Diese Arbeit wurde durch einen Zuschuss von der Swiss National Science Foundation (: PBEZP3-131154 CE) unterstützt

1. Betreff Recruitment <ol><li> Themen werden über ein Online-Datenbank 5, die eine Liste von etwa 3000 freiwillige Studenten rekrutiert. Aus dieser Liste haben wir nur Kontakt Frauen, die bisher nicht in ähnlichen Studien teilgenommen und fragen sie, ob sie Interesse an einer Teilnahme an dieser Studie sind. Wir laden ausschließlich Frauen als den zeitlichen Verlauf der neurophysiologischen Wirkungen nach akuter Testosteron Verwaltung ist auch bei den Frauen 6,7 etabliert. Für Männer ist diese Zeit natürlich noch nicht sehr gut verstanden. </li><li> Die interessierten Personen werden dann in einem Telefon-Interview gesiebt, um die eingenommenen Medikamente, somatische Krankheiten, hormonelle Kontrazeption oder neurologischen oder psychiatrischen Erkrankungen auszuschließen. </li><li> Da endogenen Sexualhormone zu niedrig und stabil in der ersten Hälfte des weiblichen Zyklus neigen wir führen ein zweites Telefon-Interview, um Informationen über die Stabilität und die Dauer des Zyklus zu gewinnen. Themen werden dann gebeten, das Experiment innerhalb von 10 Tagen kommen aus der Anfang ihres Menstruationszyklus. Sie sind ferner angewiesen, vom Alkohol oder Koffein und Rauchen für 24 Stunden verzichten, bevor das Experiment. </li><li> Themen werden in Gruppen von einer durchschnittlichen Größe von 12 bis Versuchslabor des Instituts für Empirische Wirtschaftsforschung eingeladen, in Zürich, Schweiz. </li></ol> 2. Versuchsdurchführung <ol><li> Alle Sitzungen beginnen um 01.00 Uhr für die zirkadiane Variation in Steroidhormon zu kontrollieren. </li><li> Wir führen einen Schwangerschaftstest vor Beginn des Experiments, um eine Schwangerschaft auszuschließen. </li><li> In Vorbereitung des Experiments, das Testosteron und optisch nicht zu unterscheiden Placebo-Pillen werden nach dem Zufallsprinzip zu zwölf Workstations markiert 11.59 im Laborraum durch eine Person, die nicht in das Experiment sonst beteiligt ist verteilt. </li><li> Am Eingang zum Labor zieht jeder der zwölf unterliegen einer Karte mit einem versteckten Nummer. Die Zahlen reichen von 1 bis 12. </li><li> Themen werden dann in den Laborraum, die mit insgesamt 36 Computer-Arbeitsplätzen ausgestattet ist genommen. Themen sind angewiesen zu suchen und setzen durch den Arbeitsplatz mit der gleichen Nummer versehen wie auf der Karte, die sie am Eingang zog angegeben. </li><li> Alle Themen lesen und unterschreiben die Einverständniserklärung. </li><li> Wir messen Baseline Speichel Testosteron und Cortisol-Konzentrationen mit dem IBL SaliCaps Kit (IBL-Hamburg, Hamburg, Deutschland) für Speichel Probenentnahme. Themen werden gebeten, 1 ml Speichel in die Reagenzgläser, die dann sofort bei -80 ° C eingefroren Transfer </li><li> Themen werden gebeten, die sublinguale Tablette in den Mund zu nehmen, es zu kauen und halten Sie die zerfallen Substanz in ihrem Mund eine Minute lang. Um dies zu erreichen maximale Kontakt des HP-β-CD Testosteron Einschlussverbindung mit der Mundschleimhaut, sind Themen angewiesen, kreisenden Bewegungen mit der Zunge zu machen. Nach einer Minute ist der Rest der Substanz verschluckt mit 100 ml Wasser. </li><li> Unmittelbar nach der Substanz Verwaltung, sind als Pflichtfächer zu verschiedenen Fragebögen ausgefüllt werden. Wir messen Stimmung und Erregung durch die Multidimensional Mood Questionnaire (MDBF) 8 und Angst und Wut Eigenschaften und Zustände, durch die State-Trait Anxiety Inventory 9 und die State-Trait Wut Expression Inventar 10. Diese Fragebögen haben den Zweck, die Kontrolle für eventuelle Auswirkungen der Probanden zufällige Laune, Ärger und Angstzuständen sowie Persönlichkeitsmerkmale. Darüber hinaus komplette Themen der validierten deutschen Versionen der 90-Punkt Symptom Checklist (revidierte Fassung) 11, um ihre psychische Gesundheit zu messen. Diejenigen, die eine sehr hohe Punktzahl (zwei Standardabweichungen über dem Mittelwert, was eine schlechte psychische Gesundheit) haben sich aus der Datenanalyse ausgeschlossen. Aufgrund