Biomedical subjects

Paul Pauli

Publications and source records attributed to Paul Pauli.

At least 19 recordsLinked to original sources

PubMed2007

Improvement of prefrontal brain function in endogenous psychoses under atypical antipsychotic treatment.

Typical and atypical antipsychotics are thought to exert their effects on different neurotransmitter pathways with specific action of atypical compounds on the prefrontal cortex, but studies directly investigating the effect of those drugs on neurophysiological measures of prefrontal brain function are sparse. We therefore investigated the influence of different antipsychotics on an electrophysiological marker of prefrontal brain function (NoGo anteriorization, NGA) and neuropsychological test scores. For this purpose, 38 patients with endogenous psychoses were investigated at the beginning of a stationary psychiatric treatment and at a 6-week-follow-up. Patients were treated with typical or atypical antipsychotics, or a combination of both. They underwent psychopathological diagnostic and neuropsychological testing, as well as electrophysiological investigations during a Continuous Performance Test. The results indicate that typical and atypical antipsychotics differentially affected the development of the NGA over the course of the treatment, typical antipsychotics tending to result in decreased values at follow-up, and atypical antipsychotics stabilizing, or increasing this parameter. Performance in tests of frontal lobe function generally declined under typical antipsychotics and improved with atypical compounds, changes in Stroop interference correlated with changes in the NGA. We conclude that typical and atypical antipsychotics differ regarding their effect on prefrontal brain function in schizophrenia, atypical neuroleptics often showing a more favorable impact than conventional antipsychotics on respective parameters.

Adult↗

PubMed2006

Musically induced arousal affects pain perception in females but not in males: a psychophysiological examination.

The present study investigated affective and physiological responses to changes of tempo and mode in classical music and their effects on heat pain perception. Thirty-eight healthy non-musicians (17 female) listened to sequences of 24 music stimuli which were variations of 4 pieces of classical music. Tempo (46, 60, and 95 beats/min) and mode (major and minor) were manipulated digitally, all other musical elements were held constant. Participants rated valence, arousal, happiness and sadness of the musical stimuli as well as the intensity and the unpleasantness of heat pain stimuli which were applied during music listening. Heart rate, respiratory rate and end-tidal PCO(2) were recorded. Pain ratings were highest for the fastest tempo. Also, participants' arousal ratings, their respiratory rate and heart rate were accelerated by the fastest tempo. The modulation of pain perception by the tempo of music seems to be mediated by the listener's arousal.

Adolescent↗

PubMed2006

The factor structure and reliability of the Illness Attitude Scales in a student and a patient sample.

BACKGROUND: The Illness Attitude Scales (IAS), designed by Kellner in 1986, assesses fears, beliefs, and attitudes associated with hypochondriasis and abnormal illness behaviour. However, its factor structure is, especially for translations of the IAS, not sufficiently explored. Thus, the present Study aimed to analyse the factor structure of the IAS in a German student and a patient population using exploratory factor analysis. METHODS: A mixed student (N = 296) and a mixed patient (N = 130) sample completed the IAS. The data was submitted to principal components analyses (PCA) with subsequent oblique rotations. From identified factor structures, scales were derived and submitted to reliability analyses as well as to a preliminary validity analysis. RESULTS: The PCA revealed a four-factor solution in the student sample: (1) fear of illness and death; (2) treatment experience; (3) hypochondriacal beliefs; and (4) effect of symptoms. In the patient sample, the data was best explained by a two-factor solution: (1) health related anxiety and (2) effect of symptoms and treatment experience. All scales reached good to acceptable reliability coefficients. The scales derived from the student sample and those derived from the patient sample were able to distinguish between pain patients and a matched group of normal controls. CONCLUSION: Our data suggests that the IAS is in student samples best represented by a four factor-solution and in patient samples by a two-factor-solution.

Adult↗

PubMed2006

Additive effects of serotonin transporter and tryptophan hydroxylase-2 gene variation on emotional processing.

