The memory disorder is triggered by the electromagnetic wave manipulation, which is not just for the short-term but the long-term as well. There are two types of the dysmnesia symptom, one of which is unable to retrieve the memory as a result of the total malfunction of the brain. Another is that the long-term memory is lost from the brain.
In the most of cases, the memory is impaired temporarily, not fundamentally deleted from the brain. The radiowave control restricts the synaptic connection to the long-term memory, which appears as the temporal retrograde amnesia. However, the memory is occasionally lost permanently from its manipulation. In this case, the long-term memory is lost, but it is more like an issue of the connection, hence you can recreate the same memory easily, even though you forget the previous one. It implies it is an issue of the synaptic connection, not the memory cell itself.
When the brain is malfunctioned, you cannot retrieve the long-term memory with a headache which is a similar symptom that you have suffered from the short-term memory loss. On the other hand, if your access is restricted to the long-term memory, there is no headache, but just you cannot retrieve what it is. It is purely an issue of the access, therefore you can recall the memory when looking at the memos as an external memory.
This headache might be the same as the CPU is malfunctioned. When the CPU is too busy, the PC is frozen, which halts any functions of the computer. In that case, you cannot retrieve any memories for both long-term and short-term. In the brain case, it is likely driven by the ischemia.
On the other hand, the long-term memory also cannot be recalled when the hard disk is malfunctioned. In this computer case, the memory itself is still out there on the disk, but the system cannot read it with some disorders. This is analogous to the retrograde amnesia that you cannot have an appropriate access to the memory, hence you cannot retrieve the memory.
When you play the piano, you suddenly lose your long-term memory due to the electromagnetic wave control. It is necessary to recreate the memory, though its task is easier than initial, which means your memory is still in the cell and you should recover the synaptic connection lost from to the brainwave manipulation.
It might damage the connection taken place at the exact same time when irradiated. However, the precise phenomenon is not elucidated yet. It is affected by the specific frequency pattern, but that frequency might be different from the brainwave, whose possibility is even not denied yet.
There is another malfunction that the whole brain loses the concentration with feeling a heat on the face, which is basically similar to the stupefaction. It is not the memory disorder, but your behavior is restricted due to its dysfunction.
This feeling is felt on the face, but it is just a symbol that you are likely to feel it in the whole head. Or, the heat is actually generated deep inside the brain, such as midbrain or hypothalamus, which is why it is felt on the face. All I know is that this symptom is created by the brainwave control to trigger the chemical change inside the brain with the total dysfunction.