der bewährten Verzögerung von 4 Stunden für das Auftreten von Wirkungen auf das Verhalten nach der sublingualen Applikation von 0,5 mg Testosteron bei jungen, gesunden Frauen 6,7, ist eine lange Wartezeit ein integraler Bestandteil unserer Studie. Während dieser Zeit sind unsere Themen benötigt, um in den Laborraum bleiben und zu halten sich still besetzt. Damit soll sichergestellt werden, dass keine soziale Interaktion außerhalb des Labors statt, die Anlass zu verwechseln Maßnahmen geben könnte dauert. </li></ol> 3. Ultimatum Game <ol><li> Themen erhalten dann die Anweisungen für ihre Rolle in dem Spiel und die Auszahlung Regeln auf Papier und werden gebeten, sie zu lesen. Wir prüfen ihr Verständnis der Auszahlung Struktur, indem sie vollständige Kontrolle mehrere Fragen am Ende der Anweisungen. </li><li> Wir haben dann einen Überblick über die experimentellen Verfahren mündlich. Der Grund dafür ist, um sicherzustellen, dass die Probanden wissen, dass alle anderen die gleichen Informationen über die Struktur des Spiels hat und wie die Auszahlungen are ermittelt, die auch als &quot;common knowledge&quot; bezeichnet. Die Zusammenfassung ist wie folgt: </li><li> &quot;Das Ultimatum Spiel wird mit zwei Arten von Spielern, einem Antragsteller und einem Responder, die über die Aufteilung von 10 Geldeinheiten (MUS) stimmen gespielt haben. Der Antragsteller kann über die Verteilung der 10 BEs zu entscheiden. In diesem Experiment wurde die Antragsteller können Angebote von 5, 3, 2, oder 0 BEs an den Responder vorzuschlagen. Der Responder muss dann entweder annehmen oder ablehnen diesen Vorschlag. Wenn der Responder akzeptiert der Antragsteller das Angebot, die vorgeschlagene Aufteilung umgesetzt wird und bezahlt werden. Doch die Responder können auch den Vorschlag ablehnen, in diesem Fall keine Partei verdient nichts. &quot; </li><li> Wir sorgen für eine klare Trennung zwischen einem Angebot, das als fair (5 BEs) und Angebote, wie wahrgenommen werden betrachtet ist unfair (3, 2 oder 0 MUs) durch die Beschränkung der Angebote bis 5, 3, 2 oder 0 Mus. Themen werden nach dem Zufallsprinzip und anonym an die Rolle der entweder der Antragsteller oder der Responder zugeordnet und bleiben dann in dieser Rolle für das gesamte Experiment. Jeder Antragsteller macht drei Vorschläge über die Verteilung von mE, während mit drei verschiedenen zufällig ausgewählten Interaktionspartner gekoppelt. Kein Paar von Themen interagiert mehr als einmal. Sie lernen es nie die Identität der Personen, mit denen sie im Experiment abgestimmt. Der Antragsteller erhält keine Rückmeldung über den Respondern &quot;Auswahl bis zum Ende des Experiments. Alle Entscheidungen im Ultimatum-Spiel sind in zTree Software implementiert und präsentiert auf Computer-Bildschirmen 12. </li><li> Weil Testosteron ist eines der meistdiskutierten Hormone in der Boulevardpresse ist es möglich, dass die Probanden einer vorgeformten Glauben (wahr oder falsch) über ihre Auswirkungen 13 haben. Darüber hinaus, weil ethische Bedenken Forscher benötigen, um Themen, die sie erhalten entweder ein Placebo oder Testosteron das Vorwissen über Testosteron eine mögliche Auswirkungen von Testosteron auf das Verhalten belasten können zu informieren. Deshalb bewerten wir die wahrgenommenen Gruppenzugehörigkeit, indem er die Themen, ob sie denken, sie haben Testosteron oder der Placebo-Pille erhalten. </li><li> Die empfundene Gruppenzugehörigkeit ist in den letzten Fragebogen zusammen mit ein paar sozioökonomischen Merkmalen erfasst. In den letzten Fragebogen erstellen wir Probanden Zahlung. </li></ol> 4. Betreff Payment <ol><li> Probanden eine Grundgebühr von hundert Franken für die Teilnahme am Experiment. Die Verwendung von Echtzeit monetäre Anreize reduziert eine mögliche soziale Erwünschtheit Voreingenommenheit und voreingenommen Selbstwahrnehmung. Daher erhält jeder Probanden einen Schweizer Franken (ca. 1 US $) für jede MU im Ultimatum-Spiel verdient. Jeder Patient erhält seine Einnahmen aus der Grundgebühr plus den verdienten BEs in private am Ende des Experiments. </li></ol>

