I must have missed this episode, maybe after the whole “Spock’s Brain” mess, Kirk made him wear a flashing hemlet so they wouldn’t fall into the same trap again. It’s fun to think about Nimoy trying to do his lines with a straight face while wearing this.
AKA Brian Heiler author of "Rack Toys: Cheap, Crazed Playthings" and co-editor of "Toy-Ventures Magazine". Co-Host of the "Pod Stallions" podcast. Host of the Brick Mantooth Youtube channel, painter, designer, writer, mental health advocate, toy collector, Mego, and Mego Knock-Off enthusiast. I have large feet, ADHD and I live in Canada. Talk toys, not others. 
@brickmantooth
Official Tura Satana Action Figure Now Available
PlaidStallions Action Figure Archive
5 Awesome Things on eBay this week
Toy-Ventures Issue 12- Stretch Monster
Knock-Off Book
Man that looks like the Happy Happy Joy Joy helmet that Stimpy made for Ren in that one first season episide.
Maybe it gives Spock unlogical emotions…
I've seen pictures of people at Tea Party rallies wearing these.