Power-integrated, wireless neural recording systems on the cranium using a direct printing method for deep- brain analysis

This is where leaders would look at this and mutter to themselves; 'We could use this to detect brain signals occurring during stroke recovery, neurogenesis and neuroplasticity, and thus figure out how to make those signals repeatable'. But we have to do human testing first.

But the leaders would already have started listening to brain signals using one of these already. 

1. Use nanowires to listen in on single neurons

2. Or lay a grid across the cortex to listen in.

But we have NO stroke leaders, nothing will get done until we get survivors in charge.

Leaders solve problems, they don't run away from them.

The latest here:

 

Power-integrated, wireless neural recording systems on the cranium using a direct printing method for deep- brain analysis

Yong Won Kwon1,2
†, David B. Ahn 3
†, Young-Geun Park1,2
†, Enji Kim1,2
, Dong Ha Lee1,2
,
Sang-Woo Kim3
, Kwon-Hyung Lee4
, Won-Yeong Kim5
, Yeon- Mi Hong1,2
, Chin Su Koh 6
,
Hyun Ho Jung 6
, Jin Woo Chang7
, Sang-Young Lee5*, Jang- Ung Park1,2,6,8*
Conventional power-integrated wireless neural recording devices suffer from bulky, rigid batteries in head mounted configurations, hindering the precise interpretation of the subject’s natural behaviors. These power sources also pose risks of material leakage and overheating. We present the direct printing of a power-integrated wireless neural recording system that seamlessly conforms to the cranium. A quasi–solid-state Zn-ion microbattery was 3D-printed as a built-in power source geometrically synchronized to the shape of a mouse skull. Soft deep-brain neural probes, interconnections, and auxiliary electronics were also printed using liquid metals on the cranium with high resolutions. In vivo studies using mice demonstrated the reliability and biocompatibility of this wireless neural recording system, enabling the monitoring of neural activities across extensive brain regions without notable heat generation. This all-printed neural interface system revolutionizes brain research, providing bioconformable, customizable configurations for improved data quality and naturalistic experimentation.
INTRODUCTION
The brain constitutes an intricate three-dimensional (3D) network composed of an immense number of neurons continually generating and transmitting signals for communication. These neuronal activities and firing patterns play a pivotal role in governing bodily functions, consciousness, and the formation of memories. Comprehending the electrophysiology of neurons and functional connectivity of network-level neuronal activities is essential for fundamental research in the treatment of numerous neurological diseases, such as Parkinson’s disease (PD), Alzheimer’s disease, epilepsy, and major depressive disorder (1). In response to the challenge, implantable electronic devices known as neural probes have seen notable development. These devices are designed to convert neural signals into electronic signals, allowing for the precise monitoring of neuronal activities within specific brain regions (2–6). In particular, recentadvances in microfabrication technologies and bioelectronics have enabled flexible neural probes for reliable recording by ensuring mechanical and structural compatibility with brain tissues (7–12). A predominant perspective in neuroscience and biomedical engineering is that the activities of a neuronal population are notably influenced by the state of the subject. This perspective allows for a better understanding of neuronal computations related to diverse behavioral and cognitive processes, particularly during unrestricted movement and freely movable states (13, 14). However, the use of numerous neural probes connected to external recording devices via cables and wires limits the subject’s freedom of movement. Consequently, wireless neural recording devices have become indispensable to facilitate more natural movements and behaviors in subjects. This is especially crucial in studies aiming to comprehend how the brain responds to specific environments and tasks. In addition, wireless neural recording holds the potential to enhance data quality by eliminating the possibility of noise and interference caused by wires (15–23). Considering the substantial amount of neural data to be collected, the most applicable technology for wireless neural recording is a battery- powered system with widespread availability of the associated hardware (18, 20–22). Batteries, known for their high energy density and operational stability, make them a promising choice for powering neural interface devices. However, current bulky and rigid battery configurations occupy over 90% of the device volume and more than 60% of its mass (16). To use these batteries on small animals, additional fixtures or suits are required to attach them to the head or back, hindering the free behavior of experimental animals(24, 25). Moreover, the risk of electrolyte leakage and overheating in conventional batteries poses a substantial obstacle to the formation of bio-integrated systems (26–29). Therefore, there is a strong need for batteries that (i) can be shaped to conform to nonplanar biological surfaces and (ii) consist of quasi–solid-state, biocompatible electrolytes to prevent leaks in wireless neural interfaces. In considering the entire neural interface system, various auxiliary electronic components are essential for the collection and processing of raw signals detected by neural probes. While numerous efforts have been made to enhance the long-term stability and signal quality of soft neural probes, the electronics responsible for wireless signal transmission and their electrical connections still typically use flat and rigid printed circuit boards (PCBs) made from solid, fragile materials (30, 31). These structural and material differences

 

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