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A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+Androgen+Stimulation+and+Aggressive+Behavior+in+Male+and+Female+Mice.">Early Androgen Stimulation and Aggressive Behavior in Male and Female Mice.</a> Physiology &#38; Behav. 4, 333-338 (1969).</li><li>Archer, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testosterone+and+human+aggression:+an+evaluation+of+the+challenge+hypothesis.">Testosterone and human aggression: an evaluation of the challenge hypothesis.</a> Neurosci Biobehav R. 30, 319-345 (2006).</li><li>Mazur, A., Booth, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testosterone+and+dominance+in+men.">Testosterone and dominance in men.</a> Behav Brain Sci. 21, 353-363 (1998).</li><li>Josephs, R. A., Newman, M. L., Brown, R. P., Beer, J. 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S., Schutter, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testosterone+reduces+unconscious+fear+but+not+consciously+experienced+anxiety:+implications+for+the+disorders+of+fear+and+anxiety.">Testosterone reduces unconscious fear but not consciously experienced anxiety: implications for the disorders of fear and anxiety.</a> Biol Psychiatry. 58, 218-225 (2005).</li><li>Steyer, R., Schwenkmezger, P., Notz, P., Eid, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Der Mehrdimensionale Befindlichkeitsfragebogen (MDBF) [Multidimensional Mood Questionnaire. , (1997).</li><li>Laux, L., Glanzmann, P., Schaffner, P., Spielberger, C. 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Ein Indiz dafür, dass die Ergebnisse gültig sind, wenn die durchschnittliche bietet beobachtet wird, ähnlich wie andere Studien gefunden. Typischerweise sind die durchschnittlichen bietet zwischen 30 bis 40% des Gesamtbetrages und etwa die Hälfte der Probanden bieten die gleichen Anteil 14. Auf der anderen Seite, ist ein Indikator dafür, dass wahrscheinlich Probanden nicht verstehen, die Regeln des Spiels, wenn Angebote von mehr als 50% beobachtet werden. Es ist bemerkenswert, aber dass es eine beträcht...

combining behavioral endocrinology and experimental economics: testosterone and social decision making

