Older news items (pre-2010) brought over from the old website
Perception affected by mood
An imaging study has revealed that when people were shown a composite image with a face surrounded by "place" images, such as a house, and asked to identify the gender of the face, those in whom a bad mood had been induced didn’t process the places in the background. However, those in a good mood took in both the focal and background images. These differences in perception were coupled with differences in activity in the parahippocampal place area. Increasing the amount of information is of course not necessarily a good thing, as it may result in more distraction.
[1054] Schmitz, T. W., De Rosa E., & Anderson A. K.
(2009). Opposing Influences of Affective State Valence on Visual Cortical Encoding.
J. Neurosci.. 29(22), 7199 - 7207.
http://www.eurekalert.org/pub_releases/2009-06/uot-pww060309.php
What we perceive is not what we sense
Perceiving a simple touch may depend as much on memory, attention, and expectation as on the stimulus itself. A study involving macaque monkeys has found that the monkeys’ perception of a touch (varied in intensity) was more closely correlated with activity in the medial premotor cortex (MPC), a region of the brain's frontal lobe known to be involved in making decisions about sensory information, than activity in the primary somatosensory cortex (which nevertheless accurately recorded the intensity of the sensation). MPC neurons began to fire before the stimulus even touched the monkeys' fingertips — presumably because the monkey was expecting the stimulus.
[263] de Lafuente, V., & Romo R.
(2005). Neuronal correlates of subjective sensory experience.
Nat Neurosci. 8(12), 1698 - 1703.
http://www.eurekalert.org/pub_releases/2005-11/hhmi-tsi110405.php
Varied sensory experience important in childhood
A new baby has far more connections between neurons than necessary; from birth to about age 12 the brain trims 50% of these unnecessary connections while at the same time building new ones through learning and sensory stimulation — in other words, tailoring the brain to its environment. A mouse study has found that without enough sensory stimulation, infant mice lose fewer connections — indicating that connections need to be lost in order for appropriate ones to grow. The findings support the idea that parents should try to expose their children to a variety of sensory experiences.
[479] Zuo, Y., Yang G., Kwon E., & Gan W-B.
(2005). Long-term sensory deprivation prevents dendritic spine loss in primary somatosensory cortex.
Nature. 436(7048), 261 - 265.
http://www.sciencentral.com/articles/view.htm3?article_id=218392607
Brain regions that process reality and illusion identified
Researchers have now identified the regions of the brain involved in processing what’s really going on, and what we think is going on. Macaque monkeys played a virtual reality video game in which the monkeys were tricked into thinking that they were tracing ellipses with their hands, although they actually were moving their hands in a circle. Monitoring of nerve cells revealed that the primary motor cortex represented the actual movement while the signals from cells in a neighboring area, called the ventral premotor cortex, were generating elliptical shapes. Knowing how the brain works to distinguish between action and perception will help efforts to build biomedical devices that can control artificial limbs, some day enabling the disabled to move a prosthetic arm or leg by thinking about it.
[1107] Schwartz, A. B., Moran D. W., & Reina A. G.
(2004). Differential Representation of Perception and Action in the Frontal Cortex.
Science. 303(5656), 380 - 383.
http://news-info.wustl.edu/tips/page/normal/652.html
http://www.eurekalert.org/pub_releases/2004-02/wuis-rpb020704.php
Memory different depending on whether information received via eyes or ears
Carnegie Mellon scientists using magnetic resonance imaging found quite different brain activity patterns for reading and listening to identical sentences. During reading, the right hemisphere was not as active as expected, suggesting a difference in the nature of comprehension experienced when reading versus listening. When listening, there was greater activation in a part of Broca's area associated with verbal working memory, suggesting that there is more semantic processing and working memory storage in listening comprehension than in reading. This should not be taken as evidence that comprehension is better in one or other of these situations, merely that it is different. "Listening to an audio book leaves a different set of memories than reading does. A newscast heard on the radio is processed differently from the same words read in a newspaper."
[2540] Michael, E. B., Keller T. A., Carpenter P. A., & Just M A.
(2001). fMRI investigation of sentence comprehension by eye and by ear: Modality fingerprints on cognitive processes.
Human Brain Mapping. 13(4), 239 - 252.
http://www.eurekalert.org/pub_releases/2001-08/cmu-tma081401.php
The chunking of our lives: the brain "sees" life in segments
We talk about "chunking" all the time in the context of memory. But the process of breaking information down into manageable bits occurs, it seems, right from perception. Magnetic resonance imaging reveals that when people watched movies of common, everyday, goal-directed activities (making the bed, doing the dishes, ironing a shirt), their brains automatically broke these continuous events into smaller segments. The study also identified a network of brain areas that is activated during the perception of boundaries between events. "The fact that changes in brain activity occurred during the passive viewing of movies indicates that this is how we normally perceive continuous events, as a series of segments rather than a dynamic flow of action."
Zacks, J.M., Braver, T.S., Sheridan, M.A., Donaldson, D.I., Snyder, A.Z., Ollinger, J.M., Buckner, R.L. & Raichle, M.E. 2001. Human brain activity time-locked to perceptual event boundaries. Nature Neuroscience, 4(6), 651-5.
http://www.eurekalert.org/pub_releases/2001-07/aaft-bp070201.php
Amygdala may be critical for allowing perception of emotionally significant events despite inattention
We choose what to pay attention to, what to remember. We give more weight to some things than others. Our perceptions and memories of events are influenced by our preconceptions, and by our moods. Researchers at Yale and New York University have recently published research indicating that the part of the brain known as the amygdala is responsible for the influence of emotion on perception. This builds on previous research showing that the amygdala is critically involved in computing the emotional significance of events. The amygdala is connected to those brain regions dealing with sensory experiences, and the theory that these connections allow the amygdala to influence early perceptual processing is supported by this research. Dr. Anderson suggests that “the amygdala appears to be critical for the emotional tuning of perceptual experience, allowing perception of emotionally significant events to occur despite inattention.”
[968] Anderson, A. K., & Phelps E. A.
(2001). Lesions of the human amygdala impair enhanced perception of emotionally salient events.
Nature. 411(6835), 305 - 309.
http://www.eurekalert.org/pub_releases/2001-05/NYU-Infr-1605101.php