Early phase in human brain development

Resting-state networks in the infant brain.
Peter Fransson, Beatrice Skiold, Sandra Horsch, Anders Nordell, Mats Blennow, Hugo Lagercrant and Ulrika Åden.
PNAS, September 25,2007,vol.104, no.39, 15531–15536

Background: In the absence of any overt task performance, it has been shown that spontaneous, intrinsic brain activity is expressed as systemwide, resting-state networks in the adult brain. However, the route to adult patterns of resting-state activity through neuronal development in the human brain is currently unknown.

Methods: 12 infants were scanned at term-equivalent age during sleep for 10 min. The total scanning time was 45–50 min. Functional MRI was used to map patterns of resting-state activity in infants during sleep. Physiologically relevant resting-state networks across subjects were extracted by using ICA.

Results: They found five unique resting-states networks in the infant brain that encompassed the primary visual cortex, bilateral sensorimotor areas, bilateral auditory cortex, a network including the precuneus area, lateral parietal cortex, and the cerebellum as well as an anterior network that incorporated the medial and dorsolateral prefrontal cortex.

Conclusions: The results suggest that resting-state networks driven by spontaneous signal fluctuations are present already in the infant brain. The potential link
between the emergence of behavior and patterns of resting-state activity in the infant brain is discussed.

Authorship Dilemma - Scientific Misconduct

Physicists do it by the hundred; scientists do it in groups; fiction writers mostly alone. And researchers? Rarely now do they write papers alone, and the number of authors on papers is ever increasing. However, the puzzling question here is who is the first author ?

The operative word here is "boss". It's his/her final decision. People get "cheated" out of first authorship all the time.

I agree to some extent when others that say it should be your boss's decision, although I think it is pretty lousy and unfortunately, we don't have any guidelines to go by. The lab politics and professional courtesy should not affect rewarding hard or tedious work which essentially should be looked at in the authorship decision. I don't think it's fine as long as your boss/PI spells out the exact contributions of each author in his/her letter of recommendation when it comes time for you to apply for jobs. Since according to me that seems like a small consolation although atleast it ensures you get appropriate credit with the people who matter most (especially potential future employers).

In most cases first authorship should be given to the person who did the most work, with the various types of work weighted by their values. Some work is more valuable than other. Generally, designing the research and writing the manuscript are considered more valuable than doing the statistical analysis, which is considered more valuable than collecting the data.

In this era of team-driven science I think the whole importance to the concept of first author is absurd. In fact, some journals require a final statement about the contribution of each author. I guess the tentative fix is that each author's contributions should be listed or acknowledged upon submission in every journal.

Whether or not scientific societies develop authorship policies of their own, they should undertake vigorous educational efforts to keep their new members adequately informed about the importance of authorship practices in ethical scientific research and publication. Since, it's all about research integrity.

References to articles on this topic
- APA Monitor Article, "The Authorship Dilemma," Dec., 1998
- Fine and Kurdek, American Psychologist, 48:1141-1147
- Costa and Gatz, Psychological Science, 3:354-357.
- Louw and Fouché, South African Journal of Psychology, 29:145-148.
- http://grants.nih.gov/grants/policy/

Americans are Trading Sleep for Work and Gridlock

For many people, the American dream means owning a big house with an even bigger yard and a couple of attractive cars in the driveway. But what sacrifices are we willing to make in order to realize these super-sized dreams? A new study finds that sleep may be one of them: working long hours and being stuck in traffic appears to be keeping many Americans from their sleep. The study was based on the results of a federal telephone time-use survey of more than 47,000 Americans conducted from 2003 to 2005. The results showed that the amount of time spent working is the most important factor in determining how much Americans sleep. Time spent traveling, including those frustrating hours in gridlock, comes in second place.

American Time Use Survey: Sleep Time and Its Relationship to Waking Activities
Mathias Basner, MD, MSc; Kenneth M. Fomberstein; Farid M. Razavi; Siobhan Banks,PhD; Jeffrey H. William; Roger R. Rosa, PhD; David F. Dinges, PhD

To gain some insight into how various behavioral (lifestyle) factors influence sleep duration, by investigation of the relationship of sleep time to waking activities using the American Time Use Survey (ATUS).

Methods: Cross-sectional data from ATUS, an annual telephone survey of a population sample of US citizens who are interviewed regarding how they spent their time during a 24-hour period between 04:00 on the previous day and 04:00 on the interview day.

Results: Adjusted multiple linear regression models showed that the largest reciprocal relationship to sleep was found for work time, followed by travel time, which included commute time. Only shorter than average sleepers (<7.5 h) spent more time socializing, relaxing, and engaging in leisure activities, while both short (<5.5 h) and long sleepers (≥8.5 h) watched more TV than the average sleeper. The extent to which sleep time was exchanged for waking activities was also shown to depend on age and gender. Sleep time was minimal while work time was maximal in the age group 45-54 yr, and sleep time increased both with lower and higher age.