Behavioral endokrinologischen Forschung am Menschen sowie bei Tieren lässt vermuten, dass Testosteron spielt eine wichtige Rolle in sozialen Interaktionen. Studien an Nagetieren haben einen direkten Zusammenhang zwischen Testosteron und aggressives Verhalten 1 und Volksweisheit passt diese Befunde auf den Menschen gezeigt, was darauf hindeutet, dass Testosteron induziert unsozial, egoistisch oder gar aggressives Verhalten 2. Allerdings bezweifeln viele Forscher eine direkte Testosteron-Aggressions-Link in den Menschen, argumentierte vielmehr, dass Testosteron in erster Linie in den Status-bezogenen Verhalten 3,4 beteiligt. Da ein hoher Status kann auch von aggressiven und antisozialen Mitteln erreicht werden kann es schwierig sein, zwischen anti-sozialen und Status sucht Verhalten zu unterscheiden. Wir setzen daher auf eine experimentelle Umgebung, in welchem ​​Status kann nur durch prosoziales Mitteln erreicht werden. In einer doppelblinden und plazebo-kontrollierten Experiment, wir eine einzelne sublinguale Dosis von 0,5 mg Testosteron (mit einem Hydroxypropyl-β-Cyclodextrin-Träger) auf 121 Frauen angewendet und untersucht ihre soziale Interaktion Verhalten in eine wirtschaftliche Verhandlungsmacht Paradigma. Echte monetäre Anreize auf dem Spiel stehen in diesem Paradigma, jeder Spieler A erhält eine bestimmte Menge an Geld und hat ein Angebot an einen anderen Spieler B zu machen, wie man das Geld teilen. Wenn B akzeptiert, bekommt sie, was angeboten wurde und Spieler A hält den Rest. Wenn B lehnt das Angebot, bekommt niemand etwas. A-Status der Suche nach Spieler A wird erwartet, um zu vermeiden, indem sie sich prosoziales Weise abgelehnt, dh, indem es höhere Angebote. Die Ergebnisse zeigen, dass, wenn die Erwartungen über das Hormon für kontrolliert werden, Testosteron Verwaltung zu einem signifikanten Anstieg des Fair Tarifverhandlungen führt, bietet im Vergleich zu Placebo. Die Rolle der Erwartungen ist in der Tatsache, dass die Personen, dass sie erhalten Testosteron haben, glauben Bericht niedrigere Angebote zu machen, als diejenigen, die sie glauben, dass sie mit einem Placebo behandelt wurden, sagen, wider. Diese Befunde legen nahe, dass die experimentelle Ökonomik Ansatz empfindlich zum Nachweis von neurobiologischen Auswirkungen so subtil wie die durch die Verabreichung von Hormonen erreicht wird. Ferner weisen die Ergebnisse auf die Bedeutung sowohl psychosoziale als auch neuroendokrine Faktoren bei der Bestimmung der Einfluss von Testosteron auf die menschliche Sozialverhalten.

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Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making

Das Verfahren in diesem Protokoll beschriebenen zeigt, dass Testosteron Verwaltung und Volksglauben über Testosteron mit genau entgegengesetzten sozialen Verhaltensweisen assoziiert sein kann.

Die Kombination Behavioral Endokrinologie und Experimentelle Wirtschaftsforschung: Testosteron und Social Decision Making

Behavioral endocrinological research in humans as well as in animals suggests that testosterone plays a key role in social interactions. Studies in ...

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15.0K Aufrufe.  University of Zurich. Das Verfahren in diesem Protokoll beschriebenen zeigt, dass Testosteron Verwaltung und Volksglauben über Testosteron mit genau entgegengesetzten sozialen Verhaltensweisen assoziiert sein kann.

Serie: Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making

Combining Computer Game-Based Behavioural Experiments With High-Density EEG and Infrared Gaze Tracking

Experimental paradigms are valuable insofar as the timing and other parameters of their stimuli are well specified and controlled, and insofar as they yield data relevant to the cognitive processing that occurs under ecologically valid conditions. These two goals often are at odds, since well controlled stimuli often are too repetitive to sustain subjects' motivation. Studies employing electroencephalography (EEG) are often especially sensitive to this dilemma between ecological validity and experimental control: attaining sufficient signal-to-noise in physiological averages demands large numbers of repeated trials within lengthy recording sessions, limiting the subject pool to individuals with the ability and patience to perform a set task over and over again. This constraint severely limits researchers' ability to investigate younger populations as well as clinical populations associated with heightened anxiety or attentional abnormalities. Even adult, non-clinical subjects may not be able to achieve their typical levels of performance or cognitive engagement: an unmotivated subject for whom an experimental task is little more than a chore is not the same, behaviourally, cognitively, or neurally, as a subject who is intrinsically motivated and engaged with the task. A growing body of literature demonstrates that embedding experiments within video games may provide a way between the horns of this dilemma between experimental control and ecological validity. The narrative of a game provides a more realistic context in which tasks occur, enhancing their ecological validity (Chaytor &amp; Schmitter-Edgecombe, 2003). Moreover, this context provides motivation to complete tasks. In our game, subjects perform various missions to collect resources, fend off pirates, intercept communications or facilitate diplomatic relations. In so doing, they also perform an array of cognitive tasks, including a Posner attention-shifting paradigm (Posner, 1980), a go/no-go test of motor inhibition, a psychophysical motion coherence threshold task, the Embedded Figures Test (Witkin, 1950, 1954) and a theory-of-mind (Wimmer &amp; Perner, 1983) task. The game software automatically registers game stimuli and subjects' actions and responses in a log file, and sends event codes to synchronise with physiological data recorders. Thus the game can be combined with physiological measures such as EEG or fMRI, and with moment-to-moment tracking of gaze. Gaze tracking can verify subjects' compliance with behavioural tasks (e.g. fixation) and overt attention to experimental stimuli, and also physiological arousal as reflected in pupil dilation (Bradley et al., 2008). At great enough sampling frequencies, gaze tracking may also help assess covert attention as reflected in microsaccades - eye movements that are too small to foveate a new object, but are as rapid in onset and have the same relationship between angular distance and peak velocity as do saccades that traverse greater distances. The distribution of directions of microsaccades correlates with the (otherwise) covert direction of attention (Hafed &amp; Clark, 2002).

