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Acta Psychologica Oct 2021The startle reflex has been suggested to operate as a psychophysiological marker of psychopathic personality, based on findings from studies using a range of different... (Review)
Review
The startle reflex has been suggested to operate as a psychophysiological marker of psychopathic personality, based on findings from studies using a range of different methodologies and participant samples. The present review aims at synthesizing existing evidence of the relationship between psychopathy and the startle reflex across task paradigms, psychopathic personality subtypes and subdimensions, participant samples (i.e., incarcerated/ clinical or non-offenders), and age groups using the triarchic model of psychopathy as a frame of reference. Systematic literature searches were conducted up until the 24th of March 2020 in PubMed, PsycINFO, and Web of Science. A total of 2311 potential studies were identified, out of which 40 met relevancy and quality criteria. Results indicate that reduced aversive startle potentiation is associated with psychopathic personality in general, but clusters of traits relating to the triarchic model constructs of boldness and meanness in particular. Available evidence suggest that startle paradigms could be meaningful for differentiating individuals with and without psychopathic personality. Findings support suggestions of psychopathic personality as a multifaceted, rather than a unitary construct. Reduced aversive startle potentiation has also been found in relation to psychopathic features in child-aged samples but work of this kind is limited and more research is needed. Future studies should focus on greater consistency in task paradigms and analytic strategies to enhance the capacity to compare and integrate findings across studies.
Topics: Adolescent; Affect; Aged; Antisocial Personality Disorder; Child; Humans; Reflex, Startle; Young Adult
PubMed: 34628215
DOI: 10.1016/j.actpsy.2021.103427 -
Pediatric Neurology Jul 2022Hereditary hyperekplexia (HPX) is a genetic neurodevelopmental disorder recently defined by the triad of (1) neonatal hypertonia, (2) excessive startle reflexes, and (3)... (Review)
Review
Hereditary hyperekplexia (HPX) is a genetic neurodevelopmental disorder recently defined by the triad of (1) neonatal hypertonia, (2) excessive startle reflexes, and (3) generalized stiffness following the startle. Defects in GLRA1 are the most common cause of HPX, inherited both in an autosomal dominant and autosomal recessive manner. GLRA1 mutations can also cause milder phenotypes in the startle syndromes spectrum, but the prevalence is uncertain and no clear genotype-phenotype correlation has emerged yet. Moreover, the prevalence of neurodevelopmental outcomes has not been clearly defined. Here we report a new family of patients with a typical HPX phenotype, linked to a novel GLRA1 mutation, inherited with a recessive pattern. We then perform a systematic review of the literature of GLRA1-related HPX, describing the main epidemiological features of 210 patients. We found that GLRA1-related phenotypes do not necessarily fulfill the current criteria for HPX, including also milder and later-onset phenotypes. Among clinical features of the disease, neurodevelopmental issues were reported in a third of the sample; interestingly, we found that these problems, particularly when severe, were more common in homozygous than in heterozygous patients. Additional clinical and preclinical studies are needed to define predictors of adverse neurodevelopmental outcomes and underlying mechanisms.
Topics: Humans; Muscle Rigidity; Phenotype; Receptors, Glycine; Reflex, Startle; Stiff-Person Syndrome
PubMed: 35636282
DOI: 10.1016/j.pediatrneurol.2022.05.002 -
Neuroscience and Biobehavioral Reviews Aug 2019Startle reflex potentiation versus startle attenuation to unpleasant versus pleasant stimuli likely reflect priming of the defensive versus appetitive motivational...
