February 8, 2007
For a long time psychologists have devised methods to make people erroneous on a task. A well-known example is the Stroop effect, a demonstration of interference in the reaction time of a task. When a word such as blue, green, red, etc. is printed in a colour differing from the colour expressed by the word’s semantic meaning (e.g. the word “red” printed in blue ink), a delay occurs in the processing of the word’s colour, leading to slower test reaction times and an increase in mistakes.
The study of the neural correlates of the Stroop effect have revealed, among other correlates, an increased activation in the prefrontal cortex. But what happens if you discover that you have made a mistake and try to correct it? This kind of “error awareness” has now been documented in a recent study published in NeuroImage. We here bring the abstract and a poster.
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January 14, 2007
 When the neuro-talk falls on emotions, most start thinking about the amygdala. Little do we associate with that hind-brain structure we call the cerebellum. Although it is known that this structure is involved in more than movements, little is really known about it’s cognitive functions, let alone in emotions.
In an article by Turner et al. in Neuropsychologia, the function of the cerebellum in emotions is explored by comparing six patients with cerebellar injury and healthy subjects. By applying both behavioural and PET methods, the results demonstrate that cerebellum plays a role in both positive and negative emotions.
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January 3, 2007
December 31, 2006
Are conscious and nonconscious processes supported by overlapping brain regions? In a recent study, Slotnick and Schacter investigated whether activity, related to visual memory, in early visual regions (BA17 and BA18) is reflective of nonconscious processing. The results of their study suggest that early visual regions (BA17, BA18) are associated with nonconcsious memory, while late visual regions (BA19, BA37) are associated with conscious memory. Click through for abstract. Hubmed.
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December 30, 2006
 Which brain areas are involved in visuospatial consciousness? In a recent study by Babiloni and colleagues, subjects performed a visual perception task. Interestingly, these scientists found that visual-evoked potentials at parieto-occipital areas had the same peak latencies for cases of conscious, as well as unconscious, perception. These visual-evoked potentials were located to the occipital (BA 19) and parietal (BA 7) cortices. Source strength was significantly stronger in consciously, compared to unconsciously, perceived cases at about +300 ms poststimulus. Babiloni and colleagues concluded that these features of the observed parieto-occipital activation might be connected to visuospatial consciousness.
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December 22, 2006
 Brain stimulation provides an interesting tool to study the functions of a given area of the brain. In a study by Vignal et al. published in Brain, artificial stimulation or seizures in specific mesial temporal lobe structures were assessed both in terms of location and phenomenology.
Among the findings, the researchers found that “Forty-five per cent of dreamy states were evoked by stimulation of the amygdala, 37.5% by the hippocampus and 17.5% by the para-hippocampal gyrus.”
Furthermore, they found that their study “demonstrates the existence of large neural networks that produce recall of memories via activation of the hippocampus, amygdala and rhinal cortex.”
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December 21, 2006
 Steven Laureys and colleagues ask whether functional imaging methods such as fMRI and PET can be used to detect consciousness in individual patients. Recent studies have showed activation patterns in a vegetative patient that are comparable to helahty subjects. One pertinent question is therefore whether we can move from group studies towards individual scans. Here, Laureys et al. still have reservations, saying that “[published] data are insufficient to make recommendations for or against any of the neurorehabilitative treatments in vegetative state and minimally conscious state patients.”
How should functional imaging of patients with disorders of consciousness contribute to their clinical rehabilitation needs? Laureys S, Giacino JT, Schiff ND, Schabus M, Owen AM. 2006 Dec ; 19 (6): 520-527
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December 17, 2006
The more clear a stimulus is, the more distracting it can be. Or so you might think. In a recent Science publiation Tsushima et al. report that weak stimuli that are irrelevant to the task being performed—have
a greater impact than strong, easily noticeable distractors.
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October 4, 2006
 The second most read article in TICS (see previous headline) is a review (PDF) of studies from imaging genetics, the study of how genes make up our minds, as we have described here at SCR. Ahmad Hariri and Andrew Holmes reviews the evidence and discusses the implications of the genetic regulation of serotonin function on both brain function and behaviour in emotions.
