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The Journal of Pain Mar 2015This study investigated the effects of a threatening and a safe social context on learning pain-related fear, a key factor in the development and maintenance of chronic...
UNLABELLED
This study investigated the effects of a threatening and a safe social context on learning pain-related fear, a key factor in the development and maintenance of chronic pain. We measured self-reported pain intensity, pain expectancy, pain-related fear (verbal ratings and eyeblink startle responses), and behavioral measures of avoidance (movement-onset latency and duration) using an established differential voluntary movement fear conditioning paradigm. Participants (N = 42) performed different movements with a joystick: during fear acquisition, movement in one direction (CS+) was followed by a painful stimulus (pain-US) whereas movement in another direction (CS-) was not. For participants in the threat group, an angry face was continuously presented in the background during the task, whereas in the safe group, a happy face was presented. During the extinction phase the pain-US was omitted. As compared to the safe social context, a threatening social context led to increased contextual fear and facilitated differentiation between CS+ and CS- movements regarding self-reported pain expectancy, fear of pain, eyeblink startle responses, and movement-onset latency. In contrast, self-reported pain intensity was not affected by social context. These data support the modulation of pain-related fear by social context.
PERSPECTIVE
A threatening social context leads to stronger acquisition of (pain-related) fear and simultaneous contextual fear but does not affect pain intensity ratings. This knowledge may aid in the prevention of chronic pain and anxiety disorders and shows that social context might modulate pain-related fear without immediately affecting pain intensity itself.
Topics: Adolescent; Adult; Blinking; Conditioning, Psychological; Face; Facial Expression; Fear; Female; Humans; Male; Pain; Photic Stimulation; Psychological Tests; Psychomotor Performance; Reaction Time; Reflex, Startle; Self Report; Social Behavior; Young Adult
PubMed: 25510542
DOI: 10.1016/j.jpain.2014.11.014 -
PLoS Computational Biology Feb 2020The limited capacity of recent memory inevitably leads to partial memory of past stimuli. There is also evidence that behavioral and neural responses to novel or rare...
The limited capacity of recent memory inevitably leads to partial memory of past stimuli. There is also evidence that behavioral and neural responses to novel or rare stimuli are dependent on one's memory of past stimuli. Thus, these responses may serve as a probe of different individuals' remembering and forgetting characteristics. Here, we utilize two lossy compression models of stimulus sequences that inherently involve forgetting, which in addition to being a necessity under many conditions, also has theoretical and behavioral advantages. One model is based on a simple stimulus counter and the other on the Information Bottleneck (IB) framework which suggests a more general, theoretically justifiable principle for biological and cognitive phenomena. These models are applied to analyze a novelty-detection event-related potential commonly known as the P300. The trial-by-trial variations of the P300 response, recorded in an auditory oddball paradigm, were subjected to each model to extract two stimulus-compression parameters for each subject: memory length and representation accuracy. These parameters were then utilized to estimate the subjects' recent memory capacity limit under the task conditions. The results, along with recently published findings on single neurons and the IB model, underscore how a lossy compression framework can be utilized to account for trial-by-trial variability of neural responses at different spatial scales and in different individuals, while at the same time providing estimates of individual memory characteristics at different levels of representation using a theoretically-based parsimonious model.
Topics: Acoustic Stimulation; Adult; Electroencephalography; Evoked Potentials; Female; Humans; Male; Memory; Reflex, Startle
PubMed: 32012146
DOI: 10.1371/journal.pcbi.1007065 -
Nature Communications Nov 2021The reticulotegmental nucleus (RtTg) has long been recognized as a crucial component of brainstem reticular formation (RF). However, the function of RtTg and its...
The reticulotegmental nucleus (RtTg) has long been recognized as a crucial component of brainstem reticular formation (RF). However, the function of RtTg and its related circuits remain elusive. Here, we report a role of the RtTg in startle reflex, a highly conserved innate defensive behaviour. Optogenetic activation of RtTg neurons evokes robust startle responses in mice. The glutamatergic neurons in the RtTg are significantly activated during acoustic startle reflexes (ASR). Chemogenetic inhibition of the RtTg glutamatergic neurons decreases the ASR amplitudes. Viral tracing reveals an ASR neural circuit that the cochlear nucleus carrying auditory information sends direct excitatory innervations to the RtTg glutamatergic neurons, which in turn project to spinal motor neurons. Together, our findings describe a functional role of RtTg and its related neural circuit in startle reflexes, and demonstrate how the RF connects auditory system with motor functions.
