Comparison of Pupil Dilation Responses to Unexpected Sounds in Monkeys and Humans

Pupil dilation in response to unexpected stimuli has been well documented in human as well as in non-human primates; however, this phenomenon has not been systematically compared between the species. This analogy is also crucial for the role of non-human primates as an animal model to investigate neural mechanisms underlying the processing of unexpected stimuli and their evoked pupil dilation response. To assess this qualitatively, we used an auditory oddball paradigm in which we presented subjects a sequence of the same sounds followed by occasional deviants while we measured their evoked pupil dilation response (PDR). We used deviants (a frequency deviant, a pink noise burst, a monkey vocalization and a whistle sound) which differed in the spectral composition and in their ability to induce arousal from the standard. Most deviants elicited a significant pupil dilation in both species with decreased peak latency and increased peak amplitude in monkeys compared to humans. A temporal Principal Component Analysis (PCA) revealed two components underlying the PDRs in both species. The early component is likely associated to the parasympathetic nervous system and the late component to the sympathetic nervous system, respectively. Taken together, the present study demonstrates a qualitative similarity between PDRs to unexpected auditory stimuli in macaque and human subjects suggesting that macaques can be a suitable model for investigating the neuronal bases of pupil dilation. However, the quantitative differences in PDRs between species need to be investigated in further comparative studies.

Download Full-text

Human and Human-Interfaced AI Interactions: Modulation of Human Male Autonomic Nervous System via Pupil Mimicry

Sensors ◽

10.3390/s21041028 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1028

Author(s):

Catherine Spicer ◽

Prashanna Khwaounjoo ◽

Yusuf Ozgur Cakmak

Keyword(s):

Heart Rate ◽

Nervous System ◽

Parasympathetic Nervous System ◽

Pupil Dilation ◽

Physical Parameters ◽

Emotional States ◽

Virtual Humans ◽

Autonomic Functioning ◽

Technological Advances ◽

Pupil Constriction

Pupillary alterations in virtual humans induce neurophysiological responses within an observer. Technological advances have enabled rapid developments in artificial intelligence (AI), from verbal systems, to visual AI interfaces with the ability to express, and respond to emotional states of a user. Visual AI interfaces are able to change their physical parameters, such as pupil diameter. Pupillary changes can alter heart rate, however, effects on heart rate variability (HRV) are unknown. HRV, is an autonomic, non-conscious parameter which monitors sympathetic and parasympathetic nervous system (PNS) activity. N = 34 male participants aged between 19–33 were subjected to a number of conditions such as pupil dilation, constriction and blushing. The present research is the first to investigate the effects of virtual human interactions on human HRV. Outcomes of this study were obtained using eye tracking and HRV measurements. Pupil dilation relative to constriction presented in the female virtual partner induced a significant right pupillary diameter increase (p = 0.041) in human observers. Additionally, female virtual partner pupil constriction relative to dilation induced a significant increase in participants’ PNS HRV response (p = 0.036). These findings indicate the ability of a female virtual interaction partner to modulate parasympathetic autonomic functioning in young healthy male humans. This allows first insights into the effects of interacting with virtual AI interaction partners, on human autonomic functioning, and may aid development of future virtual humans, and their implementation into relevant clinical settings.

Download Full-text

Pupillometry as a reliable metric of auditory detection and discrimination across diverse stimulus paradigms in animal models

10.1101/2020.11.16.385286 ◽

2020 ◽

Author(s):

Pilar Montes-Lourido ◽

Manaswini Kar ◽

Isha Kumbam ◽

Srivatsun Sadagopan

Keyword(s):