Procedures for recording high-density EEG and gaze data during computer game-based cognitive tasks are described. Using a video game to present cognitive tasks enhances ecological validity without sacrificing experimental control.

Die Kombination Computer Game-Based Behavioural Experimente mit High-Density EEG-und Infrarot-Tracking-Gaze

Experimental paradigms are valuable insofar as the timing and other parameters of their stimuli are well specified and controlled, and insofar as they ...

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Brain Imaging Investigation of the Neural Correlates of Observing Virtual Social Interactions

The ability to gauge social interactions is crucial in the assessment of others&#x2019; intentions. Factors such as facial expressions and body language affect our decisions in personal and professional life alike 1. These "friend or foe" judgements are often based on first impressions, which in turn may affect our decisions to "approach or avoid". Previous studies investigating the neural correlates of social cognition tended to use static facial stimuli 2. Here, we illustrate an experimental design in which whole-body animated characters were used in conjunction with functional magnetic resonance imaging (fMRI) recordings. Fifteen participants were presented with short movie-clips of guest-host interactions in a business setting, while fMRI data were recorded; at the end of each movie, participants also provided ratings of the host behaviour. This design mimics more closely real-life situations, and hence may contribute to better understanding of the neural mechanisms of social interactions in healthy behaviour, and to gaining insight into possible causes of deficits in social behaviour in such clinical conditions as social anxiety and autism 3.

This article demonstrates an experimental design in which whole-body animated characters are used in conjunction with functional magnetic resonance imaging (fMRI) to investigate the neural correlates of observing virtual social interactions.

Brain Imaging Untersuchung der neuronalen Korrelate von Observing virtuellen sozialen Interaktionen

The ability to gauge social interactions is crucial in the assessment of others&#x2019; intentions. Factors such as facial expressions and body language ...

Measuring the Subjective Value of Risky and Ambiguous Options using Experimental Economics and Functional MRI Methods

Most of the choices we make have uncertain consequences. In some cases the probabilities for different possible outcomes are precisely known, a condition termed "risky". In other cases when probabilities cannot be estimated, this is a condition described as "ambiguous". While most people are averse to both risk and ambiguity1,2, the degree of those aversions vary substantially across individuals, such that the subjective value of the same risky or ambiguous option can be very different for different individuals. We combine functional MRI (fMRI) with an experimental economics-based method3 to assess the neural representation of the subjective values of risky and ambiguous options4. This technique can be now used to study these neural representations in different populations, such as different age groups and different patient populations.
In our experiment, subjects make consequential choices between two alternatives while their neural activation is tracked using fMRI. On each trial subjects choose between lotteries that vary in their monetary amount and in either the probability of winning that amount or the ambiguity level associated with winning. Our parametric design allows us to use each individual's choice behavior to estimate their attitudes towards risk and ambiguity, and thus to estimate the subjective values that each option held for them. Another important feature of the design is that the outcome of the chosen lottery is not revealed during the experiment, so that no learning can take place, and thus the ambiguous options remain ambiguous and risk attitudes are stable. Instead, at the end of the scanning session one or few trials are randomly selected and played for real money. Since subjects do not know beforehand which trials will be selected, they must treat each and every trial as if it and it alone was the one trial on which they will be paid. This design ensures that we can estimate the true subjective value of each option to each subject. We then look for areas in the brain whose activation is correlated with the subjective value of risky options and for areas whose activation is correlated with the subjective value of ambiguous options.

