Plastic Changes in the Brain Can Cause Tinnitus

Plastic Changes in the Brain Can Cause Tinnitus
Tinnitus is regarded to be a complex hyperactive disease, or rather tinnitus is a symptom with complex causes that indicate hyperactive neural activity. There is evidence that the neural activity that causes at least some forms of tinnitus is different from that evoked by sound. Earlier it was assumed that tinnitus was caused by increased firing rate of neurons occurring without sensory input. Recent studies indicate that other forms of abnormal activity somewhere in the nervous system, in particular how neural activity in populations of nerve cells are inter-related, may be the cause of some forms of tinnitus.

Evidence has been presented that abnormal synchrony and temporal coherence of the activity in populations of neurons may be the important factors for causing tinnitus [21, 22]. Activation of the nervous systems with temporal (periodic or non-periodic) signals, such as those occurring from sensory stimulation with sounds, creates coherence in the neural activity in a population of neurons because many neurons are activated by the same source. There are reasons to believe abnormal communications between nerve fibers or nerve cells (ephaptic transmission) may be involved in creating an abnormally high degree of temporal coherence of neural activity without any physical sensory input.

There is considerable evidence that activation of neural plasticity plays an important role in many forms of tinnitus. Activation of neural plasticity can alter the connectivity in the brain by unmasking dormant synapses. This is another factor that may be involved in some forms of tinnitus. There is also some evidence that the anatomically located regions activated in tinnitus are different from those that are activated by sound. There are indications that the neural activity that causes the awareness (conscious perception) of tinnitus is different from that which causes the affective (distress) reactions.

Such separation in processing of sounds that represent different kinds of information may be similar to the separation of different kinds of sensory signals described as stream segregation. The separation processing that leads to conscious perception and the processing that causes distress may indicate that these occur in different parts of the thalamus: the ventral part for processing of awareness and the medial and dorsal parts for the activity that causes affective symptoms. The dorsal and medial thalamus has subcortical connections to the amygdala. All these forms of changes in the function of the nervous system have few or no detectable morphological correlates.

Many aspects of tinnitus that have lasted a long time (e.g., more than 5 years) are different from tinnitus that has only lasted a short time (less than 5 years). Perhaps most important, tinnitus that has lasted a long time is more difficult to treat than tinnitus that has only lasted a short time [1].

 

Interesting.
Where does it come from? (source?)

 

Do not really know how useful this information is but maybe someone will find it interesting.

 

This is groundbreaking ! I will have to adapt this theory to the cure I am working on in my lab !

 

@RaZaH
yay! glad to be helpful!