Animal Models ◽

Human Subjects ◽

Great Promise ◽

Oddball Paradigm ◽

Full Potential ◽

Short Term ◽

Auditory Oddball ◽

Complex Stimuli ◽

Auditory Detection ◽

Wide Range

AbstractEstimates of detection and discrimination thresholds are often used to explore broad perceptual similarities between human subjects and animal models. Pupillometry shows great promise as a non-invasive, easily-deployable method of comparing human and animal thresholds. Using pupillometry, previous studies in animal models have obtained threshold estimates to simple stimuli such as pure tones, but have not explored whether similar pupil responses can be evoked by complex stimuli, what other stimulus contingencies might affect stimulus-evoked pupil responses, and if pupil responses can be modulated by experience or short-term training. In this study, we used an auditory oddball paradigm to estimate detection and discrimination thresholds across a wide range of stimuli in guinea pigs. We demonstrate that pupillometry yields reliable detection and discrimination thresholds across a range of simple (tones) and complex (conspecific vocalizations) stimuli; that pupil responses can be robustly evoked using different stimulus contingencies (low-level acoustic changes, or higher level categorical changes); and that pupil responses are modulated by short-term training. These results lay the foundation for using pupillometry as a high-throughput method of estimating thresholds in large experimental cohorts, and unveil the full potential of using pupillometry to explore broad similarities between humans and animal models.

Download Full-text

Real brains in virtual worlds: Validating a novel oddball paradigm in virtual reality

10.1101/749192 ◽

2019 ◽

Cited By ~ 1

Author(s):

Jonathan W. P. Kuziek ◽

Abdel R. Tayem ◽

Jennifer I. Burrell ◽

Eden X. Redman ◽

Jeff Murray ◽

...

Keyword(s):

Virtual Reality ◽

Virtual Worlds ◽

Spectral Composition ◽

Stimulus Presentation ◽

Event Related Potential ◽

Oddball Paradigm ◽

Auditory Oddball ◽

Oddball Task ◽

Eeg Data ◽

Head Mounted Displays

Electroencephalography (EEG) research is typically conducted in controlled laboratory settings. This limits the generalizability to real-world situations. Virtual reality (VR) sits as a transitional tool that provides tight experimental control with more realistic stimuli. To test the validity of using VR for event-related potential (ERP) research we used a well-established paradigm, the oddball task. For our first study, we compared VR to traditional, monitor-based stimulus presentation using visual and auditory oddball tasks while EEG data was recorded. We were able to measure ERP waveforms typically associated with such oddball tasks, namely the P3 and earlier N2 components, in both conditions. Our results suggest that ERPs collected using VR head mounted displays and typical monitors were comparable on measures of latency, amplitude, and spectral composition. In a second study, we implemented a novel depth-based oddball task and we were able to measure the typical oddball-related ERPs elicited by the presentation of near and far stimuli. Interestingly, we observed significant differences in early ERPs components between near and far stimuli, even after controlling for the effects of the oddball task. Current results suggest that VR can serve as a valid means of stimulus presentation in novel or otherwise inaccessible environments for EEG experimentation. We demonstrated the capability of a depth-based oddball in reliably eliciting a P3 waveform. We also found an interaction between the depth at which objects are presented and early ERP responses. Further research is warranted to better explain this influence of depth on the EEG and ERP activity.

Download Full-text

The Pupil Dilation Response During Speech Perception in Dark and Light: The Involvement of the Parasympathetic Nervous System in Listening Effort

Trends in Hearing ◽

10.1177/2331216518816603 ◽

2018 ◽

Vol 22 ◽

pp. 233121651881660 ◽

Cited By ~ 2

Author(s):

Yang Wang ◽

Sophia E. Kramer ◽

Dorothea Wendt ◽

Graham Naylor ◽

Thomas Lunner ◽

...

