[A controlled alternating impulse generator with an end stage for adding positive-negative impulses].
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Cell Membrane↗
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Results for “Impulsivity”
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[Use of the AI-100 impulse analyzer for temporal analysis of neuronal impulse activity].
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Electrophysiology↗
The effect of Cavinton on impulse formation and impulse conduction of the heart.
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Adult↗
The effects of impulse level on the interaction between impulse and continuous noise.
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Animals↗
[Impulse cytophotometry in neoplasm prevention. The behavior of normal vaginal smears in the impulse cytophotometric histogram].
Evaluation of histograms of normal cervical and vaginal smears, produced by ""rapid flow through'' cytophotometry. Normal cytological cervical and vaginal smears were examined for their appearance in histograms in order to find criteria for the classification of ""normal non-pathological'' cytological slides. Simultaneously, the reliability of the standardized method for preparation of vaginal and cervical smears was checked. The diagrams and data produced by the histograph were also coded on line and analyzed by a computer; thus obtaining an objective mathematical analysis and avoiding errors due to subjective visual analysis of the histograms. The objective interpretation of histograms of normal vaginal smears is an important step to the realisation of automatic pre-screening.
Computers↗
Two models of impulsivity: relationship to personality traits and psychopathology.
BACKGROUND: Impulsivity is prominent in psychiatric disorders. Two dominant models of impulsivity are the reward-discounting model, where impulsivity is defined as inability to wait for a larger reward, and the rapid-response model, where impulsivity is defined as responding without adequate assessment of context. We have compared the role of these models of impulsivity in human psychopathology, based on the hypothesis that rapid-response impulsivity would be more strongly related to other aspects of psychopathology and to impulsivity as described by questionnaires. METHODS: We investigated relationships between personality and laboratory measures of impulsivity, and between these measures and clinical characteristics, in parents of adolescent subjects with disruptive behavioral disorders (DBDs) and matched control subjects. Diagnoses were rendered using the Structured Interview for DSM-IV. The Barratt Impulsiveness Scale (BIS) was used as a trait measure of impulsivity. Rapid-response impulsivity was assessed using a form of the Continuous Performance Test, the Immediate Memory-Delayed Memory Task (IMT/DMT). Reward-delay impulsivity was measured using two tasks where subjects could choose between smaller immediate or larger delayed rewards. RESULTS: Rapid-response, but not reward-delay impulsivity, was significantly higher in subjects with lifetime Axis I or Axis II diagnoses. Scores on the BIS were elevated in subjects with Axis I diagnoses and correlated significantly with both rapid-response and reward-delay tests, but more strongly with the former. Multiple regression showed that rapid-response, but not reward-delay performance or intelligence quotient, contributed significantly to BIS scores. Correlations were similar in parents of control subjects and of DBD subjects. CONCLUSIONS: These data suggest that measures of rapid-response impulsivity and of reward-delay impulsivity are both related to impulsivity as a personality characteristic. The relationship appears stronger, however, for rapid-response impulsivity, as measured by the IMT/DMT. Laboratory and personality measures of impulsivity appear to be related to risk of psychopathology.
Adult↗
An analysis of the effect of retinal ganglion cell impulses upon the firing probability of neurons in the dorsal lateral geniculate nucleus of the cat.
This study examines the probabilistic way in which LGN cells produce impulses. Simultaneous extracellular recordings were made from a single lateral geniculate nucleus (LGN) relay cell and the one retinal cell that triggered most of its impulses during vigorous responses. Impulses in the retinal train were classified as 'successful' in triggering an LGN impulse, or 'unsuccessful'. Similarly, the impulses in the LGN train were either 'Triggered' by a successful retinal impulse, or were 'Anonymous'. These impulses delimited various intervals whose distributions were compared to the relevant distribution of all intervals to determine whether short or long intervals tended to dominate in each case. Intervals between unsuccessful and successful impulses tended to be shorter than other retinal intervals, with their probability declining exponentially with duration. These data imply a decaying excitation produced by each impulse, but with a short refractory period following each Triggered impulse. Short intervals between Anonymous impulses were relatively common; Anonymous impulses thus lack the same refractoriness and tend to occur in bursts. The exponential excitation following an unsuccessful retinal impulse also facilitates Anonymous impulses, while Anonymous impulses (during visual stimulation) render the LGN slightly refractory for subsequent retinal impulses.