Topics: Acoustic Stimulation; Animals; Auditory Pathways; Brain Stem; Cochlear Nerve; Mice; Mice, Inbred C57BL; Reflex, Startle
PubMed: 34737329
DOI: 10.1038/s41467-021-26723-9 -
Psychophysiology Oct 2022Sensitivity to uncertain threat (U-threat) is a clinically important individual difference factor in multiple psychopathologies. Recent studies have implicated a...
Sensitivity to uncertain threat (U-threat) is a clinically important individual difference factor in multiple psychopathologies. Recent studies have implicated a specific frontolimbic circuit as a key network involved in the anticipation of aversive stimuli. In particular, the insula, thalamus, and dorsal anterior cingulate cortex (dACC) have recently been found to be robustly activated by anticipation of U-threat. However, no study to date has examined the association between U-threat reactivity and structural brain volume. In the present study, we utilized a pooled sample of 186 young adult volunteers who completed a structural MRI scan and the well-validated No-Predictable-Unpredictable (NPU) threat of electric shock task. Startle eyeblink potentiation was collected during the NPU task as an objective index of aversive reactivity. ROI-based analyses revealed that increased startle reactivity to U-threat was associated with reduced gray matter volume in the right insula and bilateral thalamus, but not the dACC. These results add to a growing literature implicating the insula and thalamus as core nodes involved in individual differences in U-threat reactivity.
Topics: Anxiety; Blinking; Fear; Gyrus Cinguli; Humans; Reflex, Startle; Uncertainty; Young Adult
PubMed: 35579909
DOI: 10.1111/psyp.14074 -
Psychophysiology Aug 2018Despite its evolutionary and clinical significance, appetitive conditioning has been rarely investigated in humans. It has been proposed that this discrepancy might stem...
Despite its evolutionary and clinical significance, appetitive conditioning has been rarely investigated in humans. It has been proposed that this discrepancy might stem from the difficulty in finding suitable appetitive stimuli that elicit strong physiological responses. However, this might also be due to a possible lack of sensitivity of the psychophysiological measures commonly used to index human appetitive conditioning. Here, we investigated whether the postauricular reflex-a vestigial muscle microreflex that is potentiated by pleasant stimuli relative to neutral and unpleasant stimuli-may provide a valid psychophysiological indicator of appetitive conditioning in humans. To this end, we used a delay differential appetitive conditioning procedure, in which a neutral stimulus was contingently paired with a pleasant odor (CS+), while another neutral stimulus was not associated with any odor (CS-). We measured the postauricular reflex, the startle eyeblink reflex, and skin conductance response (SCR) as learning indices. Taken together, our results indicate that the postauricular reflex was potentiated in response to the CS+ compared with the CS-, whereas this potentiation extinguished when the pleasant odor was no longer delivered. In contrast, we found no evidence for startle eyeblink reflex attenuation in response to the CS+ relative to the CS-, and no effect of appetitive conditioning was observed on SCR. These findings suggest that the postauricular reflex is a sensitive measure of human appetitive conditioning and constitutes a valuable tool for further shedding light on the basic mechanisms underlying emotional learning in humans.
Topics: Acoustic Stimulation; Adolescent; Adult; Appetitive Behavior; Blinking; Conditioning, Classical; Ear Auricle; Female; Galvanic Skin Response; Humans; Male; Odorants; Physical Stimulation; Reflex; Reflex, Startle; Young Adult
PubMed: 29524234
DOI: 10.1111/psyp.13073 -
Brain and Behavior May 2024Chronic adolescent stress profoundly affects prefrontal cortical networks regulating top-down behavior control. However, the neurobiological pathways contributing to...
INTRODUCTION
Chronic adolescent stress profoundly affects prefrontal cortical networks regulating top-down behavior control. However, the neurobiological pathways contributing to stress-induced alterations in the brain and behavior remain largely unknown. Chronic stress influences brain growth factors and immune responses, which may, in turn, disrupt the maturation and function of prefrontal cortical networks. The tumor necrosis factor alpha-converting enzyme/a disintegrin and metalloproteinase 17 (TACE/ADAM17) is a sheddase with essential functions in brain maturation, behavior, and inflammatory responses. This study aimed to determine the impact of stress on the prefrontal cortex and whether TACE/ADAM17 plays a role in these responses.
METHODS
We used a Lewis rat model that incorporates critical elements of chronic psychosocial stress, such as uncontrollability, unpredictability, lack of social support, and re-experiencing of trauma.
