Heart rate and visual evoked potentials during figuring arithmetic problems in boys acquired in early childhood with minimal brain damage

Changes of the pattern reversal EP and heart rate (HR) during calculating were studied on 32 boys with minimal brain damage and a control group (n 27) matched in age, sex and intelligence. The introduction of a reference period and repetition of the calculation period should improve the value of all results and should give simultaneously a first insight in the course of the parameters investigated, during mental loading. Both groups reached the same results in calculating, yet only the brain damaged boys simultaneously showed significant longer latencies of the EP. This result was interpreted as an effect of the higher loading of the damaged subjects. The task-depended increase of the HR was significant in both groups. The HR-level was getting lower with the increasing number of brain damage criteria. The results of intercorrelation between in physiologic parameters and datas of subjective feeling and results of calculating was negative in all cases. These findings were interpreted on the basis of several difficulties to find out clear cut patterns of reaction for different clinical groups.     

Response of the pituitary-adrenal axis in terms of type a behaviour,hostility and vital exhaustion in healthy middle-aged men

Abstract

Pituitary-adrenal axis was studied in terms of Type A behaviour, hostility and vital exhaustion among 69 healthy middle-aged men. The results showed that psychological factors could explain a significant proportion of the biologically manipulated responses of HPA axis, but they worked in different ways. Type A behaviour was related to a high level of mean basal ACTH and a low level of cortisol response to ACTH stimulation after dexamethasone suppression; hostility was related to a high level of mean basal cortisol and a high cortisol in cortisol/ACTH ratio, while vital exhaustion was characterized by a low level of mean basal ACTH and a decreased ACTH in relation to cortisol. The adrenocortical patterns, i.e. a high ACTH-low cortisol; a high cortisol; and a low ACTH-low mean basal cortisol, as related to Type A behaviour, hostility and exhaustion, respectively, are in line with the traditional physiological stress model and suggest that different adrenocortical responses might be able to identify different mental stress processes. Sense of control has been suggested to be a key concept for psychological understanding of this finding.     

Practice and some methodological problems in unidimensional information transmission

Fifty circular lights differir.g in diameter from 4 to 53 cm and increasing by 1 cm were presented 135 times each to five Ss who were asked to identify each circle. Presentations were in random order. Indices of information transmission (T), response equivocation H S(R), and response uncertainty H(R) were calculated for different phases of the experiment for individual and pooled (across Ss) responses. Results have shown systematic rising of transmission and lowering of H S(R), while H(R) remained almost constant. All transmission indices calculated from pooled responses were systematically lower than comparable indices calculated from individual responses. Individual and pooled T values calculated from all responses given during the experiment were not representative for the level of identification performance at the end of the experiment. Conclusions were reached that (1) channel capacity indices should not be calculated from all individual responses given during the experiment or from pooled responses of different Ss, and (2) indices of channel capacity should be calculated only after the performance of Ss has reached a final and stable level, which means after enough repetitions of each stimulus.     

The effects of incorrect pain expectations on acquired fear and pain responses

Previous experimental research on the effects of incorrect intensity expectations of aversive events can be criticized because intensity expectations were not manipulated independently from changes in objective intensity. The present study aims at investigating the effects of incorrect intensity expectations on the immediate and later responses to a painful stimulus, and on the acquisition of anticipatory responses, with proper experimental control. Subjects (n = 62) received 20 painful stimuli of varying intensity. In the control group intensities were correctly signalled on all trials by an analogue signal. On 3 trials the signal was too large in the overprediction condition, and too small in the underestimation condition. Underpredicted painful experiences were related to subsequent higher pain responses on the physiological level, but not on the subjective level; and to increased anticipatory responses (increased pain expectations, uncertainty, subjective fear, skin conductance responses). Skin conductance level also indicated increased fear after underpredicted experiences. Overpredicted painful experiences were related to a faster decrease in subjective fear compared to the control group, but did not influence other variables. The findings support the notion that underpredictions contribute to the acquistion of fear and disrupt habituation processes. The asymmetrical processing of the two kinds of incorrectly predicted experiences is discussed.     