Action Potentials↗
Adaptive and maladaptive impulsivity, platelet monoamine oxidase (MAO) activity and risk-admitting in different types of risky drivers.
RATIONALE: Platelet monoamine oxidase (MAO) activity reflects serotonergic functioning associated with impulsive behaviour, but the significance of these associations to real-life impulsive behaviour in healthy subjects is not clear. OBJECTIVES: The present study explores impulsivity and platelet MAO activity among people with driving violations. MATERIALS AND METHODS: We compared facets of impulsivity and platelet MAO activity in 1,004 male drivers, out of whom 203 had been caught by the police driving drunk and 292 had been caught exceeding speed limits and committing other non-alcohol-related driving violations. Subjects with speeding and other non-alcohol-related violations were further divided according to their self-reported risk-admitting of exceeding speed limits. RESULTS: While drunk driving was associated only with maladaptive types of impulsivity, exceeding speed limits was associated with functional impulsivity and excitement seeking and, to a lesser degree, with dysfunctional impulsivity. Drunk drivers had lower platelet MAO activity. Risk-admitting high-risk drivers had higher platelet MAO activity, neuroticism-related impulsivity, dysfunctional impulsivity and excitement seeking compared to all other groups and higher functional impulsivity compared to controls. Risk-denying high-risk drivers had only higher functional impulsivity compared to controls. CONCLUSIONS: This study demonstrates different expressions of functional and dysfunctional impulsivity in behaviour. While platelet MAO activity is lower in alcohol-related risky behaviour, non-alcohol-related self-acknowledged risky behaviour is related to higher platelet MAO activity. Thus, deviance towards lower as well as higher end of central serotonergic functioning may lead to impulsive behaviour. While self-reported impulsivity did not correlate with MAO activity, both MAO activity and impulsivity were related to risky behaviour.
Adult↗
Excitatory actions of single impulses in single hair follicle afferent fibres on spinocervical tract neurones in the cat.
1. In cats under chloralose anaesthesia single dorsal root ganglion cells with axons innervating hair follicles were stimulated intracellularly to produce single impulses. At the same time single spinocervical tract (s.c.t.) neurones were recorded extracellularly, from their axons in the upper lumbar cord. 2. When the receptive field of the afferent fibre was contained within the impulse firing zone of the s.c.t. cell, a single afferent impulse increased the probability of firing of the neurone. In thirty-nine pairs of units, where the afferent fibre had a group II conduction velocity, coupling was very efficient and for seventeen pairs the single afferent impulse produced one or more impulses in the s.c.t. cell in at least 90% of trials. The mean number of impulses evoked in s.c.t. cells by a single group II afferent impulse was 1.47. The latencies of the impulses ranged from 1.5 to 14.0 ms, with times to peak and total durations of 2.5-17.5 ms and 4.5-28.0 ms respectively. For two pairs of units where the afferent fibre had a group III conduction velocity the effectiveness of single afferent impulses was much less and the latencies, but not the durations, of the impulses were longer (12 and 17 ms). 3. When the receptive field of the hair follicle afferent fibre was outside, but close to, the firing zone of the s.c.t. neurone there was no indication that single afferent impulses affected the probability of neuronal discharge for thirteen of fifteen pairs of units. Weak excitation was observed in two pairs and this was clear only when two or more afferent impulses were employed. 4. There was a tendency for hair follicle afferent fibres with their receptive fields at or near the centre of the s.c.t. cell's firing zone to be most effective, producing shorter latency responses with more impulses at higher frequencies. When the afferent's field was peripherally located in the s.c.t. neurone's firing zone there was a wide range of responses but these included those with the longest latencies and very few impulses. 5. The results are discussed with reference to previous work on the spinocervical tract and to the known actions of single impulses on other neuronal types. Suggestions are made for the possible excitatory neuronal circuits linking hair follicle afferent fibres to the s.c.t. neurones.
Action Potentials↗
Impulse noise and risk criteria.
