The transition to a sustainable society is vital and requires electrification. Sodium and potassium ion-based electrolytes will likely play an important role in energy storage as these elements are very abundant. The latter cations and chloride are especially interesting since life on the planet is somehow based on biological transfers of these ions through cell membranes. K+ is the key charge carrier in plants. Here, we characterize electrochemically, electrostatically, and structurally novel electrolytes, K3ClO and K2.99Ba0.005ClO, and compare their performance with Na3ClO and Na2.99Ba0.005ClO in symmetric and asymmetric structural electrode-less cells, such as K/K2.99Ba0.005ClO in a cellulose membrane/K, Na/Na2.99Ba0.005ClO in a cellulose membrane/Na, Al/K2.99Ba0.005ClO composite/Cu, and Al/Na2.99Ba0.005ClO composite/Cu, at temperatures that range from −45 to 65 °C. An ab initio molecular dynamics structural study followed by band structure determination using density functional theory and hybrid simulations allowed us to compare the amorphous character of the structures, bandgap, and electron localization function for both K3ClO at 25 °C and Na3ClO at 37 °C, temperatures at which preliminary studies indicate that these compounds are already amorphous. As in Na+-based electrolytes, the ferroelectric character of the K+-based electrolytes is well recognizable, especially at −45 °C, where the relative real permittivity achieves 1013 in K/K2.99Ba0.005ClO in cellulose membrane/K symmetric cells for an ionic conductivity of ∼120 mS/cm. As in Na+-based electrodes-less structural battery cells, self-charge and self-cycling phenomena are also demonstrated reinforcing the ferroelectric nature of the A3ClO (A = Li, Na, and K) family of electrolytes. These studies may contribute to understanding the K+ and Na+ transfer behavior in energy harvesting and storage as well as the biologic world.

The continuity illusion occurs when visual stimuli are presented at a sufficiently high frequency, thereby triggering a shift from the static to the dynamic vision mode. This facilitates perception of continuous and moving objects, which is key for interactions with the surrounding environment. However, how the continuity illusion is encoded along the entire visual pathway remains poorly understood, with disparate Flicker Fusion Frequency (FFF) measured at the retinal, cortical, and behavioural levels. Here, we combine a behavioural paradigm, functional–MRI (fMRI), and electrophysiological validation for studying the mechanisms underlying the encoding of the continuity illusion effect in the rat. Our behavioural measurements reported a Flicker Fusion Frequency (FFF) of 18±2 Hz. Remarkably, whole–pathway fMRI revealed marked zero–crossings from positive to negative fMRI signal regimes at the FF in the superior colliculus (SC) – an important visual saliency detector – but not in higher cortical or thalamic visual areas. Our electrophysiological recordings in SC explained the sources of these observations as arising from strong neuronal suppression when the continuity illusion is achieved. Combined, our data suggests that activation and suppression balances in SC play a critical role in encoding the continuity illusion effect.

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The underlying sources of negative BOLD responses (NBRs) are still debated. Here, we show rat superior colliculus (SC) NBRs associated with visual stimulation at short inter-stimulus intervals (ISIs) along with decreases in power of local field potentials and multi-unit activity signals measured in this region. This hints to neuronal suppression, possibly due to impossibility of complete excitability recovery upon short ISIs, associated with NBRs. Moreover, both NBRs and electrophysiological power time profiles reveal one peak after stimulus started and another when it ceased, highlighting the SC nature of detecting "brightness changes" when individual flashes are no longer perceivable.

Negative BOLD responses (NBRs) in rat Inferior Colliculus (IC) were recently observed upon monaural auditory stimulation, but their origins and importance remain poorly understood. Intercollicular communication is proposed as a prominent mechanism for auditory processing, including sound localization/lateralization & in gain control regulation. Here, we investigated intercollicular interaction via monoaural stimulation at 9.4T. Rats exhibited NBRs in the ipsilateral IC and positive BOLD responses (PBRs) in the contralteral IC. When the contralateral hemisphere was lesioned, the NBRs vanished in the ipsilateral IC. Our findings suggest that intercollicular interaction is essential for ipsilateral negative BOLD responses and for auditory processing.