Friday, September 17, 2010

An artist's interpretation of evolution

Although somewhat of an unscientific account of the history of evolution, this is by far one of the most amazing stop motion films I have ever seen. Titled "BIG BANG BIG BOOM", the artist, BLU, utilized both paint and physical objects (lots of buildings) to recreate his own interpretation of the evolutionary process and what's in store for the future of Earth. Truly a brilliant work of epic proportions; it left me utterly speechless.

BIG BANG BIG BOOM - the new wall-painted animation by BLU from blu on Vimeo.


direction and animation by BLU
production and distribution by ARTSH.it
sountrack by ANDREA MARTIGNONI

Friday, September 10, 2010

The neuroscience of creativity and insight

Have you ever wondered what was going on in that noggin of yours when on that rare occasion you had an "aha!" moment or found yourself in a creative flow state, where even your screaming girlfriend couldn't snap you out of? Well Dietrich and Kanso over at the American University of Beirut seem to have mapped out the phenomena for us nicely. However, it's not quite as simple as you think.

In their review paper published in this month's Psychological Bulletin, they cover three broad categories related to insight and creativity. They are divergent thinking, artistic creativity, and insight. All studies reviewed used either electroencephalography, event-related potential, or neuroimaging.

The first category they looked at was divergent thinking, the thought process or method used to generate creative ideas by exploring many possible solutions. An example would be furiously brainstorming something interesting to write about on this darn blog. They found that numerous studies using the divergent thinking paradigm had one thing in common, that subjects exhibited some kind of diffuse prefrontal activation. Oddly enough, there was evidence for both increases and decreases in prefrontal activation depending on the study. They suggest that maybe different types of creativity were being tapped into.

Courtesy of Park Lab

Interestingly, people with schizophrenia show reduced prefrontal activation when performing divergent thinking tasks (Takeshi, 2010).

The next category the team covered was artistic creativity. In a particular series of studies, subjects were asked to mentally compose music, visualize abstract concepts, look at paintings, and imagine previously shown drawings; all under EEG monitoring. Activation of motor and temporalparietal regions were evident.

intense looking motor homunculus

The last category discussed was insight. Reviewing the literature they found that the anterior cingulate cortex, involved in early learning and problem solving,  was activated by insight problems and that the superior temporal gyrus, involved in the perception of facial expressions, was activated only when successful solutions to those insight problems were found. What is the sound of one hand clapping?!

The take home message Dietrich and Kanso emphasize is that no single brain area, nor a particular hemisphere for that matter, is involved in creativity or insight (contrary to popular belief). The next time your hipster artist friends tell you they're more "right brain" than anything else you can politely correct them by explaining...

I highly recommend you check out the article as there is a lot I did not cover.

References:


Dietrich A, & Kanso R (2010). A review of EEG, ERP, and neuroimaging studies of creativity and insight. Psychological bulletin, 136 (5), 822-48 PMID: 20804237

Takeshi K, Nemoto T, Fumoto M, Arita H, & Mizuno M (2010). Reduced prefrontal cortex activation during divergent thinking in schizophrenia: A multi-channel NIRS study. Progress in neuro-psychopharmacology & biological psychiatry PMID: 20673784

This post was chosen as an Editor's Selection for ResearchBlogging.org

Tuesday, September 7, 2010

Is recognition without awareness possible?

It seems common knowledge in the world of neuroscience that episodic memories are formed through conscious awareness. However, a couple of years ago Voss and Paller found that this may not necessarily be the case. They had subjects perform a forced choice recognition task using kaleidoscope images (for novelty's sake). Interestingly, accuracy was highest when subjects reported guessing, thus indicating little awareness that the studied images had been seen before. "This indicates that episodic memory processing was unhelpful, and suggests that subjects responded instead based on pure visual fluency."

In a second study, the team discovered that subjects performed better on tests of episodic memory when they paid divided attention rather than full attention, further validating their findings. In their 2009 paper they concluded by stating that "our findings add weight to the proposal that nonhuman animals utilize visual fluency without episodic memory when performing tasks intended to probe episodic memory."

However, contrary results have recently been published in this month's Learning & Memory. In a replication study Jeneson, Kirwan, and Squire, found that recognition was better when subjects paid full attention to the visual stimuli compared to paying partial attention. In addition, recognition was better when subjects reported some level of confidence as compared to a guess.

Vass and Paller responded to the disconfirming study by running a further study of their own. To resolve the apparent discrepancy they added a simple manipulation to encourage either guessing or confident responding. They found that encouraging guessing increased prevalence and accuracy of guesses relative to the confident responding condition. The authors suggest that both the prevalence and accuracy of guessing can be influenced by whether subjects adopt guessing-friendly strategies. So the lesson here is...guess away!

References:

Voss JL, & Paller KA (2009). Recognition without awareness in humans and its implications for animal models of episodic memory. Communicative & integrative biology, 2 (3), 203-4 PMID: 19641728

Jeneson A, Kirwan CB, & Squire LR (2010). Recognition without awareness: An elusive phenomenon. Learning & memory (Cold Spring Harbor, N.Y.), 17 (9), 454-9 PMID: 20810620

Voss JL, & Paller KA (2010). What makes recognition without awareness appear to be elusive? Strategic factors that influence the accuracy of guesses. Learning & memory (Cold Spring Harbor, N.Y.), 17 (9), 460-8 PMID: 20810621