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Environmental and marine conservation management pose significant challenges for decision-making. These arise not only from the numerous urgent issues confronting decision-makers but also from the uncertainties in our understanding of ecosystem functions and their responses to stressors. Value of information (VoI) theory provides a framework for evaluating the impact of these uncertainties on management decisions from the perspective of the decision-maker. VoI is becoming increasingly relevant in environmental and ecosystem management. As a decision-analytic tool, VoI quantifies the advantages of acquiring additional information to enhance decision-making processes. It assists decision-makers in selecting the optimal management strategy and determining whether immediate action is necessary or if it is beneficial to delay and invest in further data collection and research. This thesis contributes to the understanding of VoI and its application to decision problems in environmental and ecosystem management.

The effects of soil disturbance caused by the European mole (Talpa europaea, LINNAEUS 1758) on microbial decomposition of organic litter, microbial biomass C and N and concentrations of nitrate and ammonium were examined based on data collected from three sample plots in the botanical garden of the University of Oldenburg, Germany. Compared to the undisturbed pasture, molehills were characterized by a warmer microclimate, higher bulk density, lower concentrations of organic C and N as well as by reduced water contents. The effects on microbial biomass C and N were negative across all sample plots. Effects on microbial decomposition of organic litter showed no clear trend with one sample plot showing a positive effect whereas others showed no effect or a negative effect. There was no statistically significant difference in concentrations of nitrate and ammonium between molehills and undisturbed pasture except for one sample plot where nitrate concentrations were reduced in molehills. It is suggested that microbial decomposition was influenced by microclimatic differences between the sample plots which were the result of differences in shading. The overall effects of shading and water content on microbial decomposition were greater than those of molehill disturbance. Effects on microbial biomass C and N were negative, likely due to the absence of a rhizosphere and reduced concentrations of organic C and N in molehills. Molehill disturbance likely has a positive effect on N-mineralization due to the destruction of soil aggregates, explaining the lack of differences between molehills and undisturbed pasture in nitrate and ammonium concentrations. Future studies should examine effects of microclimate on microbial activity in molehills in relationship to soil water content. Der Einfluss von durch den Europäischen Maulwurf (Talpa europaea, LINNAEUS 1758) hervorgerufenen Störungen auf den mikrobiellen Abbau organischer Streu, die mikrobielle Biomasse und den mineralischen S

The topographic complexity of the mouse retina, which lacks features like the fovea, has long been underestimated. However, recent evidence has revealed anatomical and functional gradients in different retinal cell types, such as bipolar and ganglion cells. Much less is known about the topographic variations in horizontal cells. These cells form large, gap junction-coupled networks and provide feedback to photoreceptors and feedforward signaling to bipolar cells, thereby creating the antagonistic receptive fields of downstream neurons. Using intracellular injections, this thesis investigated regional specializations in mouse horizontal cells and found topographic variations, for example in gap junction coupling. These variations likely result in different spatial scales of how horizontal cells provide feedback to postsynaptic cells and may underlie the different response properties previously reported for dorsal and ventral retinal ganglion cells.

Ökologische Gemeinschaften weisen aufgrund zahlreicher Wechselwirkungen regelmäßig komplexe nichtlineare Dynamiken auf. Angesichts des Klimawandels und des Verlusts der biologischen Vielfalt ist das Verständnis der anthropogenen Auswirkungen auf mikrobielle Gemeinschaften eine wichtige Herausforderung unserer Zeit. In dieser Arbeit wird ein zweigeteilter Ansatz verfolgt, um das Verständnis der Mechanismen von komplexen ökologischen Gemeinschaften zu verbessern. Diffusion maps identifizieren wichtige metabolische Nischen in einer Langzeitdatenreihe von Bakteriengemeinschaften und reduzieren damit die Dimensionalität dieses Datensatzes. Im zweiten Teil wird ein verallgemeinerter Modellierungsansatz angewandt, um die wechselseitige Ernährung in bakteriellen Gemeinschaften zu untersuchen. Insgesamt bieten diese Fortschritte bei der Datenanalyse und Modellierung Einblicke in die Mechanismen, die Zusammensetzung und die Dynamiken mikrobieller Gemeinschaften und deren Auswirkungen auf das Funktionieren von Ökosystemen