Startle reflex potentiation versus startle attenuation to unpleasant versus pleasant stimuli likely reflect priming of the defensive versus appetitive motivational systems, respectively. This review summarizes and systemizes the literature on affective startle modulation related to psychopathologies with the aim to reveal underlying mechanisms across psychopathologies. We found evidence for psychopathologies characterized by increased startle potentiation to unpleasant stimuli (anxiety disorders), decreased startle potentiation to unpleasant stimuli (psychopathy), decreased startle attenuation to pleasant stimuli (ADHD), as well as a general hyporeactivity to affective stimuli (depression). Increased versus decreased startle responses to disorder-specific stimuli characterize specific phobia and drug dependence. No psychopathology is characterized by increased startle attenuation to standard pleasant stimuli or a general hyperreactivity to affective stimuli. This review indicates that the defensive and the appetitive systems operate independently mostly in accordance with the motivational priming hypothesis and that affective startle modulation is a highly valuable paradigm to unraveling dysfunctions of the defensive and appetitive systems in psychopathologies as requested by the Research Domain Criteria initiative.
Topics: Affect; Antisocial Personality Disorder; Anxiety Disorders; Appetitive Behavior; Attention Deficit Disorder with Hyperactivity; Avoidance Learning; Depressive Disorder; Humans; Motivation; Reflex, Abnormal; Reflex, Startle
PubMed: 31129237
DOI: 10.1016/j.neubiorev.2019.05.019 -
Human Brain Mapping Nov 2021Startle reflex is modulated when a weaker sensory stimulus ("prepulse") precedes a startling stimulus ("pulse"). Prepulse Inhibition (PPI) is the attenuation of the...
Startle reflex is modulated when a weaker sensory stimulus ("prepulse") precedes a startling stimulus ("pulse"). Prepulse Inhibition (PPI) is the attenuation of the startle reflex (prepulse precedes pulse by 30-500 ms), whereas Prepulse Facilitation (PPF) is the enhancement of the startle reflex (prepulse precedes pulse by 500-6000 ms). Here, we critically appraise human studies using functional neuroimaging to establish brain regions associated with PPI and PPF. Of 10 studies, nine studies revealed thalamic, striatal and frontal lobe activation during PPI in healthy groups, and activation deficits in the cortico-striato-pallido-thalamic circuitry in schizophrenia (three studies) and Tourette Syndrome (two studies). One study revealed a shared network for PPI and PPF in frontal regions and cerebellum, with PPF networks recruiting superior medial gyrus and cingulate cortex. The main gaps in the literature are (i) limited PPF research and whether PPI and PPF operate on separate/shared networks, (ii) no data on sex differences in neural underpinnings of PPI and PPF, and (iii) no data on neural underpinnings of PPI and PPF in other clinical disorders.
Topics: Functional Neuroimaging; Humans; Perception; Prepulse Inhibition; Reflex, Startle; Schizophrenia; Sensation; Tourette Syndrome
PubMed: 34414633
DOI: 10.1002/hbm.25631 -
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 -
The World Journal of Biological... Jul 2021Startle response is an objective physiological measure integral to the human defense system and a promising target for endophenotype investigations of anxiety. Given the...
OBJECTIVES
Startle response is an objective physiological measure integral to the human defense system and a promising target for endophenotype investigations of anxiety. Given the alterations in startle reactivity observed among anxiety and related disorders, we searched for genetic variants associated with startle reactivity as they may be further involved in pathological anxiety risk.
METHODS
A systematic literature review was performed to identify genetic variants associated with startle reactivity in humans, specifically baseline and fear- or anxiety-potentiated startle.
RESULTS
The polymorphisms Val66Met (rs6265) from brain-derived neurotrophic factor (), Val158Met (rs4680) from catechol-O-methyltransferase (), and the serotonin transporter-linked polymorphic region (5-HTTLPR) from the serotonin transporter gene () were most commonly studied in human startle. In addition, several other genetic variants have also been identified as potential candidates that warrant further research, especially given their novelty in in the context of anxiety.
CONCLUSIONS
Similar to psychiatric genetic studies, the studies on startle reactivity primarily focus on candidate genes and are plagued by non-replication. Startle reactivity is a promising endophenotype that requires concerted efforts to collect uniformly assessed, large, well-powered samples and hypothesis-free genome-wide strategies. To further support startle as an endophenotype for anxiety, this review suggests advanced genetic strategies for startle research.