Prior studies reported that functional variants of both the serotonin transporter (5-HTT) and tryptophan hydroxylase-2 genes (TPH2), 2 key regulators of the serotonergic signaling pathway, modulate amygdala activation during emotional processing. We addressed the question whether these 2 gene variants modulate each other, using an emotional picture-processing task. Specifically, we measured event-related potentials (ERPs) during a passive emotional picture perception task, focusing on ERPs for the early posterior negativity (EPN) around 240 ms and for the slow wave starting at 315 ms. We found evidence for increased neural activity at 240 ms in individuals who carried 1 or 2 copies of the low-expression short variant of the 5-HTT. Carriers of T variant of the TPH2 also showed a tendency toward increased neural activity at 240 ms. Moreover, we observed an additive effect of both genotypes for EPN, with highest neural activity to emotional stimuli in individuals carrying combination of both short variant of 5-HTT and T variant of TPH2. Our results indicate that both the 5-HTT and the TPH2 genotypes modulate the sensory encoding of affective stimuli during early steps of visual processing and reveal additive effects of 2 genes in the serotonergic control of emotion regulation.

Adult↗

PubMed2006

Is emotion processing affected by advancing age? An event-related brain potential study.

The recognition of emotions is presumably affected by advancing age, which is known from subjective reports and recognition tasks. To differentiate perception from executive function more clearly, the discrimination of emotions was investigated with event-related brain potentials (ERPs) from 21 electrodes in 14 elderly (ages 59-74) and 13 younger participants (ages 30-40) triggered by a rapid (3 Hz) serial visual presentation (RSVP) of high and low arousing pictures. Additionally, affective ratings of valence and arousal of a representative sample of 54 pictures were obtained. An early posterior negativity (EPN) as an index of early emotion discrimination was analyzed in an early (168-232 ms) and a late (232-296 ms) time window. Both groups showed an EPN associated with pictures of high emotional arousal. However, the EPN was slightly delayed in elderly participants. Thus, the affective modulation of the EPN was reduced in elderly subjects in the early time window, but not in the late time window. Ratings of valence or arousal did not differ between groups. In sum, these results point towards an age-related delay of early visual emotion discrimination. However, this delay seems not to influence further evaluative processing of emotional stimuli.

Adult↗

PubMed2006

Phylo- and ontogenetic fears and the expectation of danger: differences between spider- and flight-phobic subjects in cognitive and physiological responses to disorder-specific stimuli.

To compare specific phobias with an assumed phylogenetic or ontogenetic origin in responses to fear-relevant (FR) stimuli, 17 spider- and 17 flight-phobic participants were exposed to pictures of spiders, flight accidents, or mushrooms randomly followed by either a startling noise or nothing else. While both groups showed a disorder-specific expectancy bias, only spider-phobic participants exhibited a disorder-specific covariation bias. Spider-phobic participants also showed enhanced skin conductance responses (SCRs), event-related brain potentials (ERPs), and startle responses triggered by disorder-specific FR pictures while flight-phobic participants showed only disorder-specific enhanced SCRs. In sum, our direct comparison between ontogenetic and phylogenetic phobias revealed that the former is characterized by biased and enhanced responses triggered by disorder-specific FR stimuli presumably based on a biological preparedness.

Adult↗

PubMed2006

How to choose a seat in theatres: always sit on the right side?

Right seat-side preference in a cinema has been explained by suggesting that it allows for emotional information processing by the right hemisphere (Karev, 2000). In order to determine seat-side preferences, participants in our experiments had to choose seats on cinema, theatre, and restaurant maps. The maps varied with respect to cinema screen, theatre stage, and restaurant entrance positions as viewed by the participants: on top, to the right, to the left, and at the bottom. Seat-side preference was found to be modified by the map's arrangement: With screen, stage, or entrance on top, participants preferred seats to the right of the screen, stage, or entrance, while for the other positions the results were not conclusive. Based on these results it cannot be concluded that the preference for a cinema seat is solely mediated by the preparation for an upcoming event to optimise emotional processing by the right hemisphere. Rather, seat choice seems to be determined by basic behavioural tendencies, such as which side to turn to when entering a room, or by visual attentional orientation.