Bacteriophages, viruses infecting bacteria, have a strong influence on bacterial community structures and ecosystem functioning in the ocean. Only little is known so far about roseophages, those infecting the important and widespread Roseobacteraceae family. Here, roseophage diversity in the North Sea was investigated by isolation, cultivation and whole genome sequencing. More than 100 new roseophages infecting the ecologically relevant genera Sulfitobacter, Lentibacter, and Octadecabacter have been isolated and genome sequenced, revealing an impressive diversity. The new phages vary in genome size, morphology and lifestyle and could be assigned to eight families in the class Caudoviricetes, comprising four already existing and four newly proposed families. The majority of the new isolates belonged to one large group of highly similar, potentially species-level related Sulfitobacter phages. Host range determination against their original isolation host strains revealed a complex infectivity network. Genome analysis of these phages and of thirty whole-genome sequenced host strains revealed a high degree of microdiversity on both sides.

Retinal degeneration protein 3 (RD3), a protein involved in the trafficking of photoreceptor-specific membrane guanylate cyclases, has recently been identified in other tissue types, suggesting a potentially broader role. However, the pathophysiological role of RD3 and its specific protein targets in tissues other than the retina have not been elucidated. In this thesis, we have characterized the RD3 transcript pattern in mouse neuronal tissues and its function in the inhibition of GC-A and GC-B. Research has also shown that loss of RD3 has diagnostic and prognostic value in glioblastoma. Moreover, RD3 can cause cell cycle arrest and programmed cell death, which may impact by its protein structure mutant. These findings suggest a novel regulatory property of RD3 in hormone receptor in brain and indicate that it may serve as a good model for elucidating neuro-ophthalmologic manifestations in neurological diseases.

In the central auditory system, miR-183 cluster plays crucial roles in auditory brainstem structure development and excitatory synaptic transmission at the calyx of Held. To probe inhibitory synaptic neurotransmission, a miR-183/96 double knockout mouse model was analyzed. Immunohistochemistry revealed significant alterations in Gphn and Gabra1 expression, key regulators of inhibitory neurotransmission. However, expression of other proteins like Kcc2, Hapln4, and Gad2/65 remained unaltered. Moreover, transcriptomic analysis unveiled 34 and 116 differentially expressed genes in LSO and MNTB, respectively. Some of of these genes play vital roles in synaptic transmission and are implicated in hearing loss.These findings underscore the intricate regulatory roles of miRNAs in auditory system development and function and offer insights into potential targets for hearing-related disorders.

Forests affect the water balance and thus deep seepage rates differently depending on species composition. Here, the effect of forest conversion on deep seepage rates is investigated in pure and mixed forests of pine (Pinus sylvestris), beech (Fagus sylvatica) and Douglas fir (Pseudotsuga menziesii) at three groundwater-distant and sandy forest sites in Northwest Germany. Based on continuous meteorological, stand precipitation and soil moisture measurements between January 2019 and October 2020, deep seepage rates are modelled with the hydrological model LWF-Brook90. Compared to pure pine forests, modelled deep seepage rates do not increase in mixed forests, but strongly increase in pure beech forests. The results further indicate that tree thinning increases deep seepage rates significantly. These modelled deep seepage rates serve as a basis for an economic evaluation of groundwater recharge as an ecosystem service to promote groundwater-emphasized forest conversion.

Guanylate cyclase-activating proteins (GCAPs) are neuronal calcium sensors that activate retinal guanylate cyclases (GCs) in a Ca2+-dependent manner. GCAP5 from the retina of the zebrafish (Danio rerio) harbors a non-conserved cysteine cluster at its N-terminal. C15 and C17 prevent a Ca2+-dependent conformational change essential for a Ca2+-dependent regulation of retinal GCs. In exchange, they mediate redox-sensitive regulation. Further, GCAP5 binds ferrous iron with nanomolar affinity (Lim et al. 2017, Biochemistry 56(51): 6652-6661): Two GCAP5 molecules coordinate one ferrous iron with C15 and C17, forming an iron-sulfur cluster in a [Fe(SCys)4] complex. These unusual characteristics of GCAP5 lead to the conclusion that it might be involved in cell protection under oxidative stress conditions.