Keyword(s):

Nervous System ◽

Speech Perception ◽

Parasympathetic Nervous System ◽

Pupil Dilation ◽

Listening Effort

Download Full-text

NMDA receptor blockade causes selective prefrontal disinhibition in a roving auditory oddball paradigm

10.1101/133371 ◽

2017 ◽

Cited By ~ 1

Author(s):

Richard E Rosch ◽

Ryszard Auksztulewicz ◽

Pui Duen Leung ◽

Karl J Friston ◽

Torsten Baldeweg

Keyword(s):

Auditory Processing ◽

Human Subjects ◽

Network Models ◽

Inhibitory Interneuron ◽

Controlled Study ◽

Oddball Paradigm ◽

Double Blind ◽

Auditory Oddball ◽

Specific Effects ◽

Auditory Oddball Paradigm

N-methyl-D-aspartate receptors (NMDARs) are expressed widely throughout the human cortex. Yet disturbances in NMDAR transmission - as implicated in patients with schizophrenia or pharmacologically induced - can cause a regionally specific set of electrophysiological effects. Here, we present a double-blind placebo-controlled study of the effects of the NMDAR blocker ketamine in human volunteers. We employ a marker of auditory learning and putative synaptic plasticity - the mismatch negativity - in a roving auditory oddball paradigm. Using recent advances in Bayesian modelling of group effects in dynamic causal modelling, we fit biophysically plausible network models of the auditory processing hierarchy to whole-scalp evoked response potential recordings. This allowed us to identify the regionally specific effects of ketamine in a distributed network of interacting cortical sources. Under placebo, our analysis replicated previous findings regarding the effects of stimulus repetition and deviance on connectivity within the auditory hierarchy. Crucially, we show that the effect of ketamine is best explained as a selective change in intrinsic inhibition, with a pronounced ketamine-induced reduction of inhibitory interneuron connectivity in frontal sources. These results are consistent with findings from invasive recordings in animal models exposed to NMDAR blockers, and provide evidence that inhibitory-interneuron specific NMDAR dysfunction may be sufficient to explain electrophysiological abnormalities of sensory learning induced by ketamine in human subjects.

Download Full-text

Event-related transcutaneous vagus nerve stimulation modulates behaviour and pupillary responses during an auditory oddball task

10.31234/osf.io/kwd67 ◽

2021 ◽

Author(s):

Ruben Azevedo ◽

Gianluca Finotti ◽

Daniele Di Lernia ◽

Valerio Villani ◽

Manos Tsakiris

Keyword(s):

Vagus Nerve ◽

Cognitive Processes ◽

Nerve Stimulation ◽

Vagus Nerve Stimulation ◽

Temporal Dynamics ◽

Pupil Dilation ◽

Oddball Paradigm ◽

Auditory Oddball ◽

Transcutaneous Vagus Nerve Stimulation ◽

Pupillary Responses

Transcutaneous auricular vagus nerve stimulation (taVNS) is a neuromodulatory technique that is thought to activate the Locus Coeruleus-Noradrenaline (LC-NA) system. Standard taVNS protocols consist of the administration of intermittent or continuous stimulation over long periods. However, there is currently limited understanding of temporal dynamics of taVNS modulation of cognitive processes, as well as its mechanisms of action. We argue that novel stimulation approaches, informed by established theories of the LC-NA system, are needed to further our understanding of the neurocognitive underpinnings of taVNS. In this pre-registered study, we tested whether an “event-related” taVNS protocol can modulate the LC-NA system. In a within-subject design (single session) we delivered brief trains of taVNS (3 seconds) during an auditory oddball paradigm. The taVNS was time-locked to the target stimuli and randomly interleaved with sham stimulation. Response times (RT) and stimuli-driven pupillary diameter (PD) were used as indices of LC-NA activity. Results revealed that active taVNS increased RT to targets, as compared to sham trials. Notably, in line with current theories of LC-NA functioning, taVNS modulation of target-related pupil dilation depended on pre-stimulation PD, an index of tonic LC-NA activity. In particular, active (vs. sham) taVNS was associated with smaller pupil dilation in trials where the baseline PD was small. These results demonstrate, for the first time, the effectiveness of brief event-related taVNS in the modulation of cognitive processes and highlight the importance of using pupil size as an index of tonic and phasic LC-NA activity.

