontario, Canada.,School of Communication and Speech Disorders, The University of Western Ontario, London, Ontario, Canada
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9
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Raffi M, Trofè A, Perazzolo M, Meoni A, Piras A. Sensory Input Modulates Microsaccades during Heading Perception. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:2865. [PMID: 33799672 PMCID: PMC8000400 DOI: 10.3390/ijerph18062865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/04/2021] [Accepted: 03/07/2021] [Indexed: 11/21/2022]
Abstract
Microsaccades are small eye movements produced during attempted fixation. During locomotion, the eyes scan the environment; the gaze is not always directed to the focus of expansion of the optic flow field. We sought to investigate whether the microsaccadic activity was modulated by eye position during the view of radial optic flow stimuli, and if the presence or lack of a proprioceptive input signal may influence the microsaccade characteristics during self-motion perception. We recorded the oculomotor activity when subjects were either standing or sitting in front of a screen during the view of optic flow stimuli that simulated specific heading directions with different gaze positions. We recorded five trials of each stimulus. Results showed that microsaccade duration, peak velocity, and rate were significantly modulated by optic flow stimuli and trial sequence. We found that the microsaccade rate increased in each condition from trial 1 to trial 5. Microsaccade peak velocity and duration were significantly different across trials. The analysis of the microsaccade directions showed that the different combinations of optic flow and eye position evoked non-uniform directions of microsaccades in standing condition with mean vectors in the upper-left quadrant of the visual field, uncorrelated with optic flow directions and eye positions. In sitting conditions, all stimuli evoked uniform directions of microsaccades. Present results indicate that the proprioceptive signals when the subjects stand up creates a different input that could alter the eye-movement characteristics during heading perceptions.
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Affiliation(s)
- Milena Raffi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (M.P.); (A.M.); (A.P.)
| | - Aurelio Trofè
- Department of Quality of Life, University of Bologna, 47921 Rimini, Italy;
| | - Monica Perazzolo
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (M.P.); (A.M.); (A.P.)
| | - Andrea Meoni
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (M.P.); (A.M.); (A.P.)
| | - Alessandro Piras
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (M.P.); (A.M.); (A.P.)
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10
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Chen JT, Yep R, Hsu YF, Cherng YG, Wang CA. Investigating Arousal, Saccade Preparation, and Global Luminance Effects on Microsaccade Behavior. Front Hum Neurosci 2021; 15:602835. [PMID: 33746722 PMCID: PMC7973374 DOI: 10.3389/fnhum.2021.602835] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/09/2021] [Indexed: 11/28/2022] Open
Abstract
Microsaccades, small saccadic eye movements occurring during fixation, have been suggested to be modulated by various sensory, cognitive, and affective processes relating to arousal. Although the modulation of fatigue-related arousal on microsaccade behavior has previously been characterized, the influence of other aspects of arousal, such as emotional arousal, is less understood. Moreover, microsaccades are modulated by cognitive processes (e.g., voluntary saccade preparation) that could also be linked to arousal. To investigate the influence of emotional arousal, saccade preparation, and global luminance levels on microsaccade behavior, emotional auditory stimuli were presented prior to the onset of a fixation cue whose color indicated to look either at the peripheral stimulus (pro-saccade) or in the opposite direction of the stimulus (anti-saccade). Microsaccade behavior was found to be significantly modulated by saccade preparation and global luminance level, but not emotional arousal. In the pro- and anti-saccade task, microsaccade rate was lower during anti-saccade preparation as compared to pro-saccade preparation, though microsaccade dynamics were comparable during both trial types. Our results reveal a differential role of arousal linked to emotion, fatigue, saccade preparation, and global luminance level on microsaccade behavior.
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Affiliation(s)
- Jui-Tai Chen
- Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, Taipei City, Taiwan
- Department of Anesthesiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei City, Taiwan
| | - Rachel Yep
- Centre for Neuroscience Studies, Queen’s University, Kingston, ON, Canada
| | - Yu-Fan Hsu
- Research Center of Brain and Consciousness, Shuang Ho Hospital, Taipei Medical University, Taipei City, Taiwan
- Graduate Institute of Mind, Brain, and Consciousness, Taipei Medical University, Taipei City, Taiwan
| | - Yih-Giun Cherng
- Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, Taipei City, Taiwan
- Department of Anesthesiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei City, Taiwan
| | - Chin-An Wang
- Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, Taipei City, Taiwan
- Research Center of Brain and Consciousness, Shuang Ho Hospital, Taipei Medical University, Taipei City, Taiwan
- Graduate Institute of Mind, Brain, and Consciousness, Taipei Medical University, Taipei City, Taiwan
- Institute of Cognitive Neuroscience, College of Health Science and Technology, National Central University, Taoyuan City, Taiwan
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11
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Roberts MJ, Lange G, Van Der Veen T, Lowet E, De Weerd P. The Attentional Blink is Related to the Microsaccade Rate Signature. Cereb Cortex 2019; 29:5190-5203. [PMID: 30941400 DOI: 10.1093/cercor/bhz058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/26/2019] [Accepted: 03/02/2019] [Indexed: 11/15/2022] Open
Abstract
The reduced detectability of a target T2 following discrimination of a preceding target T1 in the attentional blink (AB) paradigm is classically interpreted as a consequence of reduced attention to T2 due to attentional allocation to T1. Here, we investigated whether AB was related to changes in microsaccade rate (MSR). We found a pronounced MSR signature following T1 onset, characterized by MSR suppression from 200 to 328 ms and enhancement from 380 to 568 ms. Across participants, the magnitude of the MSR suppression correlated with the AB effect such that low T2 detectability corresponded to reduced MSR. However, in the same task, T1 error trials coincided with the presence of microsaccades. We discuss this apparent paradox in terms of known neurophysiological correlates of MS whereby cortical excitability is suppressed both during the microsaccade and MSR suppression, in accordance to poor T1 performance with microsaccade occurrence and poor T2 performance with microsaccade absence. Our data suggest a novel low-level mechanism contributing to AB characterized by reduced MSR, thought to cause suppressed visual cortex excitability. This opens the question of whether attention mediates T2 performance suppression independently from MSR, and if not, how attention interacts with MSR to produce the T2 performance suppression.
