Developing Intelligence

Archives for May, 2008

In this poster, Bastos, Mullen and colleagues show that they can analyze electrical oscillations on the scalp of human subjects and predict how quickly they will respond in a simple target detection task. They do this by an interesting method known as the Steady State Visual Evoked Potential (SSVEP), otherwise known as “frequency tagging”: the…

The organization of the human prefrontal cortex (PFC) is a lasting mystery in cognitive neuroscience, but not for lack of answers – the issue is deciding among them, since all seem to characterize prefrontal function in very different but apparently equally-valid ways. If this mystery were resolved, it could revolutionize cognitive neuroscience and neuropsychology as…

“It has attained a certain mystique in the physical and biological sciences because it manages to be both rare and ubiquitous. Examples […] are found in quasar luminosity, tide and river height, traffic flow, and human heartbeat…” (Gilden & Hannock) Since the mid-90s, a small group of cognitive psychologists have turned their attention to variability…

New research from Wharton and the Carlson School shows that a methodologically-appealing measure of impulsivity – hyperbolic discounting rate – may actually reflect a systematic “skew” in the way people perceive time. Previous work has shown that people tend to decreasingly discount the usefulness or appeal of a reward with increasing delays; that is, a…

In 2001, Yamamoto and Kitazawa showed that the perception of temporal order can be reversed when subjects cross their hands. Subjects closed their eyes and had their hands mechanically touched in quick succession (with stimuli separated in time by a variable amount – from 1500 ms to 0 ms). Subjects were asked to raise the…

Your ability to control thought and behavior relative to your peers – a set of capacities known as “executive functions” – is almost entirely genetic in origin, according to a newly in-press paper from Friedman et al. Over 560 twins completed tests to measure fundamental components of these executive functions, and the results were analyzed…

Time pervades our understanding of the world – we use it to coordinate our movements, to perceive motion, to plan our behaviors, and perhaps even to understand causality. But it is an under-appreciated factor in cognition. Even in the domain of the well-understood visual system, few realize that neurons in visual cortex are tuned not…

Our ability to suppress unwanted thoughts and behaviors is thought to be related to a process known as “inhibition,” whereby ventrolateral regions of prefrontal cortex (vlPFC) actively suppress inappropriate representations. A 2001 study by Sakagami et al. recorded firing data from neurons in the vlPFC to determine the exact mechanism by which this might occur.

Does the resolution or precision of human memory change with its available capacity? In other words, can you remember fewer items with greater precision than you can remember more items? Contradicting intuition, a new paper from yesterday’s issue of Nature shows that all items are stored in memory with equal resolution, regardless of the number…

Complex cognition can be predicted by remarkably simple tasks. For example, the speed with which you choose one of two possible responses can reliably predict IQ. Some theories propose that this relationship is due to differences in something called “processing speed,” but more recent work has shown the effect is really due to the slowness…