RESULTS
Chronic stress during adolescence reduced the acoustic startle reflex and social interactions while increasing extracellular free water content and TACE/ADAM17 mRNA levels in the medial prefrontal cortex. Chronic stress altered various ethological behavioral domains in the observation home cages (decreased ingestive behaviors and increased walking, grooming, and rearing behaviors). A group of rats was injected intracerebrally either with a novel Accell™ SMARTpool TACE/ADAM17 siRNA or a corresponding siRNA vehicle (control). The RNAscope Multiplex Fluorescent v2 Assay was used to visualize mRNA expression. Automated puncta quantification and analyses demonstrated that TACE/ADAM17 siRNA administration reduced TACE/ADAM17 mRNA levels in the medial prefrontal cortex (59% reduction relative to control). We found that the rats that received prefrontal cortical TACE/ADAM17 siRNA administration exhibited altered eating patterns (e.g., increased food intake and time in the feeding zone during the light cycle).
CONCLUSION
This study supports that the prefrontal cortex is sensitive to adolescent chronic stress and suggests that TACE/ADAM17 may be involved in the brain responses to stress.
Topics: Animals; Male; Rats; ADAM17 Protein; Behavior, Animal; Prefrontal Cortex; Rats, Inbred Lew; Reflex, Startle; Stress, Psychological; Female
PubMed: 38715397
DOI: 10.1002/brb3.3482 -
Molecular Psychiatry Jun 2021Measuring animal behavior in the context of experimental manipulation is critical for modeling, and understanding neuropsychiatric disease. Prepulse inhibition of the...
Measuring animal behavior in the context of experimental manipulation is critical for modeling, and understanding neuropsychiatric disease. Prepulse inhibition of the acoustic startle response (PPI) is a behavioral phenomenon studied extensively for this purpose, but the results of PPI studies are often inconsistent. As a result, the utility of this phenomenon remains uncertain. Here, we deconstruct the phenomenon of PPI and confirm several limitations of the methodology traditionally utilized to describe PPI, including that the underlying startle response has a non-Gaussian distribution, and that the traditional PPI metric changes with different stimuli. We then develop a novel model that reveals PPI to be a combination of the previously appreciated scaling of the startle response, as well as a scaling of sound processing. Using our model, we find no evidence for differences in PPI in a rat model of Fragile-X Syndrome (FXS) compared with wild-type controls. These results in the rat provide a reliable methodology that could be used to clarify inconsistent PPI results in mice and humans. In contrast, we find robust differences between wild-type male and female rats. Our model allows us to understand the nature of these differences, and we find that both the startle-scaling and sound-scaling components of PPI are a function of the baseline startle response. Males and females differ specifically in the startle-scaling, but not the sound-scaling, component of PPI. These findings establish a robust experimental and analytical approach that has the potential to provide a consistent biomarker of brain function.
Topics: Acoustic Stimulation; Acoustics; Animals; Female; Fragile X Syndrome; Male; Mice; Prepulse Inhibition; Rats; Reflex, Startle
PubMed: 32144356
DOI: 10.1038/s41380-020-0703-y -
Biomedicine & Pharmacotherapy =... Oct 2020Diabetic retinopathy (DR) is progressive damage to the retina and it's caused by damage to the blood-retinal barrier. Quercetin has pleiotropic action like anti-oxidant,...
Diabetic retinopathy (DR) is progressive damage to the retina and it's caused by damage to the blood-retinal barrier. Quercetin has pleiotropic action like anti-oxidant, regulation cell cycle &vascular integrity, and preventive effect of neuroinflammation. The present study is designed to investigate the nano-formulation of quercetin (NQ) in a zebrafish model of DR. The DR was developed by a single intraperitoneal injection of streptozotocin (STZ; 350 mg/kg). The acceleration of retinopathy was made on 7 days of diabetic zebrafish by intravitreal injection of STZ (20 μL of 7 % w/v of STZ stock solution). The treatment of NQ (5 and 10 mg/kg; i.p.) was administered for 21 consecutive days. The reference control i.e., dexamethasone (DEX, 10 mg/kg; i.p.) was also administered for 21 consecutive days. The sign of DR was assessed by eyeball/body weight ratio, eyeball weight, optomotor response (OMR), startle response (SR), phototactic response (PTR), and escape response (ER). Furthermore, the biochemical changes like plasma glucose and homocysteine (HCY) levels; and eye retinal tissue lipid peroxidation, reduced glutathione (GSH), and arginase reductase (AR) activity levels were assessed. The NQ found to attenuate the effect of STZ induced DR along with the regulation of biochemical abnormalities. And, it also comparable with reference drug treatment i.e., DEX treated group. Hence, NQ can be used for the treatment of diabetic associated retinopathy and neurosensory disorder visits anti-hyperglycemic, regulation of homocysteine pathway, reduction of lipid peroxidation, and free radical scavenging actions.