Using functional MRI and behavioral methods to determine the neural representation of the subjective value of risky and ambiguous options in the human brain.

Messung des subjektiven Wert des Risky und mehrdeutig Optionen mit Experimental Economics and Functional MRI Methoden

Most of the choices we make have uncertain consequences. In some cases the probabilities for different possible outcomes are precisely known, a condition ...

C. elegans Tracking and Behavioral Measurement

We have developed instrumentation, image processing, and data analysis techniques to quantify the locomotory behavior of C. elegans as it crawls on the surface of an agar plate. For the study of the genetic, biochemical, and neuronal basis of behavior, C. elegans is an ideal organism because it is genetically tractable, amenable to microscopy, and shows a number of complex behaviors, including taxis, learning, and social interaction1,2. Behavioral analysis based on tracking the movements of worms as they crawl on agar plates have been particularly useful in the study of sensory behavior3, locomotion4, and general mutational phenotyping5. Our system works by moving the camera and illumination system as the worms crawls on a stationary agar plate, which ensures no mechanical stimulus is transmitted to the worm. Our tracking system is easy to use and includes a semi-automatic calibration feature. A challenge of all video tracking systems is that it generates an enormous amount of data that is intrinsically high dimensional. Our image processing and data analysis programs deal with this challenge by reducing the worms shape into a set of independent components, which comprehensively reconstruct the worms behavior as a function of only 3-4 dimensions6,7. As an example of the process we show that the worm enters and exits its reversal state in a phase specific manner.

C. elegans Tracking and Behavioral Measurement

We have developed a video-rate tracking microscope system that can record and quantify C. elegans behavior at high resolution and high speeds. We have also developed computational methods to reduce the dimensionality of the worm images to a fundamental set of measurements that completely describe the shape of the worm.

C. elegans Tracking und Behavioral Measurement

We have developed instrumentation, image processing, and data analysis techniques to quantify the locomotory behavior of C. elegans as it crawls on the ...

A Low Cost Setup for Behavioral Audiometry in Rodents

In auditory animal research it is crucial to have precise information about basic hearing parameters of the animal subjects that are involved in the experiments. Such parameters may be physiological response characteristics of the auditory pathway, e.g. via brainstem audiometry (BERA). But these methods allow only indirect and uncertain extrapolations about the auditory percept that corresponds to these physiological parameters. To assess the perceptual level of hearing, behavioral methods have to be used. A potential problem with the use of behavioral methods for the description of perception in animal models is the fact that most of these methods involve some kind of learning paradigm before the subjects can be behaviorally tested, e.g. animals may have to learn to press a lever in response to a sound. As these learning paradigms change perception itself 1,2 they consequently will influence any result about perception obtained with these methods and therefore have to be interpreted with caution. Exceptions are paradigms that make use of reflex responses, because here no learning paradigms have to be carried out prior to perceptual testing. One such reflex response is the acoustic startle response (ASR) that can highly reproducibly be elicited with unexpected loud sounds in na&iuml;ve animals. This ASR in turn can be influenced by preceding sounds depending on the perceptibility of this preceding stimulus: Sounds well above hearing threshold will completely inhibit the amplitude of the ASR; sounds close to threshold will only slightly inhibit the ASR. This phenomenon is called pre-pulse inhibition (PPI) 3,4, and the amount of PPI on the ASR gradually depends on the perceptibility of the pre-pulse. PPI of the ASR is therefore well suited to determine behavioral audiograms in na&iuml;ve, non-trained animals, to determine hearing impairments or even to detect possible subjective tinnitus percepts in these animals. In this paper we demonstrate the use of this method in a rodent model (cf. also ref. 5), the Mongolian gerbil (Meriones unguiculatus), which is a well know model species for startle response research within the normal human hearing range (e.g. 6).

A fast and inexpensive method for the behavioral determination of hearing parameters like hearing thresholds, hearing impairments or phantom perceptions (subjective tinnitus) is described. It uses pre-pulse inhibition of the acoustic startle response and can be easily implemented in a personal computer using a programmable AD/DA-converter and a piezo sensor.

Ein Low-Cost-Setup für Verhaltensaudiometrie in Nagetiere

In auditory animal research it is crucial to have precise information about basic hearing parameters of the animal subjects that are involved in the ...