Terrorists and Democrats: Individual Reactions to International Attacks

Three experiments conducted in 1997 and 1998 explored individual responses to reported fictitious international conflict involving the United States and other nations. Participants escalated the conflictual level of their responses to repeated attacks. In Experiment 1, escalation of conflict was greater in response to terrorist attacks than to military ones. In Experiment 2, after the initial attacks, men were more conflictual in responding to terrorist attacks by a democratic nation than by a nondemocratic nation, whereas the opposite pattern was found for women. In Experiment 3, participants responded with a higher level of conflict to terrorist attacks on military targets than to attacks on cultural/educational targets. Participants with greater personality dominance showed steeper escalation of conflict in their responses across successive attacks. These results are interpreted within the framework of an image theory of international relations and an expansion of the democratic peace hypothesis.     

Behavioral conditioned responses across multiple conditioning/testing trials elicited by lithium- and amphetamine-paired flavors

The present experiment measured the pattern of conditioned responses across 10 conditioning/testing trials which were elicited by an intraoral presentation of either a lithium- or an amphetamine-paired flavor. A nonspecific conditioned response pattern of suppressed limb flicking after five conditioning trials and of suppressed scratching after six conditioning trials was supported by both drugs. Lithium-specific increased activity level after one conditioning trial and chin rubbing after two conditioning trials were observed across conditioning/testing days. The lithium-specific conditioned responses were not the result of a stronger flavor aversion, because both lithium and amphetamine produced equivalent flavor avoidance responses across the 10 conditioning/testing trials. The results support previous research which suggests that flavor aversions produced by lithium and amphetamine are produced by different unconditioned response mechanisms.     

Improvement of mental imagery after prism exposure in neglect: a case study

Previous work has shown that various symptoms of unilateral neglect, including the pathological shift of the subjective midline to the right, may be improved by a short adaptation period to a prismatic shift of the visual field to the right. We report here the improvement of imagined neglect after prism exposure in a patient with a left unilateral neglect. Despite a strong neglect observed for mental images as well as for conventional tests, the mental evocation of left-sided information from an internal image of the map of France map was fully recovered following prism adaptation to the right. This improvement could not be explained by the alteration of visuomotor responses induced by the prism adaptation. Prism adaptation may therefore act not only on sensory-motor levels but also on a higher cognitive level of mental space representation and/or exploration.     

Psychophysiological responses to cooperation: The role of outcome and gender

Instances of sustained cooperative behaviour in humans can be considered as an adaptive strategy that enhances the probability of reaching a goal. This study investigates psychophysiological responses to cooperation in healthy subjects, while considering outcome and gender as potential moderators of these responses. Salivary cortisol levels (Csal), heart rate (HR), skin conductance level (SCL), nonspecific skin conductance responses (NSRs), and mood states were measured at different points before, during and after a Lego house‐building task in undergraduate men (n = 22) and women (n = 20). Once the task was finished, the experimenter informed the participants about the outcome obtained (positive or negative). Cooperation produces an increase in HR, SCL, and NSR responses. When the outcome is positive it produces a gradual diminution in Csal levels, but when the outcome is negative there is a significant increase in Csal levels after the task followed by a progressive decrease. Men with positive outcomes showed a lower area under curve (AUC) in Csal than women with a negative outcome. Men had more NSR responses in all periods other than the rest period. Several mood states are differently affected by the combined effect of outcome and gender. Our laboratory results can be generalized to other situations in which negotiation, mediation, and cooperative strategies are relevant for taking decisions and/or solving problems.     

刺激同一性对错误后反应的影响

当错误发生后,人们往往会放慢错误后反应的速度,以避免错误的再次发生,许多研究者认为,这是自上而下的认知控制对错误后反应的影响.为了探讨刺激属性是否也在错误后的反应中起作用,本研究从刺激同一性角度出发,探讨错误反应刺激与错误后刺激的同一性以及反应-刺激间隔时间(RSI)对错误后反应的影响.结果发现,当错误后的刺激与错误反应的刺激一致时,可减小错误后反应时延长的程度,同时,RSI越大,PES越小.本研究得出结论,刺激同一性和RSI作为自下而上的刺激驱动在PES的产生过程中发挥了作用.     