Adolescent↗

PubMed2006

Electromyographic responses to static and dynamic avatar emotional facial expressions.

Facial muscular reactions to avatars' static (neutral, happy, angry) and dynamic (morphs developing from neutral to happy or angry) facial expressions, presented for 1 s each, were investigated in 48 participants. Dynamic expressions led to better recognition rates and higher intensity and realism ratings. Angry expressions were rated as more intense than happy expressions. EMG recordings indicated emotion-specific reactions to happy avatars as reflected in increased M. zygomaticus major and decreased M. corrugator supercilii tension, with stronger reactions to dynamic as compared to static expressions. Although rated as more intense, angry expressions elicited no significant M. corrugator supercilii activation. We conclude that facial reactions to angry and to happy facial expressions hold different functions in social interactions. Further research should vary dynamics in different ways and also include additional emotional expressions.

Adult↗

PubMed2005

Emotion processing in Parkinson's disease: dissociation between early neuronal processing and explicit ratings.

OBJECTIVE: Patients suffering from Parkinson's disease (PD) have a diminished ability to discriminate facial expressions of emotion. We investigated early emotion discrimination deficits in PD by means of event-related potentials (ERPs). METHODS: Emotional pictures were presented to 14 PD patients and 14 healthy controls in a rapid serial visual presentation paradigm (three frames per second) while EEG was recorded. In addition, valence and arousal ratings were obtained for a representative subsample of 54 pictures. RESULTS: PD patients rated pictures of highly arousing content as less exciting than did healthy controls. Pictures of high compared to low emotional arousal were associated with a pronounced relative negative shift in the ERP waveform over parietal and occipital sites developing about 220 ms after picture onset. This early posterior negativity (EPN) did not differ between PD and control group. CONCLUSIONS: This dissociation of affective ratings and early ERP components supports the view that PD is associated with blunted emotional responses, but there is no evidence for a deteriorated early visual processing of emotional stimuli. SIGNIFICANCE: Frequently reported deficits in emotion discrimination are likely not due to deficits in early emotion processing.

Aged↗

PubMed2005

Brain processes associated with target finding.

The response execution stage of cognitive skill consists of several substages, including finding the proper response location among available alternatives and moving the effector to the target location. In order to unravel the brain dynamics associated with the finding process, the present experiments used two experimental conditions. In the number condition, which requires both finding and moving, subjects are presented on each trial with a digit, 0-9, are required to find that digit on a circular clock face, and then to move a cursor to that target's location. In the arrow condition, an arrow pointing to the location of the target on the clock face circumference appears simultaneously with the target digit; no target finding is required because subjects need only to move the cursor along the path marked by the arrow. A pilot and the main experiment revealed that response initiation times but not movement times were affected by these experimental manipulations. Analysis of magnetoencephalographic (MEG) activity revealed an early occipital activity which was not affected by experimental manipulations. Later activity with central-parietal and parieto-temporal loci presumably reflected changes in the dorsal and ventral pathways, respectively, and these were affected by experimental conditions. Finally, finding processes seem to be associated with a second late activation of the ventral pathway presumably reflecting ongoing recognition processes.

Adolescent↗

PubMed2005

Electrocortical evidence for an early abnormal processing of panic-related words in panic disorder patients.