Hippocampal Insulin Microinjection and In vivo Microdialysis During Spatial Memory Testing

Glucose metabolism is a useful marker for local neural activity, forming the basis of methods such as 2-deoxyglucose and functional magnetic resonance imaging. However, use of such methods in animal models requires anesthesia and hence both alters the brain state and prevents behavioral measures. An alternative method is the use of in vivo microdialysis to take continuous measurement of brain extracellular fluid concentrations of glucose, lactate, and related metabolites in awake, unrestrained animals. This technique is especially useful when combined with tasks designed to rely on specific brain regions and/or acute pharmacological manipulation; for example, hippocampal measurements during a spatial working memory task (spontaneous alternation) show a dip in extracellular glucose and rise in lactate that are suggestive of enhanced glycolysis1-3,4-5, and intrahippocampal insulin administration both improves memory and increases hippocampal glycolysis6. Substances such as insulin can be delivered to the hippocampus via the same microdialysis probe used to measure metabolites. The use of spontaneous alternation as a measure of hippocampal function is designed to avoid any confound from stressful motivators (e.g. footshock), restraint, or rewards (e.g. food), all of which can alter both task performance and metabolism; this task also provides a measure of motor activity that permits control for nonspecific effects of treatment. Combined, these methods permit direct measurement of the neurochemical and metabolic variables regulating behavior.

Hippocampal Insulin Microinjection and In vivo Microdialysis During Spatial Memory Testing

Modulation of hippocampally-dependent spatial working memory by direct intrahippocampal microinjection, accompanied and followed by in vivo microdialysis for metabolites in conscious, behaving animals.

Hippocampus Insulin Mikroinjektion und<em&gt; In vivo</em&gt; Microdialysis Während Spatial Memory Testing

Glucose metabolism is a useful marker for local neural activity, forming the basis of methods such as 2-deoxyglucose and functional magnetic resonance ...

Effects of Transcranial Alternating Current Stimulation on the Primary Motor Cortex by Online Combined Approach with Transcranial Magnetic Stimulation

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific frequency and in turn modulate ongoing cortical oscillatory activity. This neurotool allows the establishment of a causal link between endogenous oscillatory activity and behavior. Most of the tACS studies have shown online effects of tACS. However, little is known about the underlying action mechanisms of this technique because of the AC-induced artifacts on Electroencephalography (EEG) signals. Here we show a unique approach to investigate online physiological frequency-specific effects of tACS of the primary motor cortex (M1) by using single pulse Transcranial Magnetic Stimulation (TMS) to probe cortical excitability changes. In our setup, the TMS coil is placed over the tACS electrode while Motor Evoked Potentials (MEPs) are collected to test the effects of the ongoing M1-tACS. So far, this approach has mainly been used to study the visual and motor systems. However, the current tACS-TMS setup can pave the way for future investigations of cognitive functions. Therefore, we provide a step-by-step manual and video guidelines for the procedure.

Transcranial Alternating Current Stimulation (tACS) allows the modulation of cortical excitability in a frequency-specific fashion. Here we show a unique approach which combines online tACS with single pulse Transcranial Magnetic Stimulation (TMS) in order to "probe" cortical excitability by means of Motor Evoked Potentials.

Effekte der transkraniellen Wechselstrom Stimulation auf Primärbewegungsrinde durch Online-kombinierter Ansatz mit Transcranial magnetische Anregung

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific ...

Operant Protocols for Assessing the Cost-benefit Analysis During Reinforced Decision Making by Rodents

Reinforcement-guided decision making is the ability to choose between competing courses of action based on the relative value of the benefits and their consequences. This process is integral to the normal human behavior and has been shown to be disrupted by neurological and psychiatric disorders such as addiction, schizophrenia, and depression. Rodents have long been used to uncover the neurobiology of human cognition. To this end, several behavioral tasks have been developed; however, most are non-automated and are labor-intensive. The recent development of the open-source microcontroller has enabled researchers to automate operant-based tasks for assessing a variety of cognitive tasks, standardizing the stimulus presentation, improving the data recording and consequently, improving the research output. Here, we describe an automated delay-based reinforcement-guided decision-making task, using an operant T-maze controlled by custom-written software programs. Using these decision-making tasks, we show the changes in the local field potential activities in the anterior cingulate cortex of a rat whilst it performs a delay-based cost-and-benefit decision-making task.