Conclusions: Work time, travel time, and time for socializing, relaxing, and leisure are the primary activities reciprocally related to sleep time among Americans. These activities may be confounding the frequently observed association between short and long sleep on one hand and morbidity and mortality on the other hand and should be controlled for in future studies.

Influence of Emotional Expression on Memory Recognition Bias

Influence of Emotional Expression on Memory Recognition Bias: A Functional Magnetic
Resonance Imaging Study
Karine Sergerie, Martin Lepage, and Jorge L. Armony
Biol Psychiatry. 2007 May 31

Background: Most studies of the influence of emotion on memory performance have focused on accuracy. However, there is evidence that emotion can influence other aspects of memory, in particular response bias (overall tendency to classify items as new or old regardless of the accuracy of the response). Here, they investigate the behavioral and neural-related modulation of response bias by emotion.

Methods: Nineteen healthy individuals performed a recognition memory task on faces with happy, sad, and neutral expressions while undergoing functional magnetic resonance imaging (fMRI).

Results: A familiarity (tendency to say “old”) and novelty (tendency to say “new”) bias for sad and happy faces, respectively. Novelty response bias was associated with amygdala and prefrontal cortex activity, whereas familiarity bias correlated with superior temporal gyrus activation.

Conclusions: The results show that emotional expressions can have an influence on memory beyond simple accuracy and that this effect is in part mediated by the amygdala, a region previously implicated in emotional perception and memory. Important clinical relevance since it explains some of the inconsistencies in the literature regarding emotional memory deficits in psychiatric populations.

Unconscious Emotion

Unconscious Emotion
Piotr Winkielman and Kent C. Berridge
University of California, San Diego, and University of Michigan
Current Directions in Psych Science

Conscious feelings have traditionally been viewed as
a central and necessary ingredient of emotion. Here we argue
that emotion also can be genuinely unconscious. We describe
evidence that positive and negative reactions can be elicited
subliminally and remain inaccessible to introspection. Despite
the absence of subjective feelings in such cases, subliminally
induced affective reactions still influence people’s preference
judgments and even the amount of beverage they consume. This
evidence is consistent with evolutionary considerations suggesting
that systems underlying basic affective reactions originated
prior to systems for conscious awareness. The idea of
unconscious emotion is also supported by evidence from affective
neuroscience indicating that subcortical brain systems underlie
basic ‘‘liking’’ reactions. More research is needed to clarify the
relations and differences between conscious and unconscious
emotion, and their underlying mechanisms. However, even under
the current state of knowledge, it appears that processes
underlying conscious feelings can become decoupled from processes
underlying emotional reactions, resulting in genuinely
unconscious emotion.

Facial Expressions of Emotion Influence Memory

Facial Expressions of Emotion Influence Memory for Facial Identity in an Automatic Way
Arnaud D’Argembeau
University of Liege, Belgium
Martial Van der Linden
University of Geneva, Switzerland, and University of Liege, Belgium
Emotion. 2007 Aug;7(3):507-15.

Background: Previous studies indicate that the encoding of new facial identities in memory is influenced by the type of expression displayed by the faces. In the current study, the authors investigated whether or not this influence requires attention to be explicitly directed toward the affective meaning of facial expressions.

Methods: The experiment consisted of a 3 (encoding condition: expression, intelligence,nose size) x 2 (facial expression: happy, angry) mixed model design with encoding condition as a between-participants factor and expression as a within-participants factor.

Results: In a first experiment, the authors found that facial identity was better recognized when the faces were initially encountered with a happy rather than an angry expression, even when attention was oriented toward facial features other than expression. Using the Remember/Know/Guess paradigm in a second experiment, the authors found that the influence of facial expressions on the conscious recollection of facial identity was even more pronounced when participants' attention was not directed toward expressions.

Conclusions: It is suggested that the affective meaning of facial expressions automatically modulates the encoding of facial identity in memory.

Emotional faces predominate in binocular rivalry

Here Is Looking at You: Emotional Faces Predominate in Binocular Rivalry
Georg W. Alpers and Antje B. M. Gerdes
University of Wurzburg
Emotion. 2007 Aug;7(3):495-506.

Background: Two incompatible pictures compete for perceptual dominance when they are presented to one eye each. This so-called binocular rivalry results in an alternation of dominant and suppressed percepts. In accordance with current theories of emotion processing, the authors' previous research has suggested that emotionally arousing pictures predominate in this perceptual process.

Methods: Three experiments were run with pictures of emotional facial expressions that are known to induce emotions while being well controlled in terms of physical characteristics. In Experiment 1, photographs of emotional and neutral facial expressions were presented of the same actor to minimize physical differences. In Experiment 2, schematic emotional expressions were presented to further eliminate low-level differences. In Experiment 3, a probe-detection task was conducted to control for possible response-biases.

Results: These data clearly demonstrate that emotional facial expressions predominate over neutral expressions; they are more often the first percept and they are perceived for longer durations. This is not caused by physical stimulus properties or by response-biases.

Conclusions: This novel approach supports that emotionally significant visual stimuli are preferentially perceived.