Impulse noise causes evidently more severe hearing loss than steady state noise. The additional effect of occupational impulse noise on hearing has been shown to be from 5 to 12 dB at 4 kHz audiometric frequency. Reported cases for compensated for hearing loss are prevalent in occupations where noise is impulsive. For impulse noise two measurement methods have been proposed: the peak level method and energy evaluation method. The applicability of the peak level method is difficult as even the recurrent impulses have different time and frequency characteristics. Various national risk criteria differ from international risk criteria. In France the maximum A-weighted peak level is 135 dB, and in the United Kingdom the C-weighted peak sound pressure is limited to 200 Pa (140 dB). This criterion of unweighted 200 Pa (140 dB) is used in European Union (EU) directive 86/188 and ISO 1999-1990 regardless of the number of impulses. The American Conference of Governmental Industrial Hygienists (ACGIH) has recommended that no exposure in excess of a C-weighted peak sound pressure level of 140 dB should be permitted. At work places these norms do not cause any practical consequences since the impulses seldom exceed 140 dB peak level. In several occupations the impulses are so rapid that they contribute only a minimal amount to the energy content of noise. These impulses can damage the inner ear even though they cause reduced awareness of the hazard of noise. Based to the present knowledge it is evident that there is the inadequacy of the equal energy principle in modelling the risk for hearing loss. The hearing protectors attenuate industrial impulse noise effectively due to the high frequency contents of impulses. Directive regarding the exposure of workers to the risks arising from noise requires that in risk assessment attention should be paid also to impulsive noise. So far there is no valid method to combine steady state and impulse noise. A statistical method for the measurements of industrial impulse noise is needed to get a preferably single number for risk assessment. There is an urgent task to develop risk assessment method and risk criteria for impulsive noise to meet the requirements of the upcoming European Union noise directive.
Adult↗
[Adjustment of dose-response relationship of industrial impulse noise induced high frequency hearing loss with different exchange rate].
OBJECTIVE: To explore a new method to evaluate the dose-response relationship between the noise exposure and prevalence of noise induced high frequency hearing loss. METHODS: Physical examination and questionnaire survey were conducted among 32 mechanical workers, 12 males and 20 females, aged 35.1 +/- 7.2, exposed to industrial impulse noise (impulse noise group), and 163 textile workers, 82 males and 81 females, aged 31.5 +/- 8.7, exposed continuous noise (continuous noise group). SH-126 dosimeter was used to measure the A weighted equal sound level in continuous eight working hours (L(Aeq.8h)) so as to evaluate the individual noise exposure. Cumulative noise exposure (CNE) was calculated with the values of L(Aeq.8h) and noise working year adjusted by different exchange rates (ERs) for each worker. Hearing threshold was measured by audiometer with routine method and adjusted by age and gender according to GBZ49-2002. High frequency hearing loss was diagnosed based on the GBZ49-2002 for each worker. RESULTS: According to the equal energy rule, with the ER = 3 the CNE of the impulse noise group was [103.2 dB (A).year +/- 4.2dB (A).year], significantly lower than that of the continuous noise group [110.6 +/- 6.0 dB (A).year, P < 0.05]. With the ER = 5.5, the CNE of the impulse noise group was 110.3 +/- 6.6 dB (A).year, not significantly different from that of the continuous noise group [110.6 +/- 6.0 dB (A).year]. The high frequency hearing loss prevalence of the impulse noise group was 68.8%, not significantly different that of the continuous noise group (65%, P > 0.05). Trend chi square test showed significant differences in the relationship between CNE and hearing loss prevalence among the impulse noise group with the ER = 3, the impulse noise group with the ER = 5.5, and continuous noise group (all P < 0.01). With the ER = 3, the high frequency hearing loss prevalence of the impulse noise group with the CNE of 100-104 dB (A).year was 76.9%, significant higher than that of the continuous noise group (30.4%, P < 0.05); and the high frequency hearing loss prevalence of the impulse noise group with the CNE of 105-108 dB (A).year was 90.9%, significantly higher than that of the continuous noise group (50.0%, P < 0.05). With the ER = 5.5, there was no difference in the prevalence of high frequency hearing loss between the continuous noise group and impulse noise group. Logistic regression model showed that with the ER = 3, the dose-response curve of the impulse noise group presented a left shift and with a slope sharper than that of the continuous noise group. With the ER increasing the dose-response curve of the impulse noise group showed a right shift and with a gradually lowering slope. When the ER equaled to 6 in the impulse noise group and equaled to 3 in the continuous noise group, the two dose-response curves were almost superposed. CONCLUSION: Impulse noise causes more serious damage in causing high frequency hearing loss than continuous noise according to equal energy rule. Increasing the ER value in the impulse noise group adjusts the dose-response curve to be close to that of the continuous noise group.