Neurons communicate via synapses—specialized structures that consist of a presynaptic terminal of one neuron and a postsynaptic terminal of another. As knowledge is emerging that mutations in molecules that regulate synaptic function underpin many neurological disorders, it is crucial to elucidate the molecular mechanisms regulating synaptic function to understand synaptic strength, plasticity, modulation, and pathology, which ultimately impact neuronal circuit output and behavior. The presynaptic calyx of Held is a large glutamatergic presynaptic terminal in the auditory brainstem, which due to its accessibility and the possibility to selectively perform molecular perturbations on it, is an ideal model to study the role of presynaptic proteins in regulating synaptic function. In this protocol, we describe the use of confocal imaging and three-dimensional reconstruction of the calyx of Held to assess alterations in gross morphology following molecular perturbation. Using viral-vector delivery to perform molecular perturbations at distinct developmental time points, we provide a fast and cost-effective method to investigate how presynaptic proteins regulate gross morphology such as surface area and synapse volume throughout the lifetime of a neuronal circuit.

Masking can reduce the efficiency of communication and prey and predator detection. Most underwater sounds fluctuate in amplitude, which may influence the amount of masking experienced by marine mammals. The hearing thresholds of two harbor seals for tonal sweeps (centered at 4 and 32 kHz) masked by sinusoidal amplitude modulated (SAM) Gaussian one-third octave noise bands centered around the narrow-band test sweep frequencies, were studied with a psychoacoustic technique. Masking was assessed in relation to signal duration, (500, 1000, and 2000 ms) and masker level, at eight amplitude modulation rates (1–90 Hz). Masking release (MR) due to SAM compared thresholds in modulated and unmodulated maskers. Unmodulated maskers resulted in critical ratios of 21 dB at 4 kHz and 31 dB at 32 kHz. Masked thresholds were similarly affected by SAM rate with the lowest thresholds and the largest MR being observed for SAM rates of 1 and 2 Hz at higher masker levels. MR was higher for 32-kHz maskers than for 4-kHz maskers. Increasing signal duration from 500 ms to 2000 ms had minimal effect on MR. The results are discussed with respect to MR resulting from envelope variation and the impact of noise in the environment on target signal detection.

Die Biologie kennt alle Eigenschaften des Lebendigen, aber auf die Frage »Was ist Leben?« hat sie keine eindeutige Antwort. Der Grund dafür liegt im Organischen selbst: Seine Struktur folgt zwar kausalen Naturgesetzen, ist aber nicht hinreichend durch sie zu begründen. Wir beurteilen Lebewesen analog zur Technik als zweckmäßig aufgebaut, aber zugleich wissen wir, dass sie natürlich entstanden sind. Christine Zunke analysiert den Widerspruch, Leben über ein teleologisches Prinzip zu erklären und es zugleich nicht zu tun. Mit ihrer naturphilosophischen Reflexion zeigt sie auf, wie dieser Widerspruch das Denken in eine Dialektik des Lebendigen führt – oder zur Quelle biologistischer Ideologie wird.

Mit Hilfe der Genom-Editierung rücken Eingriffe in die menschliche Keimbahn in greifbare Nähe. Ziel der vorliegenden Studie ist die Erhebung der Entwicklung der ethischen Bewertungskompetenz von Jugendlichen zum Kontext der Genom-Editierung. Insgesamt sind 32 Jugendliche befragt und unterrichtet worden. Die unterrichtlichen Interventionen umfassten das Fachwissen zur Genom-Editierung eine Förderung der ethischen Bewertungskompetenz. Zusammengefasst sehen die Jugendlichen dieser Studie die Veränderung der DNA des Ungeborenen als größtes Problem der keimbahnverändernden Genom-Editierung an. Trotz des Risikos der unvorhersehbaren Nebenwirkungen der Genom-Editierung sehen viele Jugendlichen die Chance eines gesunden, leidfreien Lebens. Über die Hälfte der Jugendlichen entscheidet sich gegen den Einsatz einer Genom-Editierung. Der Kontext der Genom-Editierung ermöglicht eine ethische Diskussion und kann im Biologieunterricht zur Förderung der Bewertungskompetenz eingesetzt werden.

