Yes as Erik I too prefer poking the brain down to up or through the gill. It all depends on the anatomy of each fish: some have a skull so hard that it's difficult to make a hole in.
Fatman you're welcome I love to see japanese people on this board.
BUT: as Whopper said, get some infos about regulation and about fish before.
I tell you a brief story: today 12th of March 2008, it's my 20th spearfishing anniversary

. HURRA'!!!!

In facts it was March 12th 1988 when I speared my first fish. I was very happy and excited just like you, and bragged with the fish in triumph in a sort of parade in the town's main square.
BUT I didn't know what species of fish it was...so when an old fisherman in the square came by and told me it was a very rare, endangered and protected species, I felt very, very embarassed.
Fortunately, the old fisherman was just pulling my leg, he was making joke on me: the fish was not of any protected species. I felt relief about that. But then another fishermen told me that it was
the worst tasting fish of all. And unfortunately that was true....it was a small mediterranean reef fish whose latin/scientific name says it all:
turdus turdus....

After 20 years, I may say: the more you know and learn about the sea and about fish, the more you'll have fun and satisfaction from spearfishing!!! learn, learn and learn. We will be happy to be your buddies.
Friendly,
Spaghetti