Adult↗
Course of multi-impulsive bulimia.
Thirty-two consecutively admitted females with bulimia nervosa (purging type) according to DSM-IV and additional impulsive behaviours (multi-impulsive bulimia (MIB)) and 32 age-matched female controls with DSM-IV bulimia nervosa (purging type) (uni-impulsive bulimia (UIB)) were assessed longitudinally on admission and at discharge following in-patient therapy and at a 2-year follow-up. Multi-impulsive bulimics were defined as presenting at least three of the six of the following impulsive behaviours in their life-time in addition to their bulimic symptoms at admission: (a) suicidal attempts, (b) severe autoaggression, (c) shop lifting (other than food), (d) alcohol abuse, (e) drug abuse, or (f) sexual promiscuity. Multi-impulsive bulimics were more frequently separated or divorced, had less schooling and held less-skilled jobs. Except for interoceptive awareness (EDI), which was more disturbed in multi-impulsive bulimics, there were no differences concerning scales measuring eating disturbances and related areas. Multi-impulsive bulimics showed more general psychopathology--anxiety, depression, anger and hostility, psychoticism--differed in several personality scales from uni-impulsive bulimics (e.g. increased excitability and anger/hostility) and had overall a less favourable course of illness. Multi-impulsive bulimics also received more in- and out-patient therapy previous to the index treatment and during the follow-up period. The data support the notion that 'multi-impulsive bulimia' or 'multi-impulsive disorder' should be classified as a distinct diagnostic group on axis I or that an 'Impulsive Personality Disorder' should be introduced on axis II. The development of more effective treatment for multi-impulsive bulimia is warranted.
Adult↗
A prospective study of the paradoxical relationship between impulsivity and lethality of suicide attempts.
BACKGROUND: Biological studies suggest that lower serotonergic activity is associated with both greater suicide lethality and impulsive personality traits. These results may lead to the conclusion that impulsivity in the attempt should be associated with greater lethality. However, Klerman's review of epidemiologic suicide studies suggests an inverse relationship between impulsivity and lethality. This seemingly paradoxical relationship between impulsivity and lethality has not been explored in large representative clinical samples of suicide attempts. METHOD: During 1996 to 1998, 478 individuals who attempted suicide were studied in a general hospital in Madrid, Spain. Impulsivity was measured as described in the literature by combining 2 items of Beck's Suicidal Intent Scale (active preparation for attempt and degree of premeditation). Lethality of the attempt was assigned 1 of 4 levels according to the need for medical and/or psychiatric treatment. RESULTS: More than half of the attempts were impulsive (55%; 95% confidence interval [CI], 51% to 59%), approximately one fourth of the attempts had an intermediate level of impulsivity (28%; 95% CI, 24% to 32%), and approximately one sixth of the attempts were not impulsive (17%, 95% CI, 13% to 21%). There was an inverse association between the impulsivity and lethality of the suicide attempt (chi2 = 62.639, df = 6, p < .0001). The most impulsive attempts tended to result in less morbidity, while the less impulsive attempts tended to be more lethal. CONCLUSION: If the inverse relationship between impulsivity and lethality is replicated in other large and representative samples, new studies will be needed to clarify the complex interactions between the clinical dimensions (lethality, impulsivity as a state, and impulsivity as a personality trait) and the biological correlates (particularly serotonergic function) of suicidal behavior.
Adult↗
Control of multiple impulse-initiation sites in a leech interneuron.