Außerschulische Bildung in MINT Schülerlaboren stellt heute eine wichtige Ergänzung zur Schule dar. Um die Qualität der Angebote weiterzuentwickeln, nimmt die Erforschung von Denk und Lernprozessen in MINT Schülerlaboren zu, was auch von Lernort Labor e. V. als Vertretung der MINT Schülerlabore unterstützt wird. Aber nicht immer gelingt es, dass einzelne Schülerlabore mit Forschungsgruppen zusammenarbeiten. Deshalb ist im kooperativen Forschungs- und Entwicklungsprojekts GINT zusammen mit Schülerlaboren dieses Tool entwickelt worden, mit dem sich Schülerlabore selbst beforschen können. Die Elemente des Tools basieren auf den Erhebungsinstrumenten des Forschungsprogramms. Das Tool hilft Betreibenden dabei, die ablaufenden Prozesse im Labor besser zu verstehen, indem Sie einzelne Schülergruppen bei deren Arbeit im Schülerlabor begleiten. Mit Hilfe des Tools erfährt man mehr über die Handlungen, das Denken und die Beweggründe der Schüler:innen und können erkennen, als wie selbständig sich Schüler:innen in Ihrem Schülerlabor wahrnehmen.

Mit der Globalisierung geht auch die Verbreitung von gebietsfremden Arten einher. Bis zum Jahr 2050 wird mit einer Zunahme von bis zu 50 % gegenüber dem heutigen Niveau gerechnet. Diese zukünftigen und die aktuell vorhanden gebietsfremden Arten stellen eine potenzielle Bedrohung für die einheimische Biodiversität dar. In dieser Studie wurden die Verbreitung, die Vergesellschaftung und die Standortbedingungen der invasiven Arten Crassula helmsii (Nadelkraut) und Campylopus introflexus (Kaktusmoos) sowie der potenziell invasiven Art Senecio inaequidens (Schmalblättriges Greiskraut) auf den Ostfriesischen Inseln untersucht und mit früheren Kartierarbeiten verglichen. Mittels der aufgestellten Habitatmodelle war es möglich, die zukünftige Entwicklung dieser Arten aufzuzeigen. Weiterhin wurden der Status Quo der neophytischen Arten auf den Inseln Wangerooge und Mellum sowie dem angrenzten Festland erfasst, um frühzeitig neue Problemarten zu identifizieren.

Das Verhältnis von Theorie und Praxis im Lehramtsstudium ist einer der am häufigsten diskutierten Aspekte im Kontext universitärer Lehrkräftebildung. In der Biologiedidaktik haben sich Lehr-Lern-Labore als Lerngelegenheit für Lehramtsstudierende der Biologie etabliert, um eine Theorie-Praxis-Verzahnung im Lehramtsstudium zu gewährleisten. In der vorliegenden Arbeit wird die Frage untersucht, wie Lehr-Lern-Labore von Lehramtsstudierenden der Biologie als Lerngelegenheit im Lehramtsstudium wahrgenommen und genutzt werden. Dafür wurden Gruppendiskussionen durchgeführt und mittels der Grounded Theory ausgewertet.Die Kernkategorie umfasst das zentrale Phänomen Unterrichten lernen durch „(Nicht)-Unterrichten“. Dies beschreibt, dass Studierende ihr Handeln im Lehr-Lern-Labor häufig nicht als Unterrichten im schulischen Sinne ansehen, aber dennoch typische Unterrichtssituationen im Lehr-Lern-Labor durchleben, welche Ausgangspunkt der Weiterentwicklung professioneller Kompetenzen sein können.

Bacteriophages of the family Microviridae are one of the major clades of ssDNA phages. Their cultivated members are lytic and infect Proteobacteria, Bacteroidetes, and Chlamydiae. Prophages have been predicted in genomes from Bacteroidales, Hyphomicrobiales, and Enterobacteriaceae and cluster within the subfamilies “Alpavirinae”, “Amoyvirinae” and Gokushovirinae. Previously, the bacteriophage “Ascunsovirus oldenburgi” ICBM5 was isolated from the North Sea and is distantly related to known Microviridae. The novel phage infects Sulfitobacter dubius SH24-1b and uses both a lytic and a carrier-state life strategy. An entire infection cycle was analysed in replicates using a combinational approach of one-step growth curves and phage targeted direct-geneFISH. Thereby, the percentage of infected cells as well as the number of viral genomes per cell could be quantified over the course of an infection….

Consequences of climate change threaten the stability of current human land use at the German coast. This thesis explores the effects of alternative sustainable coastal land use strategies designed to provide ecosystem services like water retention or carbon sequestration on breeding and wintering birds. At the German North Sea and Baltic Sea coast, occurrence of breeding birds in relation to vegetation structure, soil parameters, agricultural land use intensity and invertebrate food abundance was investigated. Habitat preferences of wintering geese and the consequences of goose grazing on coastal grasslands for farmers were studied at the North Sea coast. Alternative land use strategies have the potential to offer valuable habitat for endangered breeding birds and mitigate the ongoing goose-agriculture-conflict if management aims and target species are properly defined. Both agricultural intensification and land abandonment will lead to a loss of coastal avian biodiversity.