A cost-benefit analysis is a weighing-scale approach that the brain performs during the course of decision making. Here, we propose a protocol to train rats on an operant-based decision-making paradigm where rats choose higher rewards at the expense of waiting for 15 s to receive them.

Operant Protokolle für die Beurteilung der Kosten / Nutzen-Analyse während verstärkte Entscheidungsfindung durch Nagetiere

Reinforcement-guided decision making is the ability to choose between competing courses of action based on the relative value of the benefits and their ...

Abbiategrasso Brain Bank Protocol for Collecting, Processing and Characterizing Aging Brains

In a constantly aging population, the prevalence of neurodegenerative disorders is expected to rise. Understanding disease mechanisms is the key to find preventive and curative measures. The most effective way to achieve this is through direct examination of diseased and healthy brain tissue. The authors present a protocol to obtain, process, characterize and store good quality brain tissue donated by individuals registered in an antemortem brain donation program. The donation program includes a face-to-face empathic approach to people, a collection of complementary clinical, biological, social and lifestyle information and serial multi-dimensional assessments over time to track individual trajectories of normal aging and cognitive decline. Since many neurological diseases are asymmetrical, our brain bank offers a unique protocol for slicing fresh specimens. Brain sections of both hemispheres are alternately frozen (at -80 &#176;C) or fixed in formalin; a fixed slice on one hemisphere corresponds to a frozen one on the other hemisphere. With this approach, a complete histological characterization of all frozen material can be obtained, and omics studies can be performed on histologically well-defined tissues from both hemispheres thus offering a more complete assessment of neurodegenerative disease mechanisms. Correct and definite diagnosis of these diseases can only be achieved by combining the clinical syndrome with the neuropathological evaluation, which often adds important etiological clues necessary to interpret the pathogenesis. This method can be time consuming, expensive and limited as it only covers a limited geographical area. Regardless of its limitations, the high degree of characterization it provides can be rewarding. Our ultimate goal is to establish the first Italian Brain Bank, all the while emphasizing the importance of neuropathologically verified epidemiological studies.

This protocol describes a method to track individual brain-aging trajectories through a brain donation program and proper characterization of brains. Brain donors are involved in a long-term longitudinal study including serial multi-dimensional assessments. The protocol contains a detailed description of brain processing and an accurate diagnostic methodology.

Abbiategrasso Brain Bank Protocol zum Sammeln, Verarbeiten und Charakterisieren alternder Gehirne

In a constantly aging population, the prevalence of neurodegenerative disorders is expected to rise. Understanding disease mechanisms is the key to find ...

Post-Movie Subliminal Measurement (PMSM), for Investigating Implicit Social Bias

New knowledge is continuously gained from a social environment that can influence how people respond to each other. Such responses often occur implicitly, at a subliminal perceptual level, and related brain mechanisms can be experimentally isolated by presenting the stimuli quickly. Subliminal presentation of faces that belong to different ethnicity groups, races, or gender has been shown to be successful in investigating social implicit responses. However, many implicit responses are based on knowledge previously gained about the faces (e.g., sexual orientation, political views, and socioeconomic status) and not solely on physical appearance. Here, a novel method called post-movie subliminal measurement (PMSM) is presented. When watching a socially engaging movie, a spectator gains knowledge about the protagonist and becomes familiar with his/her identity and world views. When the face of the protagonist is presented subliminally after the movie, it evokes an implicit neural response depending on what is learned about the protagonist. With a vast number of movies available, each depicting a variety of people with different identities, the PMSM method enables investigation of the brain&#39;s complex implicit biases in a manner that resembles real-life social perceptions.

Post-Movie Subliminal Measurement PMSM, for Investigating Implicit Social Bias

This protocol describes the use of movies to investigate brain mechanisms underlying implicit social biases during functional magnetic resonance imaging. When the face of a protagonist is presented after a movie subliminally, it evokes an implicit response based on knowledge of the protagonist gained during the movie.

Post-Movie Subliminal Measurement (PMSM), zur Untersuchung impliziter sozialer Voreingenommenheit

New knowledge is continuously gained from a social environment that can influence how people respond to each other. Such responses often occur implicitly, ...