1. Several heart interneurons (HN cells) of the leech nerve cord have impulse-initiation sites in every segmental ganglion through which their single axons pass. All these initiation sites are capable of producing rhythmic impulse bursts. However, under normal conditions a dominant primary initiation site in the ganglion where the cell body is located suppresses the activity of the other secondary sites. 2. Hyperpolarization of the primary initiation site by injected current permits immediate expression of rhythmic activity by a secondary site, usually the one located in the next posterior ganglion. 3. The free-running impulse burst rhythm of the primary site is stronger than that of the secondary site, having a greater burst duration and a tendency toward a higher burst frequency. 4. Bursts of primary-site impulses intercalated into the secondary-site impulse burst rhythm have a twofold effect. First, early to midway through the secondary-site's burst cycle, they phase delay its impulse burst rhythm. Second, early in the secondary-site's burst cycle, they tend to suppress ongoing impulse bursts, and late in the secondary-site's burst cycle, they tend to suppress the next expected impulse burst. The amount of burst suppression seen early and late in the secondary-site burst cycle depends on the burst duration and intraburst impulse frequency of the intercalated burst. 5. The ability of a train of primary-site impulse bursts to completely suppress secondary-site activity depends on burst duration, intraburst impulse frequency, and burst period. 6. Primary-site impulse trains with burst parameters close to those of naturally occurring primary-site bursts completely suppress secondary-site activity. 7. These results are consistent with the notion that the primary-site impulse burst rhythm of an HN cell suppresses the activity of its secondary site because, cycle by cycle, it delays and/or suppresses the next secondary-site burst so that no secondary-site bursts are produced. Dominance of the primary site over the secondary site is ensured by virtue of the primary-site's stronger impulse burst rhythm.
Animals↗
Increased multiaxial lumbar motion responses during multiple-impulse mechanical force manually assisted spinal manipulation.
BACKGROUND: Spinal manipulation has been found to create demonstrable segmental and intersegmental spinal motions thought to be biomechanically related to its mechanisms. In the case of impulsive-type instrument device comparisons, significant differences in the force-time characteristics and concomitant motion responses of spinal manipulative instruments have been reported, but studies investigating the response to multiple thrusts (multiple impulse trains) have not been conducted. The purpose of this study was to determine multi-axial segmental and intersegmental motion responses of ovine lumbar vertebrae to single impulse and multiple impulse spinal manipulative thrusts (SMTs). METHODS: Fifteen adolescent Merino sheep were examined. Tri-axial accelerometers were attached to intraosseous pins rigidly fixed to the L1 and L2 lumbar spinous processes under fluoroscopic guidance while the animals were anesthetized. A hand-held electromechanical chiropractic adjusting instrument (Impulse) was used to apply single and repeated force impulses (13 total over a 2.5 second time interval) at three different force settings (low, medium, and high) along the posteroanterior axis of the T12 spinous process. Axial (AX), posteroanterior (PA), and medial-lateral (ML) acceleration responses in adjacent segments (L1, L2) were recorded at a rate of 5000 samples per second. Peak-peak segmental accelerations (L1, L2) and intersegmental acceleration transfer (L1-L2) for each axis and each force setting were computed from the acceleration-time recordings. The initial acceleration response for a single thrust and the maximum acceleration response observed during the 12 multiple impulse trains were compared using a paired observations t-test (POTT, alpha = .05). RESULTS: Segmental and intersegmental acceleration responses mirrored the peak force magnitude produced by the Impulse Adjusting Instrument. Accelerations were greatest for AX and PA measurement axes. Compared to the initial impulse acceleration response, subsequent multiple SMT impulses were found to produce significantly greater (3% to 25%, P < 0.005) AX, PA and ML segmental and intersegmental acceleration responses. Increases in segmental motion responses were greatest for the low force setting (18%-26%), followed by the medium (5%-26%) and high (3%-26%) settings. Adjacent segment (L1) motion responses were maximized following the application of several multiple SMT impulses. CONCLUSION: Knowledge of the vertebral motion responses produced by impulse-type, instrument-based adjusting instruments provide biomechanical benchmarks that support the clinical rationale for patient treatment. Our results indicate that impulse-type adjusting instruments that deliver multiple impulse SMTs significantly increase multi-axial spinal motion.
Journal Article↗
Subblocking concentrations of local anesthetics: effects on impulse generation and conduction in single myelinated sciatic nerve axons in frog.