Topics: Anxiety; Anxiety Disorders; Catechol O-Methyltransferase; Endophenotypes; Genotype; Humans; Reflex, Startle; Serotonin Plasma Membrane Transport Proteins
PubMed: 33040669
DOI: 10.1080/15622975.2020.1834619 -
Przeglad Lekarski 2016The aim of the study was to establish current scope of knowledge regarding associations between neurophysiological functioning, neuropsychology and psychoterapy. (Review)
Review
AIM
The aim of the study was to establish current scope of knowledge regarding associations between neurophysiological functioning, neuropsychology and psychoterapy.
MATERIAL AND METHODS
A systematic review was performed including 93 publications from Science Server, which contains the collections of Elsevier, Springer Journals, SCI-Ex/ICM, MEDLINE/PubMed, and SCOPUS. The works have been selected basing on following key words: 'neuropsychology, neurocognitive correlates, electrodermal response, event related potential, EEG, pupillography, electromiography' out of papers published between 2004-2015.
RESULTS
Present reports on the use of neurophysiological methods in psychology can be divided into two areas: experimental research and research of the practical use of conditioning techniques and biofeedback in the treatment of somatic disease. Among the experimental research the following have been distinguished: research based on the startle reflex, physiological reaction to novelty, stress, type/amount of cognitive load and physiological correlates of emotion; research on the neurophysiological correlates of mental disorders, mostly mood and anxiety disorders, and neurocognitive correlates: of memory, attention, learning and intelligence. Among papers regarding the use of neurophysiological methods in psychology two types are the most frequent: on the mechanisms of biofeedback, related mainly to neuro- feedback, which is a quickly expanding method of various attention and mental disorders'treatment, and also research of the use of conditioning techniques in the treatment of mental disorders, especially depression and anxiety. A special place among all the above is taken by the research on electrophysiological correlates of psychotherapy, aiming to differentiate between the efficacy of various psychotherapeutic schools (the largest amount of publications regard the efficacy of cognitive-behavioral psychotherapy) in patients of different age groups and different diagnosis.
Topics: Anxiety Disorders; Depressive Disorder; Electroencephalography; Electromyography; Evoked Potentials; Humans; Neurophysiology; Neuropsychology; Psychotherapy
PubMed: 27349052
DOI: No ID Found -
Behaviour Research and Therapy Jan 2019Fear extinction studies in youth have yielded mixed results due to developmental processes and variations in design, methodology and dependent measures. This systematic...
The need for standards in the design of differential fear conditioning and extinction experiments in youth: A systematic review and recommendations for research on anxiety.
Fear extinction studies in youth have yielded mixed results due to developmental processes and variations in design, methodology and dependent measures. This systematic review focused on studies with healthy youth between 2 and 17 years of age to identify experimental parameters of studies documenting extinction effects. Thirty-five studies met inclusion criteria and the following themes emerged (a) some studies employed parameters and task demands that are complex and require active participant involvement whereas others involved simple stimulus configurations and passive participant involvement, and (b) variation exists among dependent measures in units of measurement, timing and type of measurement. The review identified that studies using geometric shape conditioned stimuli (CS) paired with a tone unconditioned stimulus (US) (e.g., metal scraping on slate), as well as face CSs with a scream US produced the most reliable extinction effects, although the latter combination may be associated with higher drop-out than shape CSs and a tone US. The most commonly used and effective dependent measures for revealing extinction effects were skin conductance responses (SCR) and subjective ratings (SR) of CS valence, fearfulness and arousal. Fear potentiated startle (FPS) blink reflexes were also an effective but less commonly used measure. It is recommended that future studies use shape CSs and the metal scraping on slate US in studies involving children and either shape CSs and the metal scraping on slate US or face CSs paired with a scream US with adolescents. It is also recommended that US expectancy ratings and CS evaluations are assessed trial-by-trial and between-phase, and that startle-eliciting stimuli to measure startle blink reflexes are delivered on every second trial per CS so that SCR and FPS can be examined. However, further research is required to determine whether increased participant involvement due to providing trial-by-trial and between-phase ratings of the CSs and US differentially influences responding, particularly in children relative to adolescents and adults.