SERRATE, a multifunctional protein is involved in transcriptional regulation speculatively via transcription factor binding. This study aims at investigating the multiple interacting partners of SE mainly focusing on transcription factors (TF). Y2H library screening and IP-MS revealed 63 TF binding to SE. Confirmatory experiments showed direct interaction of 7 ALFIN1-LIKE proteins, TOE1, TOE2 and IAA34 TF. Co-IP experiments demonstrated that SE binds to AL4, AL5, AL7, TOE1 and IAA34 in planta. al4 al5 al6 al7 mutant was generated via CRISPR-Cas9 to study functional role of SE with TF, which revealed redundancies among alfins. On other hand, se1 toe1 toe2 mutant showed pleiotropic defects though it exhibited no difference in flowering time compared to toe1/2. This indicates TOEs are epistatic to SE. Expression profiles of MIRNAs, their targets and RNA seq analysis of se-1 and toe1/2 showed a speculative role in flowering inhibition during juvenile phase.

he copepod Calanus finmarchicus (Crustacea, Copepoda) is a key zooplanktonic spe- cies with a crucial position in the North Atlantic food web and significant contributor to ocean carbon flux. Like many other high latitude animals, it has evolved a programmed arrested development called diapause to cope with long periods of limited food sup- ply, while growth and reproduction are timed to take advantage of seasonal peaks in primary production. However, anthropogenic warming is inducing changes in the expected timing of phytoplankton blooms, suggesting phenological mismatches with negative consequences for the N. Atlantic ecosystem. While diapause mechanisms are mainly studied in terrestrial arthropods, specifically on laboratory model species, such as the fruit fly Drosophila, the molecular investigations of annual rhythms in wild marine species remain fragmentary. Here we performed a rigorous year-long monthly sampling campaign of C. finmarchicus in a Scottish Loch (UK; 56.45°N, 5.18°W) to generate an annual transcriptome. The mRNA of 36 samples (monthly triplicate of 25 individuals) have been deeply sequenced with an average depth of 137 ± 4 million reads (mean ± SE) per sample, aligned to the reference transcriptome, and filtered. We detail the quality assessment of the datasets and provide a high-quality resource for the investigation of wild annual transcriptomic rhythms (35,357 components) in a key diapausing zooplanktonic species.

Anthropogenic climate change is altering global biogeographical patterns. However, it remains difficult to quantify how bioregions are changing because pre-industrial records of species distributions are rare. Marine microfossils, such as planktonic foraminifera, are preserved in seafloor sediments and allow the quantification of bioregions in the past. Using a recently compiled data set of pre-industrial species composition of planktonic foraminifera in 3802 worldwide seafloor sediments, we employed multivariate and statistical model-based approaches to study spatial turnover in order to 1) quantify planktonic foraminifera bioregions and 2) understand the environmental drivers of species turnover. Four latitudinally banded bioregions emerge from the global assemblage data. The polar and temperate bioregions are bi-hemispheric, supporting the idea that planktonic foraminifera species are not limited by dispersal. The equatorial bioregion shows complex longitudinal patterns and overlaps in sea surface temperature (SST) range with the tropical bioregion. Compositional-turnover models (Bayesian bootstrap generalised dissimilarity models) identify SST as the strongest driver of species turnover. The turnover rate is constant across most of the SST gradient, showing no SST threshold values with rapid shifts in species composition, but decelerates above 25°C, suggesting SST is less predictive of species composition in warmer waters. Other environmental predictors affect species turnover non-linearly, and their importance differs across regions. In the Pacific ocean, net primary productivity below 500 mgC m−2 day−1 drives fast compositional change. Water depth values below 3000 m (which affect calcareous microfossil preservation) increasingly drive changes in species composition among death assemblages in the Pacific and Indian oceans. Together, our results suggest that the dynamics of planktonic foraminifera bioregions are expected to be highly responsive to climate chang

