Breakthrough in understanding of brains Immune cell involvement

on 04 November 2017
Your future, in your hands

With a consistency akin to that of soft butter, it's hard to think of the brain as being rigid; hard-wired but before Donald Hebb, that's exactly what most scientists believed it to be . . . 

Cells that fire together, wire together!

In fact, the brain is not only capable of being rewired, shaped or moulded to various differing states or viewpoints; it does so almost every minute. It is a constant state of flux; much of which we rarely are aware of. It is known that the brain grows in three ways, i.e. thru neuroplasticity, neurogenesis and developmentally, but how exactly it does this is not fully understood! Approximately 80 years ago neuroscience believed that the adult human brain was immutable, hardwired and incapable of large changes. Since then, minds (and brains) have changed. Of course, looking back it is more obvious to see they always have. Nowadays it is not only accepted that the adult brain is capable of change, but we now cherish the fact that it does so moment by moment!

Although the context of the research is in terms of studying neurodevelopmental disorders, it is clear that this is quite a normal function of the brain. It is, therefore, quite feasible to expand upon how this could relate to other methodologies. In that vein, change, in terms of brain function and development, is at the forefront of hypnosis and hypnotherapy and the degree to which hypnosis assists a client in making that change permanent is wholly dependent on any or all of the above forms of neural change taking place! Put simply, if your brain doesn’t change; neither will you!

By the very nature of how the brain works, at a cellular level, change is usually an incremental process, hence the saying, “practice (repetition) makes perfect.” The most general exception to that rule is changing as a consequence of a life-threatening experience. The activation of the fear (fight or flight) response is capable of making instantaneous and permanent changes in neural circuits (save that a reversal by therapeutic intervention is possible). Hypnosis effects change by virtue of altered states of mind, be it a heightened presence of subconscious processing or the absence of conscious processing! Neither of which require conscious awareness!

So, the value of this research, to all those who work within the realm of psychology, mind or spirit is immense. Scientifically it can enable the facilitation of better, more targeted, medications but there is also hope for its ability to enlighten us with new ways to tickle the imagination, to help one think more positively, to dream of better, more holistic outcomes etc. Of course, there is also a hidden (only if you can’t see it) benefit to the recipients of mental engineering (aka hypnosis), ordinary people who regularly make extraordinary personal achievements a regular and expected part of life’s journey; thru hypnosis!

The research
Microglia are cells that combat various brain diseases and injuries by swallowing foreign or disruptive objects and releasing molecules that activate repair mechanisms. Recent findings have suggested these brain cells are also active under normal conditions, where they can contribute to the maturation and sculpting of neuronal circuits. Researchers centred at the National Institute for Physiological Sciences (NIPS) have now revealed new mechanisms by which microglia sculpt neural circuits. They show that microglia directly contact neurons to induce the formation of new neuron projections that eventually will connect with other neurons and thereby increase and/or strengthen brain connectivity. These new findings could deepen understanding of how developmental disorders such as autism and schizophrenia may occur.

Early in development, neurons in the brain are particularly active in seeking out other neurons and forming connections with them. Cells called microglia, which were first identified via their protection of the brain against infection and decay, have recently also been shown to feature in brain development.

In a new study reported in Nature Communications, the researchers used a combination of fluorescent labelling of cells and molecules and imaging of particular regions of developing mouse brains to clarify how microglia influence the formation of neuronal circuits. They demonstrated direct contact between microglia and dendrites, which are the parts of neurons that enable them to communicate with each other. This contact induces the formation of filopodia -- thin structures that project out from the dendrites -- seek out the terminals of other neurons, and form synapses that enable neuronal communication. "We were able to image microglia contacting dendrites using in vivo multiphoton imaging of layer 2/3 pyramidal neurons. To our surprise, microglia -- dendrite contact caused a quite rapid appearance and growth of filopodia" lead author Akiko Miyamoto says. "We found that such contact was associated with accumulation of Ca2+ and actin and that blocking the microglia activity led to fewer functional synapses and less specific cortical circuits."

These findings could have important implications for a range of developmental diseases, as various studies have revealed associations between immune cells and neurodevelopmental disorders. "We know that some brain disorders are linked to abnormal numbers of synapses or changes in their shape and function. Disruption of the immune environment in the developing brain could be linked to some disorders," the corresponding author Junichi Nabekura says. "Our new findings of how microglia influence connectivity in the brain by creating filopodia that go on to produce synapses could give us new targets in the search for treatments for these conditions."

Story Source:
The above post is reprinted from materials provided by the National Institutes of Natural Sciences. Note: Content may be edited for style and length.

Journal Reference:
1. Akiko Miyamoto, Hiroaki Wake, Ayako Wendy Ishikawa, Kei Eto, Keisuke Shibata, Hideji Murakoshi, Shuichi Koizumi, Andrew J. Moorhouse, Yumiko Yoshimura, Junichi Nabekura. Microglia contact induces synapse formation in the developing somatosensory cortex. Nature Communications, 2016; 7: 12540 DOI: 10.1038/ncomms12540