Topics: Adolescent; Anxiety; Arousal; Child; Child, Preschool; Conditioning, Classical; Extinction, Psychological; Fear; Humans; Reflex, Startle; Research Design
PubMed: 30502721
DOI: 10.1016/j.brat.2018.11.009 -
Frontiers in Psychiatry 2020Deficits in the gating of sensory stimuli, i.e., the ability to suppress the processing of irrelevant sensory input, are considered to play an important role in the...
Deficits in the gating of sensory stimuli, i.e., the ability to suppress the processing of irrelevant sensory input, are considered to play an important role in the pathogenesis of several neuropsychiatric disorders, in particular schizophrenia. Gating is disrupted both in schizophrenia patients and their unaffected relatives, suggesting that gating deficit may represent a biomarker associated with a genetic liability to the disorder. To assess the strength of the evidence for the etiopathogenetic links between genetic variation, gating efficiency, and schizophrenia, we carried out a systematic review of human genetic association studies of sensory gating (suppression of the P50 component of the auditory event-related brain potential) and sensorimotor gating (prepulse inhibition of the acoustic startle response). Sixty-three full-text articles met the eligibility criteria for inclusion in the review. In total, 117 genetic variants were reported to be associated with gating functions: 33 variants for sensory gating, 80 variants for sensorimotor gating, and four variants for both sensory and sensorimotor gating. However, only five of these associations (four for prepulse inhibition-CHRNA3 rs1317286, COMT rs4680, HTR2A rs6311, and TCF4 rs9960767, and one for P50 suppression-CHRNA7 rs67158670) were consistently replicated in independent samples. Although these variants and genes were all implicated in schizophrenia in research studies, only two polymorphisms ( rs6311 and rs9960767) were also reported to be associated with schizophrenia at a meta-analytic or genome-wide level of evidence. Thus, although gating is widely considered as an important endophenotype of schizophrenia, these findings demonstrate that evidence for a common genetic etiology of impaired gating functions and schizophrenia is yet unsatisfactory, warranting further studies in this field.
PubMed: 33324248
DOI: 10.3389/fpsyt.2020.550225 -
Journal of Neurophysiology Apr 2022Control of limb movements may be impaired after stroke due to the loss of connectivity between the cerebral cortex and spinal cord. A notion to improve motor function in... (Meta-Analysis)
Meta-Analysis Review
Control of limb movements may be impaired after stroke due to the loss of connectivity between the cerebral cortex and spinal cord. A notion to improve motor function in stroke survivors is to use alternate motor fibers, such as the reticulospinal tract (RST), which originate from the brainstem and terminate at different levels of spinal cord. One way of targeting the RST is to use a "StartReact" protocol to foster premature release of a preplanned movement in response to a startling stimulus. Our aim was to find support for the preservation of such StartReact effect in stroke survivors. We conducted a systematic review with meta-analysis of literature published in English up to September 2020, to explore differences in motor responses to startling stimuli in StartReact effects. Protocol of the study was registered (PROSPERO Registration No. CRD42020191581). PubMed, Google Scholar, Web of Science, PsycINFO, and Science Direct were searched for relevant literature. The meta-analysis contained six studies involving a total of 151 stroke and healthy participants. Muscle onset latency data were extracted from the qualifying studies and compared using RevMan. StartReact effect was present in both stroke and healthy groups, represented by shortened muscle onset latency when startling stimulus was present. There was considerable heterogeneity of the outcome measures, which was attributed to the range of motor impairments among stroke survivors and methodologies used. Our findings support the notion of preservation of preprogramming ability and suitability of RST and StartReact effect for motor rehabilitation following stroke.
Topics: Acoustic Stimulation; Electromyography; Humans; Reflex, Startle; Stroke; Stroke Rehabilitation; Survivors
PubMed: 35235444
DOI: 10.1152/jn.00392.2021