Neural representation of consciously imperceptible speech sound differences

The concept of subliminal perception has been a subject of interest and controversy for decades. Of interest in the present investigation was whether a neurophysiologic index of stimulus change could be elicited to speech sound contrasts that were consciously indiscriminable. The stimuli were chosen on the basis of each individual subject's discrimination threshold. The speech stimuli (which varied along an F3 onset frequency continuum from /da/ to /ga/) were synthesized so that the acoustical properties of the stimuli could be tightly controlled. Subthreshold and suprathreshold stimuli were chosen on the basis of behavioral ability demonstrated during psychophysical testing. A significant neural representation of stimulus change, reflected by the mismatch negativity response, was obtained in all but 1 subject in response to subthreshold stimuli. Grand average responses differed significantly from responses obtained in a control condition consisting of physiologic responses elicited by physically identical stimuli. Furthermore, responses to suprathreshold stimuli (close to threshold) did not differ significantly from subthreshold responses with respect to latency, amplitude, or area. These results suggest that neural representation of consciously imperceptible stimulus differences occurs and that this representation occurs at a preattentive level.     

The Influence of an Acute Bout of Whole Body Vibration on Human Postural Control Responses

The use of vibrating platforms has become increasingly available, and popular at sports and rehabilitation institutes. Given the discrepancies in the literature regarding whole body vibration (WBV) and human reflexive responses, the purpose of this study was to examine the acute effects of WBV on postural response latencies, as well as associated electromyography measures of the lower extremities during balance perturbations. Reflexive responses during backward and forward balance perturbations were examined before, after, and 10 min after a bout of WBV. The findings suggest that following an acute bout of whole body vibration, muscle activity of the lower extremities is decreased during a reflexive response to an unexpected perturbation, and may be associated with faster reaction time.     

Modeling panel detection frequencies by queuing system theory: an application in gas chromatography olfactometry

In continuous vigilance tasks, the number of coincident panel responses to stimuli provides an index of stimulus detectability. To determine whether this number is due to chance, panel noise levels have been approximated by the maximum coincidence level obtained in stimulus-free conditions. This study proposes an alternative method by which to assess noise levels, derived from queuing system theory (QST). Instead of critical coincidence levels, QST modeling estimates the duration of coinciding responses in the absence of stimuli. The proposed method has the advantage over previous approaches that it yields more reliable noise estimates and allows for statistical testing. The method was applied in an olfactory detection experiment using 16 panelists in stimulus-present and stimulus-free conditions. We propose that QST may be used as an alternative to signal detection theory for analyzing data from continuous vigilance tasks.     

Alexithymia is associated with an augmenter profile, but not only: Evidence for anticipation to arousing music

Grynberg, D., Davydov, D. M., Vermeulen, N. & Luminet, O. (2012). Alexithymia is associated with an augmenter profile, but not only: Evidence for anticipation to arousing music. Scandinavian Journal of Psychology 53, 375-381. It has been suggested that high alexithymia scorers have an 'augmenter' profile which amplifies their physiological and subjective responses to highly arousing stimuli. The aim of this study was to test this theory using several physiological measures. Participants listened to musical excerpts either in a 'weak-to-strong' or a 'strong-to-weak' order of arousing levels of stimuli. The results show that alexithymia was associated with an augmenter profile for subjective reports for the most arousing stimulus and with stronger skin conductance level responses in the 'strong-to-weak' order. These results partially support the augmenter profile and reveal that alexithymia may be associated with higher anticipation for the most arousing excerpt.     

Forgetting in recognition memory with and without recollective experience

Retention interval was manipulated in two recognition-memory experiments in which subjects indicated when recognizing a word whether its recognition was accompanied by some recollective experience ("remember") or whether it was recognized on the basis of familiarity without any recollective experience ("know"). Experiment 1 showed that between 10 min and 1 week, "remember" responses declined sharply from an initially higher level, whereas "know" responses remained relatively unchanged. Experiment 2 showed that between 1 week and 6 months, both kinds of responses declined at a similar, gradual rate and that despite quite low levels of performance after 6 months, both kinds of responses still gave rise to accurate discrimination between target words and lures. These findings are discussed in relationship to current ideas about multiple memory systems and processing accounts of explicit and implicit measures of retention.     

Prejudice as Self‐Control Failure1

Research has suggested that whereas stereotypical attitudes may be automatically activated, the response to these stereotypes can be controlled. Anything that interferes with self‐control may result in more biased behavior. The ego strength model hypothesizes that after exerting self‐control, subsequent self‐control performance will suffer. Hence, depletion of ego strength may lead to increased prejudice. In 2 studies, depletion was found only to affect individuals who normally try to control their prejudicial responses. Participants who do not normally try to control their use of stereotypes were equally prejudiced, regardless of their level of ego strength. The results have implications for prejudice and stereotyping, as well as models of self‐control.     