Download Full-text

Pupillometry as a reliable metric of auditory detection and discrimination across diverse stimulus paradigms in animal models

Scientific Reports ◽

10.1038/s41598-021-82340-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Pilar Montes-Lourido ◽

Manaswini Kar ◽

Isha Kumbam ◽

Srivatsun Sadagopan

Keyword(s):

Animal Models ◽

Human Subjects ◽

Great Promise ◽

Oddball Paradigm ◽

Full Potential ◽

Short Term ◽

Auditory Oddball ◽

Complex Stimuli ◽

Auditory Detection ◽

Wide Range

AbstractEstimates of detection and discrimination thresholds are often used to explore broad perceptual similarities between human subjects and animal models. Pupillometry shows great promise as a non-invasive, easily-deployable method of comparing human and animal thresholds. Using pupillometry, previous studies in animal models have obtained threshold estimates to simple stimuli such as pure tones, but have not explored whether similar pupil responses can be evoked by complex stimuli, what other stimulus contingencies might affect stimulus-evoked pupil responses, and if pupil responses can be modulated by experience or short-term training. In this study, we used an auditory oddball paradigm to estimate detection and discrimination thresholds across a wide range of stimuli in guinea pigs. We demonstrate that pupillometry yields reliable detection and discrimination thresholds across a range of simple (tones) and complex (conspecific vocalizations) stimuli; that pupil responses can be robustly evoked using different stimulus contingencies (low-level acoustic changes, or higher level categorical changes); and that pupil responses are modulated by short-term training. These results lay the foundation for using pupillometry as a reliable method of estimating thresholds in large experimental cohorts, and unveil the full potential of using pupillometry to explore broad similarities between humans and animal models.

Download Full-text

EFFECTS OF DIFFERENT DURATION OF TRADITIONAL THAI MASSAGE ON PARASYMPATHETIC NERVOUS SYSTEM

International Journal of Geomate ◽

10.21660/2016.28.1343 ◽

2016 ◽

Author(s):

Thanarat Sripongngam

Keyword(s):

Nervous System ◽

Parasympathetic Nervous System

Download Full-text

Daily inhalation of hydrogen gas has a blood pressure-lowering effect in a rat model of hypertension

Scientific Reports ◽

10.1038/s41598-020-77349-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Kazuhisa Sugai ◽

Tomoyoshi Tamura ◽

Motoaki Sano ◽

Shizuka Uemura ◽

Masahiko Fujisawa ◽

...

Keyword(s):

Blood Pressure ◽

Nervous System ◽

Parasympathetic Nervous System ◽

Pressure Control ◽

Hydrogen Gas ◽

Blood Pressure Lowering ◽

Blood Pressure Lowering Effect ◽

Night Time ◽

Lowering Effect ◽

Pressure Lowering

AbstractA recent clinical study demonstrated that haemodialysis with a dialysate containing hydrogen (H2) improves blood pressure control in end-stage kidney disease. Herein, we examined whether H2 has a salutary effect on hypertension in animal models. We subjected 5/6 nephrectomised rats to inhalation of either H2 (1.3% H2 + 21% O2 + 77.7% N2) or control (21% O2 + 79% N2) gas mixture for 1 h per day. H2 significantly suppressed increases in blood pressure after 5/6 nephrectomy. The anti-hypertensive effect of H2 was also confirmed in rats in a stable hypertensive state 3 weeks after nephrectomy. To examine the detailed effects of H2 on hypertension, we used an implanted telemetry system to continuously monitor blood pressure. H2 exerted an anti-hypertensive effect not only during daytime rest, but also during night-time activities. Spectral analysis of blood pressure variability revealed that H2 improved autonomic imbalance, namely by suppressing the overly active sympathetic nervous system and augmenting parasympathetic nervous system activity; these effects co-occurred with the blood pressure-lowering effect. In conclusion, 1-h daily exposure to H2 exerts an anti-hypertensive effect in an animal model of hypertension.

Download Full-text