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Affiliation(s)
- Mark J Roberts
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Gesa Lange
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Tracey Van Der Veen
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Eric Lowet
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Biology, Boston University, Boston, MA, USA
| | - Peter De Weerd
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Maastricht Centre for Systems Biology (MaCSBio), Faculty of Science and Engineering, Maastricht, The Netherlands
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12
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Hampsey E, Overton PG, Stafford T. Microsaccade rate as a measure of drug response. J Eye Mov Res 2019; 12:10.16910/jemr.12.6.12. [PMID: 33828750 PMCID: PMC7962677 DOI: 10.16910/jemr.12.6.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
In 22 human subjects we measured microsaccade count across 60 brief fixation trials both pre- and post- administration of 300mg of caffeine. There was a statistically significant reduction in average microsaccade count post-caffeine administration, with a moderate effect size (Cohen's d of 0.42). Microsaccade count was stable within individuals across time points (Pearson's r of 0.89). Sensitivity analysis suggests that the pre/post caffeine effect size is robust to choice of parameters used to identify microsaccades. Bootstrap resampling suggests that both the pre/post-caffeine difference and the across-time stability within individuals could be reliably assessed with far fewer trials. The results support the use of microsaccade count as both a trait measure of individual differences and a state measure of caffeine response. We discuss the results in the context of the theory that the superior colliculus is central to the generation of microsaccades and hence that microsaccade rate may be a useful assay for at least some drug-induced changes at the level of the colliculus: a potentially useful tool in the development of therapies for disorders that may involve collicular dysfunction such as ADHD.
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Affiliation(s)
| | | | - Tom Stafford
- Department of Psychology, University of Sheffield, UK
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Krueger E, Schneider A, Sawyer BD, Chavaillaz A, Sonderegger A, Groner R, Hancock PA. Microsaccades Distinguish Looking From Seeing. J Eye Mov Res 2019; 12. [PMID: 33828752 PMCID: PMC7962679 DOI: 10.16910/jemr.12.6.2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Understanding our visual world requires both looking and seeing. Dissociation of these processes can result in the phenomenon of inattentional blindness or 'looking without seeing'. Concomitant errors in applied settings can be serious, and even deadly. Current visual data analysis cannot differentiate between just 'looking' and actual processing of visual information, i.e., 'seeing'. Differentiation may be possible through the examination of microsaccades; the involuntary, smallmagnitude saccadic eye movements that occur during processed visual fixation. Recent work has suggested that microsaccades are post-attentional biosignals, potentially modulated by task. Specifically, microsaccade rates decrease with increased mental task demand, and increase with growing visual task difficulty. Such findings imply that there are fundamental differences in microsaccadic activity between visual and nonvisual tasks. To evaluate this proposition, we used a high-speed eye tracker to record participants in looking for differences between two images or, doing mental arithmetic, or both tasks in combination. Results showed that microsaccade rate was significantly increased in conditions that require high visual attention, and decreased in conditions that require less visual attention. The results support microsaccadic rate reflecting visual attention, and level of visual information processing. A measure that reflects to what extent and how an operator is processing visual information represents a critical step for the application of sophisticated visual assessment to real world tasks.
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Dalmaso M, Castelli L, Galfano G. Microsaccadic rate and pupil size dynamics in pro-/anti-saccade preparation: the impact of intermixed vs. blocked trial administration. PSYCHOLOGICAL RESEARCH 2019; 84:1320-1332. [PMID: 30603866 DOI: 10.1007/s00426-018-01141-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 12/21/2018] [Indexed: 01/02/2023]
Abstract
Prolonged fixation can lead to the generation of tiny and fast eye movements called microsaccades, whose dynamics can be associated with higher cognitive mechanisms. Saccade preparation is also reflected in microsaccadic activity, but the few studies on this topic provided mixed results. For instance, fewer microsaccades have been observed when participants were asked to prepare for an anti-saccade (i.e., a saccade in the opposite direction to the target) as compared to a pro-saccade (i.e., a saccade executed towards a target), but null results have also been reported. In the attempt to shed new light on this topic, two experiments were carried out in which the context of presentation of pro- and anti-saccade trials was manipulated. Pupil size was also recorded, as a further index of cognitive load. In Experiment 1, participants were asked to prepare and perform pro- and anti-saccades in response to a peripheral target, according to a central instruction cue provided at the beginning of each trial (intermixed condition). In Experiment 2, the same task was employed, but pro- and anti-saccade trials were delivered in two distinct blocks (blocked condition). In both experiments, greater saccadic latencies and lower accuracy emerged for anti- than for pro-saccades. However, in the intermixed condition, a lower microsaccadic rate and a greater pupil size emerged when participants prepared for anti- rather than pro-saccades, whereas these differences disappeared in the blocked condition. These results suggest that contextual factors may play a key role in shaping oculomotor dynamics linked to saccade preparation.
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Affiliation(s)
- Mario Dalmaso
- Department of Developmental and Social Psychology, University of Padova, Via Venezia 8, 35131, Padua, Italy.
| | - Luigi Castelli
- Department of Developmental and Social Psychology, University of Padova, Via Venezia 8, 35131, Padua, Italy
| | - Giovanni Galfano
- Department of Developmental and Social Psychology, University of Padova, Via Venezia 8, 35131, Padua, Italy
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