Topics: Animals; Blood Glucose; Body Weight; Diabetes Mellitus, Experimental; Diabetic Retinopathy; Escape Reaction; Eye; Hypoglycemic Agents; Male; Nanomedicine; Organ Size; Quercetin; Reflex, Startle; Zebrafish
PubMed: 32745912
DOI: 10.1016/j.biopha.2020.110573 -
Psychopharmacology Nov 2023Fear conditioning is an important aspect in the pathophysiology of anxiety disorders. The fear-potentiated startle test is based on classical fear conditioning and over... (Meta-Analysis)
Meta-Analysis Review
RATIONALE AND OBJECTIVES
Fear conditioning is an important aspect in the pathophysiology of anxiety disorders. The fear-potentiated startle test is based on classical fear conditioning and over the years, a broad range of drugs have been tested in this test. Synthesis of the available data may further our understanding of the neurotransmitter systems that are involved in the expression of conditioned fear.
METHODS
Following a comprehensive search in Medline and Embase, we included 68 research articles that reported on 103 drugs, covering 56 different drug classes. The systematic review was limited to studies using acute, systemic drug administration in naive animals.
RESULTS
Qualitative data synthesis showed that most clinically active anxiolytics, but not serotonin-reuptake inhibitors, reduced cued fear. Anxiogenic drugs increased fear potentiation in 35% of the experiments, reduced fear potentiation in 29% of the experiments, and were without effect in 29% of the experiments. Meta-analyses could be performed for five drug classes and showed that benzodiazepines, buspirone, 5-HT agonists, 5-HT antagonists, and mGluR2,3 agonists reduced cued conditioned fear. The non-cued baseline startle response, which may reflect contextual anxiety, was only significantly reduced by benzodiazepines and 5-HT antagonists. No associations were found between drug effects and methodological characteristics, except for strain.
CONCLUSIONS
The fear-potentiated startle test appears to have moderate to high predictive validity and may serve as a valuable tool for the development of novel anxiolytics. Given the limited available data, the generally low study quality and high heterogeneity additional studies are warranted to corroborate the findings of this review.
Topics: Animals; Anti-Anxiety Agents; Serotonin; Fear; Anxiety; Benzodiazepines; Reflex, Startle
PubMed: 36651922
DOI: 10.1007/s00213-022-06307-1 -
Current Biology : CB Nov 2016Jumping spiders (Salticidae) are famous for their visually driven behaviors [1]. Here, however, we present behavioral and neurophysiological evidence that these animals...
Jumping spiders (Salticidae) are famous for their visually driven behaviors [1]. Here, however, we present behavioral and neurophysiological evidence that these animals also perceive and respond to airborne acoustic stimuli, even when the distance between the animal and the sound source is relatively large (∼3 m) and with stimulus amplitudes at the position of the spider of ∼65 dB sound pressure level (SPL). Behavioral experiments with the jumping spider Phidippus audax reveal that these animals respond to low-frequency sounds (80 Hz; 65 dB SPL) by freezing-a common anti-predatory behavior characteristic of an acoustic startle response. Neurophysiological recordings from auditory-sensitive neural units in the brains of these jumping spiders showed responses to low-frequency tones (80 Hz at ∼65 dB SPL)-recordings that also represent the first record of acoustically responsive neural units in the jumping spider brain. Responses persisted even when the distances between spider and stimulus source exceeded 3 m and under anechoic conditions. Thus, these spiders appear able to detect airborne sound at distances in the acoustic far-field region, beyond the near-field range often thought to bound acoustic perception in arthropods that lack tympanic ears (e.g., spiders) [2]. Furthermore, direct mechanical stimulation of hairs on the patella of the foreleg was sufficient to generate responses in neural units that also responded to airborne acoustic stimuli-evidence that these hairs likely play a role in the detection of acoustic cues. We suggest that these auditory responses enable the detection of predators and facilitate an acoustic startle response. VIDEO ABSTRACT.
Topics: Acoustic Stimulation; Animals; Brain; Hearing; Reflex, Startle; Spiders
PubMed: 27746028
DOI: 10.1016/j.cub.2016.08.041