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September 21, 2006
Neurobiologists have known that a novel environment sparks exploration and learning, but very little is known about whether the brain really prefers novelty as such. Rather, the major “novelty center” of the brain–called the substantia nigra/ventral tegmental area (SN/VTA)–might be activated by the unexpectedness of a stimulus, the emotional arousal it causes, or the need to respond behaviorally. The SN/VTA exerts a major influence on learning because it is functionally linked to both the hippocampus, which is the brain’s learning center, and the amygdala, the center for processing emotional information.
Now, researchers Nico Bunzeck and Emrah Düzel report studies with humans showing that the SN/VTA does respond to novelty as such and this novelty motivates the brain to explore, seeking a reward. The researchers of University College London and Otto von Guericke University reported their findings in the August 3, 2006, issue of Neuron, published by Cell Press.
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March 19, 2006
In a groundbreaking new study, researchers from the University of Michigan and Harvard University use cutting-edge brain-scanning technology to explore how different regions of the brain are activated when we think about certain qualities of brands and products. The study, forthcoming in the Journal of Consumer Research, is the first to use fMRI to assess consumer perceptions and has important implications for the use of metaphorical human-like traits in branding.
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February 20, 2006
We are readily able to distinguish movement made by ourselves and those by others. A recent study in Neuroimage by Balslev et al. demonstrate that the brain networks underlying these two experiences are indeed very similar. This means that a suggestion that recognition of visual feedback during active and passive movement relies on different brain areas is wrong.
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January 25, 2006
What happens when we suppress emotional thoughts or behaviour? In a study by Ohira and colleagues, it was shown that active suppression of emotions led to distinct patterns of activation. Areas activated in this PET study included the lateral and medial prefrontal and medial orbitofrontal cortices. Furthermore, the researchers found a tight correlation between the level of activation in the medial orbitofrontal cortex and skin conductance measures.
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December 27, 2005
What are the mechanisms behind attention, our ability to focus on some aspects or stimuli, and ignore others? Is it due to an inhibition of all other inputs than the attended one or by facilitating the one input and not the others? Or are both mechanisms at stake? A recent neuroimaging study contradicts a widespread belief that attention is due to inhibition, and instead lends support to theories suggesting that facilitation is the primary function in attention.
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December 26, 2005
A study by Nitschke and colleagues now demonstrate the neural correlates to the expectation of an aversive event. Experiencing as well as anticipating an aversive event involves specific structures such as the amygdala, insula cingulate cortex, prefrontal cortex and orbitofrontal cortex. An additional network involving smaller parts of the anterior cingulate, dorsolateral prefrontal cortex and orbitofrontal cortex was involved in the anticipation of an aversive event.
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What is the relationship and difference between Theory of Mind (ToM) and empathy? In the literature of social cognition, these terms have been used interchangeably. Völlm and colleagues demonstrate that there are indeed some differences in the brain systems underlyding these functions. While a certain extent of the network involved is similar for the two functions, they also have distinct systems. Empathy, for example, also involves the activation of well-known emotional structures such as the amygdala. In this way, functional brain imaging is used for mapping out functional units in the brain.
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December 21, 2005
Patients could suppress chronic pain by learning to control the activity of certain areas of their brains.
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December 12, 2005
A new discovery published in PNAS, from researchers at Dartmouth College and the Barrow Neurological Institute offers new insight into the localization of visual awareness of simple unattended targets in the visual system.
Open this post to read the full press release.
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December 11, 2005
In a recent paper in Nature Neuroscience, Morten Kringelbach summarizes the research on orbitofrontal cortex and its relation in organizing behaviour. In this paper, Kringelbach presents a new, integrated model of the functions of the orbitofrontal cortex.
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December 8, 2005
In a recent brain imaging study published in Neuron, Amedi and colleagues demonstrates that visual imagery deactivates areas in the auditory brain system and other “deeper” areas. This seems to suggest that normal visual perception requires a merging of information from many senses. In this sense, it seems that other sensory areas such as hearing can modulate the visual system. In visual imagery, this dynamic process is halted. Instead, visual imagery is the result of isolated processing in the visual cortices and a blocking of input from other sensory areas.
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