The following is a quote from the linked article above:
"Sternberg's moral is that even though we don't know how free will emerges, we will some day, so we shouldn't throw moral responsibility out the window just yet."
Really? We don't?
Gee, that's funny. I could've sworn that we settled this whole debate ages ago when someone came up with the notion of "executive functions" of the brain. Ya know, that part of your brain they say isn't fully developed until you're in late adolescence. And I quote. . ."In the 1950s, the British psychologist Donald Broadbent drew a distinction between "automatic" and "controlled" processes (a distinction characterized more fully by Shiffrin and Schneider in 1977), and introduced the notion of selective attention, to which executive functions are closely allied" (Wikipedia. I know, I know) (However, for more info on the article in which Shiffrin and Schneider explore this more fully, see this reference: Shiffrin RM, Schneider W (March 1977). "Controlled and automatic human information processing: II: Perceptual learning, automatic attending, and a general theory". Psychological Review 84 (2): 127–90. ).
So what is selective attention? It is the capacity to maintain a behavioral or cognitive set in the face of distracting or competing stimuli. Therefore it incorporates the notion of "freedom from distractibility" . . . ya know, distractibility, as in distracting, random neurons that fire and tell us what to do beyond our control.
Oh, and in case you thought that the concept of "executive functions" was just a theory, I just happen to have a link to an article that demonstrates evidence of these executive brain centers being clearly identified: http://neurophilosophy.wordpress.com/2006/06/01/executive-brain-centres-identified/
So while young children and adolescents may not have an excuse because those areas of their brain are not yet fully formed, the rest of us with HEALTHY functioning brains (this excludes persons with Traumatic Brain Injuries (TBI) and other illnesses that affect brain functioning), seemingly have no excuse for a lack of moral responsibility.