Melanin is a widely distributed and striking dark-colored pigment produced by countless living organisms. Although a wide range of bioactivities have been recognized, there are still major constraints in using melanin for biotechnological applications such as its fragmentary known chemical structure and its insolubility in inorganic and organic solvents. In this study, a bacterial culture of Streptomyces cavourensis SV 21 produced two distinct forms of melanin: (1) a particulate, insoluble form as well as (2) a rarely observed water-soluble form. The here presented novel, acid-free purification protocol of purified particulate melanin (PPM) and purified dissolved melanin (PDM) represents the basis for an in-depth comparison of their physicochemical and biological properties, which were compared to the traditional acid-based precipitation of melanin (AM) and to a synthetic melanin standard (SM). Our data show that the differences in solubility between PDM and PPM in aqueous solutions may be a result of different adjoining cation species, since the soluble PDM polymer is largely composed of Mg2+ ions and the insoluble PPM is dominated by Ca2+ ions. Furthermore, AM shared most properties with SM, which is likely attributed to a similar, acid-based production protocol. The here presented gentler approach of purifying melanin facilitates a new perspective of an intact form of soluble and insoluble melanin that is less chemical altered and thus closer to its original biological form.

Coastal observatories are key to improve the understanding of processes within the coastal area and their interactions with regional and global environmental changes. The land-sea transition zone is an essential area that allows research on unique scientific questions under anthropogenic and natural influences. Amid the Wadden Sea UNESCO world natural heritage site – the largest tidal flat region worldwide – the barrier island Spiekeroog is an excellent location for an observatory studying land-sea interactions. The integrated Spiekeroog Coastal Observatory (SCO) operated by the Institute for Chemistry and Biology of the Marine Environment (ICBM, University of Oldenburg) is dedicated to interdisciplinary marine and terrestrial ecosystem research. Its position within the tidal area and the multitude of research-field addressed establishes the SCO as a unique coastal observatory with the potential to identify patterns in long-term variability and simultaneously understanding short-term changes. The establishment of the Time-Series Station (TSS) Spiekeroog in a tidal channel west of Spiekeroog back in 2002 laid the foundation of the SCO. Since then, the observatory is expanding continuously and is now representing a valuable asset supporting education, industry, government, and environmental conservation efforts in the area. Summing up the infrastructure and technical components, the importance of the SCO is evident, and individual projects greatly benefit from the collaboration with the partners in and the elements of the SCO. Harmonizing the infrastructure and competences of contributing partners will be a next step to further consolidate the SCO. A challenge poses the maintenance of the SCO based on projects, which is focused on the addition of new facilities, not maintaining, refurbishing, or (if necessary) deconstructing existing infrastructure. Therefore, structural support and funding opportunities not linked to projects but aiming to sustain observational capac

Synapses contain a limited number of synaptic vesicles (SVs) that are released in response to action potentials (APs). Therefore, sustaining synaptic transmission over a wide range of AP firing rates and timescales depends on SV release and replenishment. Although actin dynamics impact synaptic transmission, how presynaptic regulators of actin signaling cascades control SV release and replenishment remains unresolved. Rac1, a Rho GTPase, regulates actin signaling cascades that control synaptogenesis, neuronal development, and postsynaptic function. However, the presynaptic role of Rac1 in regulating synaptic transmission is unclear. To unravel Rac1’s roles in controlling transmitter release, we performed selective presynaptic ablation of Rac1 at the mature mouse calyx of Held synapse. Loss of Rac1 increased synaptic strength, accelerated EPSC recovery after conditioning stimulus trains, and augmented spontaneous SV release with no change in presynaptic morphology or AZ ultrastructure. Analyses with constrained short-term plasticity models revealed faster SV priming kinetics and, depending on model assumptions, elevated SV release probability or higher abundance of tightly docked fusion-competent SVs in Rac1-deficient synapses. We conclude that presynaptic Rac1 is a key regulator of synaptic transmission and plasticity mainly by regulating the dynamics of SV priming and potentially SV release probability.

Sound in noise is better detected or understood if target and masking sources originate from different locations. Mammalian physiology suggests that the neurocomputational process that underlies this binaural unmasking is based on two hemispheric channels that encode interaural differences in their relative neuronal activity. Here, we introduce a mathematical formulation of the two-channel model – the complex-valued correlation coefficient. We show that this formulation quantifies the amount of temporal fluctuations in interaural differences, which we suggest underlie binaural unmasking. We applied this model to an extensive library of psychoacoustic experiments, accounting for 98% of the variance across eight studies. Combining physiological plausibility with its success in explaining behavioral data, the proposed mechanism is a significant step towards a unified understanding of binaural unmasking and the encoding of interaural differences in general.