Panic patients are hypothesized to have particularly elaborated cortical networks for panic-related stimuli, and this characteristic should be associated with an abnormal automatic processing of these stimuli. Panic-related and neutral words were presented to 25 panic patients and 25 matched healthy controls either at individually determined perception thresholds (threshold condition) or for 1000 ms (above threshold condition). Word recognition for words presented at perception threshold (threshold words), and event-related brain potentials (ERPs) triggered by threshold and above threshold words were analyzed. In the threshold condition, both panic patients and control participants correctly recognized more panic-related than neutral words. An additional analysis restricted to participants who used an intuitive strategy for word identification revealed an enhanced frequency of correctly identified panic-related words in panic patients. In the ERPs, only panic patients exhibited enhanced positive potentials during early time windows (200-400 ms after stimulus presentation) triggered by panic-related compared to neutral threshold words. In late (400-600 ms) and very late (600-1000 ms) time windows, both groups showed a greater ERP positivity for panic-related than for neutral words. These data suggest that panic patients are characterized by an early automatic and elaborated processing of disorder-relevant stimuli.

Adult↗

PubMed2005

Selective processing of pain-related word stimuli in subclinical depression as indicated by event-related brain potentials.

An intense discussion still exists as to whether pain and depression are causally related or independent of each other. To investigate processing of pain-related word stimuli in subclinically depressed individuals, we designed an event-related potentials study in a group control design. Pain words and neutral words were presented to 16 subclinically depressed and 16 control participants. Behavioral and electrophysiological measures were taken during lexical decision and recognition tasks. Depressive compared to control participants showed enhanced P300 amplitudes at parietal electrodes triggered by pain-related words during the lexical decision task, which presumably is a sign of enhanced recollection processes for these word stimuli. In line with these electrophysiological findings, depressed participants also tended to better recall the pain-related words in the later recognition task than control participants. We conclude that subclinically depressed individuals selectively process pain-related stimuli, and this processing bias could enhance their vulnerability to develop pain symptoms.

Adult↗

PubMed2005

Altered processing of pain-related information in patients with fibromyalgia.

Pressure pain thresholds (PPTs) and event-related potentials (ERPs) elicited by emotional words were analyzed in 12 patients with fibromyalgia (FM) and 12 matched healthy subjects. PPTs were assessed at the middle finger of both hands, before and after the experiment. Overall, FM patients and healthy subjects did not differ in PPT. Nevertheless, FM patients as compared with healthy controls were characterized by a significant enhancement of pain sensitivity from the beginning to the end of the experiment indicating a long lasting sensitization due to repeated stimulation. ERPs were recorded during a language decision task where subjects had to react to unpleasant pain-related and emotionally neutral words depending on syntactic or orthographic cues. An emotional category effect was observed on N400 and P300 components of the ERP, indicating that unpleasant words elicited more positive amplitudes than neutral words. A significant group effect was observed on P200 amplitudes, showing reduced amplitudes in FM patients as compared to healthy controls. Furthermore, unpleasant pain-related compared to neutral words triggered significantly enhanced late positive slow waves in healthy controls, while a comparable effect was not found in FM patients. The ERP and PPT data suggest that FM patients are characterized by an altered cognitive processing of pain-related information and by an abnormal adaptation to mechanical pain stimuli, respectively.

Adult↗

PubMed2005

Binocular rivalry between emotional and neutral stimuli: a validation using fear conditioning and EEG.

When two incompatible pictures are projected to the two eyes, they compete for perceptual dominance. Previous research has claimed that meaningful and emotionally valenced pictures predominate over neutral pictures in this rivalry. This may be interpreted as evidence for preferential processing of emotionally significant stimuli in the visual system but it is difficult to dismiss that the physical characteristics of the different pictures or response biases influenced the results of these studies. Thus, we set out to examine the influence of emotion using methods eliminating the influence of physical characteristics and minimizing response biases. We used simple visual patterns and induced emotional valence by fear conditioning. In Experiment 1 the aversive CS+ predominated over the CS-. In Experiment 2 we extended previous findings by showing that participants' self-reported perception is validated by corresponding steady-state visually evoked potentials in the EEG in the context of such a conditioning experiment. This was accomplished by frequency coding the rivalling stimuli with a stimulus specific pattern reversal and extracting the corresponding frequency from the occipital lobe EEG. Taken together, these studies provide further evidence that picture valence can influence perception in binocular rivalry. This is discussed in terms of subcortical mechanisms supporting the efficient processing of threatening information.