Phenomena seen in axons exposed to subblocking doses serve as the basis for interpreting clinical and behavioral observations during onset and recovery of peripheral nerve block. To delineate the changes in excitability and in impulse conduction caused by subblocking concentrations of local anesthetics (LAs) in myelinated peripheral nerve fibers, LAs were applied to excised frog sciatic nerves while impulse conduction was monitored in single axons. For concentrations ranging from 0.01 to 1.2 times the LA concentration needed to block impulse conduction, three measures of susceptibility to LA were made to quantify the action of the drugs on "resting" fibers (firing rates < or = 0.5 Hz): the increase in the threshold for electrical activation of impulses, the increase in conduction latency reflecting the slowing of impulse conduction in the region exposed to LA, and the "critical blocking concentration" of LA just sufficient to prevent impulse conduction in the recorded fiber. Wide interfiber variation in these variables was observed (e.g., for lidocaine, latency increases at block ranged from 66% to 257% of control, blocking concentrations ranged from 0.29 to 1.40 mM), which was not correlated with fiber diameter (as indicated by resting conduction velocity). Mathematical modeling of impulse conduction in fibers exposed to LA demonstrated that the interfiber variation in susceptibility to LA block could result from interfiber differences in the density of sodium and potassium channels. The effects of LA were also studied in active fibers (firing rates > 0.5 Hz). Local anesthetics reversibly inhibited two normally occurring afteroscillations in membrane threshold related to afterpotentials following an impulse. These were "superexcitability," a transient lowering of threshold lasting as long as 1 s, and "depression," a phase of raised threshold peaking within 2-4 s after an impulse and recovering slowly over several minutes. Impulse activity also transiently increased the apparent potency of LAs. Such "use-dependent" increases in threshold and decreases in conduction velocity showed kinetics that were agent specific, lasting 1 s after a burst of impulses for lidocaine and lasting > 10 s for bupivacaine. At low concentrations, within the range of nontoxic plasma concentrations after systemic administration, the predominant actions of LAs on conducting fibers were transient decreases in excitability and conduction velocity in combination with a reduction of intrinsic oscillatory aftereffects of impulse discharge. These effects may degrade decoding of information in discharge patterns without actually blocking conduction of infrequent impulses, suggesting how functional blockade of coordinated movement and perception may occur even without complete blockade of impulse conduction.
Anesthetics, Local↗
[Study of sensitivity to impulse noise in guinea pig, rat and mouse].
OBJECTIVE: To study sensitivity to impulse noise in guinea pig, rat and mice. METHODS: Six groups were divided. Group I: Guinea pigs (n = 5) were exposed to 50 impulses of 160 dB SPL; Group II: Guinea pigs (n = 5) were exposed to 100 impulses of 160 dB SPL; Group III: Guinea pigs (n = 5) were exposed to 200 impulses of 160 dB SPL; Group IV: Guinea pigs (n = 6) were exposed 400 impulses of 160 dB SPL; Group V: Rats (n = 10) were exposed to 50 impulses of 160 dB SPL; Group VI: Mice (n = 10) were exposed to 50 impulses of 160 dB SPL. ABR thresholds were determined prior to, immediately, one day, one week, two weeks and four weeks after impulse noise exposure. RESULTS: The rat and mice were shown temporary threshold shift (TTS) and permanent threshold shift (PTS) after 50 times impulse noise (160), while no TTS and PTS in the guinea pigs but it was shown TTS and PTS after 400 times impulse noise (160). CONCLUSIONS: Sensitivity to impulse noise is different among guinea pig, rat and mouse. Guinea pig has less sensitivity to impulse noise while rat and mouse have higher sensitivity to impulse noise. In addition, rat has higher sensitivity to impulse noise than mouse.
Animals↗
[Effect of single impulses on cochlear microphone potentials of the guinea-pig cochlea].
The influence of highly intensive single impulses on the cochlea of guinea pig was studied in an acute experiment. Very short impulses of less than or equal to 0.1 ms duration were produced by a sparknoise generator. The cochlear microphonics (CM) to a test stimulus (sinus tone, 3150 Hz) were recorded from the round window and measured prior to, during, and following impulse treatment. During the impulse treatment, the greatest amplitude reduction of CM occurred after the first impulse, while the further impulses caused a decreasing reduction. At first the number of impulses was varied: 1, 3, and 5 impulses were applied at intervals of 15 s each, at an impulse sound level of 164 dB sound pressure level re. 0.002 mubar (SPL). After these impulse treatments, in all cases a continual decrease of CM amplitudes up to a constant end value without recovery was found within a 2-hrs period of observation. The height of the end value depends on the number of impulses applied. Subsequently, at an exposure to 5 impluses the impulse sound level was stepwise reduced (164, 153, 144, 139 and 133 dB SPL). Again, a characteristic decrease of CM amplitudes was observed during the 2-hrs period of observation. The height of the end value is now dependent on the impluse sound level. Impulses of 164, 153 and 144 dB SPL cause a strong decrease of CM while the effect of impulses of 139 and 133 dB SPL is distinctly lower.
Acoustic Stimulation↗