Sigh... so many more questions and very few if any answers. 
 None of these experiments or "trials" seem to make any scientific sense to me. (But then again, I'm reviewing books on the internet and not a scientist so maybe it's just me...) There has to be a much simpler and inexpensive way to map their brain patterns. The trials just seem elaborately superfluous. 
 Overall, the action was well paced and exciting. They definitely upped the ante in The Scorch Trials. 
 I just wished we paid a bit more attention to character development. We meet several new groups of people along the way (view spoiler)[ Jorge's crew, Blondie's crew, Group B, the full gone cranks... (hide spoiler)] but I don't feel like we ever got much more of a surface read to them. Basically Thomas meets them, tells his story, then escapes. (view spoiler)[ Seriously, that's the same formula for all of the meetings... except the cranks. That was mostly just running away. (hide spoiler)] Many of the Gladers just became one dimensional characters. Min Ho was a hot head, Newt was the peace maker, Wicked are still mad scientists, Jorge was a smart ass, etc... 
 Teresa and Aris were the wild cards. However, Aris seemed like he should be an important main character but was under utilized. I really don't know much of anything about him. (view spoiler)[ Apparently, their whole purpose was to betray Thomas. Which was heartbreaking by the way. Like Thomas, I'm not sure who can really be trusted anymore. (hide spoiler)] And another thing about Aris and Thomas's relationship (view spoiler)[ Aris and Thomas can talk telepathically. Every time Thomas got separated from his group (which happened a lot by the way...) I wondered why he didn't just call out to Aris telepathically. I mean he could have saved a lot of time and headaches if he did. He would have found out immediately where his friends were, if they were ok, or he could have called for help. I mean wasn't this so blatantly obvious for the readers that you just wanted to smack Thomas upside the head and just tell him to do it already! (hide spoiler)] 
 The characters I felt were interesting and grew were Brenda and Thomas. Brenda's situation, where she's aware she has a disease that's slowly driving her insane had some real depth to it. She didn't go into too many of the details regarding her life but the few times she did speak it had an impact and made me want to know more about her. (view spoiler)[And in the end where she was speaking inside of Thomas's head! Was that real!? What's that all about!? QUESTIONS!!!!??? (hide spoiler)] 
 I get the sense that Thomas, because of the trials, is no longer the person he used to be and he can never become that person again regardless of whether he gets his memories back or not. By the end of the book I feel like Thomas realizes that he has nothing left to loose and he finally... not "gives up" but more like "stops caring." He just stops feeling at all sometimes. Basically he's standing over the edge of cliff and doesn't particularly care if he falls off or not. It makes him dangerous. I'm interested to see how this plays out in the finale.