Operant responding in Siamese fighting fish (Betta splendens) as a function of schedule of reinforcement and visual reinforcers

Siamese fighting fish were trained to emit an operant response that was reinforced by the opportunity to view a motion picture film image of another fish. Performance under various schedules of reinforcement was examined. When reinforcement followed every response and when reinforcement was delivered after every second response, the number of responses per session was higher than during operant level or during extinction. Reinforcement delivered following intervals of no responding (differential reinforcement of other behavior) markedly decreased responding. Light from a projector without film was found to be as effective a reinforcer as film reinforcement. Responding when projector light reinforcement followed every response was maintained at approximately the same level as that obtained under film reinforcement. Responses per session decreased when only the light was delivered on a differential-reinforcement-of-other-behavior schedule. The behavior of the fish during presentation of the film was markedly different from their behavior while the projector light was being presented.     

Reinforcement contingencies and signal detection.

Pigeons were trained to discriminate temporal stimuli in a discrete-trial signal-detection procedure. Pecks to one side key were reinforced intermittently after exposure to one duration, and pecks to the other side key were reinforced intermittently after exposure to a different duration. In Experiment I, the allocation of reinforcers was varied systematically for correct responses and for errors, using a procedure that controlled the obtained numbers of reinforcers. When reinforcers were allocated symmetrically, the level of discrimination decreased as the proportion of reinforcers for errors increased. When reinforcers were allocated asymmetrically, the decrease in discrimination was less systematic. Bias toward one or the other side key roughly matched the ratio of reinforcers obtained by pecks at those keys, independent of the level of discrimination. In Experiment II, the overall rate of reinforcement for correct responses was varied both within and between experimental conditions. The level of discrimination was positively related to the overall rate of reinforcement. The discrimination data of both experiments were interpreted in relation to the contingencies of reinforcement and nonreinforcement, characterized by the average difference in reinforcement probability for correct responses and errors.     

Note on aftereffect of unidirectional sound-level change with different durations of test stimulus

Prolonged listening to unidirectional change of sound level in a tone can cause a steady tone afterwards to change in apparent loudness in the opposite direction. Subjectively the present aftereffect appears strong immediately after removal of the adaptor, becoming much weaker within a second or so. To confirm this, the aftereffect was measured by nulling with different durations of test stimulus changing steadily in sound level. As predicted, rate of change of sound level was greater for the shorter test stimuli. This suggests that aftereffect measurement by nulling may be best achieved with short test stimuli. However, responses to shorter test stimuli were generally more scattered.     

Dissociating object-based and space-based affordances

In what we term the orientation effect, faster spatial responses are made to the corresponding task irrelevant orientation of an object. We ask how this effect relates to object affordances, how attention may be involved, and how the effect relates to the better understood Simon effect. Two separate stimulus-response compatibility effects (an orientation effect and a Simon effect) were observed when spatial responses were made to photographs of objects whose orientation and location had been simultaneously manipulated. When attentional demands were high these separate effects were found using hand responses and foot responses, suggesting an abstract rather than specific coding of object affordances. However, when attentional demands were low only the Simon effect was observed, suggesting that, in order to obtain the orientation effect, objects must be represented at the level of an object.     

Effects of ratio reinforcement schedules on discrimination performance by Japanese monkeys

In Experiment 1, Japanese monkeys were trained on three conditional position-discrimination problems with colors as the conditional cues. Within each session, each problem was presented for two blocks of ten reinforcements; correct responses were reinforced under continuous-reinforcement, fixed-ratio 5, and variable-ratio 5 schedules, each assigned to one of the three problems. The assignment of schedules to problems was rotated a total of three times (15 sessions per assignment) after 30 sessions of acquisition training. Accuracy of discrimination increased to a moderate level with fewer trials under CRF than under ratio schedules. In contrast, the two ratio schedules, fixed and variable, were more effective in maintaining accurate discrimination than was CRF. With further training, as asymptotes were reached, accuracy was less affected by the schedule differences. These results demonstrated an interaction between the effects of reinforcement schedules and the level of acquisition. In Experiment 2, ratio sizes were gradually increased to 30. Discrimination accuracy was maintained until the ratio reached 20; ratio 30 strained the performance. Under FR conditions, accuracy increased as correct choice responses cumulated after reinforcement.