Adult↗

PubMed2005

Covariation bias and its physiological correlates in panic disorder patients.

A covariation bias, i.e., the overestimation of random contingencies between fear-relevant stimuli and aversive consequences, seems to characterize anxiety disorders. Panic patients (n=30) and healthy controls (n=25) were exposed to panic-relevant, neutral, and phobia-relevant but panic-irrelevant picture stimuli, followed randomly be aversive consequences (acoustic startle stimuli). While covariation estimates reflected objective contingencies in both groups, only panic patients revealed a more negative Contingent Negative Variation (CNV) to panic-relevant than to phobia-relevant and neutral pictures. For startle reflex, only main effects of picture category were found, indicating that valence effects of picture stimuli were not specifically distorted in panic patients. CNV presumably reflects a biased processing of disorder-relevant stimuli by panic patients, perhaps with the expectation that aversive consequences will follow these stimuli.

Acoustic Stimulation↗

PubMed2005

Implicit and explicit memory processes in panic patients as reflected in behavioral and electrophysiological measures.

Implicit and explicit memory processes for panic-relevant and neutral word stimuli were examined in 16 panic patients and 16 healthy participants matched for sex, age, and education, using behavioral and electrophysiological measures. In the study phase, panic-relevant and neutral words were presented and the level of processing was varied by requiring either shallow (orthographic) or deeper (syntactic) processing. Implicit memory was tested with a lexical decision task, explicit memory with a recognition task. Panic patients and healthy participants did not differ in behavioral (response time) or event-related brain potential (ERP) measures of implicit memory. However, panic patients deviated from healthy participants in the recognition test, an explicit memory test. Although recognition of panic words was overall worse compared to neutral words, panic patients compared to healthy participants exhibited enhanced discrimination scores and faster reaction times for panic words. The level of processing manipulation had comparable effects on patients and healthy participants. While neither behavioral nor electrophysiological measures provided evidence for an implicit memory bias in panic patients, behavioral measures confirmed an explicit memory bias in panic patients for panic-relevant stimuli.

Adult↗

PubMed2005

Abstract stimuli associated with threat through conditioning cannot be detected preattentively.

Studies of anxiety suggest that threat stimuli can be identified preattentively, but this conclusion is questionable because of possible low-level perceptual confounds. Two experiments used visual search tasks in which abstract shapes were conditioned to carry neutral or negative valence. Experiment 1 found generally faster responses to threat-associated abstract stimuli but no evidence that they were detected preattentively, irrespective of trait anxiety level. A similar pattern was found in Experiment 2, in which individuals high in snake or spider fear showed no evidence of preattentive detection of abstract stimuli associated with their feared object. In contrast, implicit behavioral measures showed significant effects of conditioning, demonstrating that targets associated with threat were negatively evaluated in these experiments.

Adult↗

PubMed2005

Affective modulation of brain potentials to painful and nonpainful stimuli.

In accordance with the emotional priming hypothesis, emotions seem to modulate pain perception and pain tolerance thresholds. To further evaluate this association, event-related brain potentials (ERPs) elicited by painful and nonpainful electrical stimuli during processing of positive, neutral, and negative valenced pictures were recorded from 30 healthy volunteers. Valence of pictures affected pain ratings and the N150 elicited by painful stimuli, with lowest amplitudes for positive pictures and highest amplitudes for negative pictures. The P260 elicited by painful and nonpainful stimuli was modulated by arousal with reduced amplitudes with arousing (positive or negative) compared to neutral pictures. N150 amplitudes varying with picture valence seem to reflect an affective modulation of pain perception whereas P260 amplitudes varying with picture arousal rather reflect non-pain-specific attentional processes.

Adolescent↗