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Anticipation is informed by experience. Having focused on action effects in the past will lead to differences when the focus is now on the effector. Boules-type throwing movements were presented as point-light displays of shoulder and arm-markers. Activation in motor-related areas measured with functional magnetic resonance imaging was compared between two tasks: Task A anticipating action effects and Task B judging the velocity of the hand marker. One group of participants performed a session of Task A followed by a session of Task B; the other group started with Task B followed by Task A. The group starting with Task A exhibited higher brain activation during Task A bilaterally in intraparietal areas and in right hemispheric frontal and premotor areas. These areas are known to be involved in effect estimation and action simulation. The second group showed higher activation during Task B in premotor cortex and human intraparietal area 3 of the right hemisphere. The results suggest that the instruction to focus on anticipating action effects facilitates the recruitment of core components of the simulation network during anticipation and when effect anticipation is not the primary intention.

This study investigated whether activation within areas belonging to the action observation and imitation network reveals a linear relation to the subsequent accuracy of imitating a bimanual rhythmic movement measured via a motion capturing system. 20 participants were scanned with functional magnetic resonance imaging (fMRI) when asked to imitate observed bimanual movements either concurrently versus with a delay (2s) or simply to observe the movements without imitation. Results showed that action observation relates to activation within classic mirror-related areas. Activation patterns were more widespread when participants were asked to imitate the movement. During observation with concurrent imitation, activation in the left inferior parietal lobe (IPL) was associated negatively with imitation accuracy. During observation in the delayed imitation condition, higher subsequent imitation accuracy was coupled with higher activation in the right superior parietal lobe (SPL) and the left parietal operculum (POp). During the delayed imitation itself, a negative association between imitation accuracy and brain activation was revealed in the right ventral premotor cortex (vPMC). We conclude that the IPL is involved in online comparison and visuospatial attention processes during imitation, the SPL provides a kinesthetic blueprint during movement observation, the POp preserves body identity, and the vPMC recruits motor representations--especially when no concurrent visual guidance is possible., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Much recent research has shown an association between mood disorders and an altered emotion perception. However, these studies were conducted mainly with stimuli such as faces. This is the first study to examine possible differences in how people with major depressive disorder (MDD) and healthy controls perceive emotions expressed via body movements. Thirty patients with MDD and thirty healthy controls observed the video scenes of human interactions conveyed by point-light displays (PLDs). They rated the depicted emotions and judged their confidence in their rating. Results showed that patients with MDD rated the depicted interactions more negatively than healthy controls. They also rated interactions with negative emotionality as being more intense and were more confident in their ratings. It is concluded that patients with MDD exhibit an altered emotion perception compared to healthy controls when rating emotions expressed via body movements depicted in PLDs.

One central issue in social cognitive neuroscience is that perceiving emotions in others relates to activating the same emotion in oneself. In this study we sought to examine how the ability to perceive own emotions assessed with the Toronto Alexithymia Scale related to both the ability to perceive emotions depicted in point-light displays and the confidence in these perceptions. Participants observed video scenes of human interactions, rated the depicted valence, and judged their confidence in this rating. Results showed that people with higher alexithymia scores were significantly less confident about their decisions, but did not differ from people with lower alexithymia scores in the valence of their ratings. Furthermore, no modulating effect of social context on the effect of higher alexithymia scores was found. It is concluded that the used stimuli are fit to investigate the kinematic aspect of emotion perception and possibly separate people with high and low alexithymia scores via confidence differences. However, a general difference in emotion perception was not detected in the present setting.

TEM and SEM application demonstrated that the shift from chondrification to ossification in the developing murine centra from day 15 to day 18 of gestational age is marked by typical structural variations of the extracellular matrix (ECM). During day 15 GA, typical matrix vesicles with crystalline contents appeared, as followed by single and fusing pleomorphic aggregates of a more regular crystalline structure. During days 17/18 GA, these structures disappeared, and the ECM now exhibited a network of collagen fibrils that had been less conspicuous before. During the time period studied, the ECM switched from a more acid (proteoglycans) to a rather neutral (glycoproteins) milieu.

This study investigates, on a circadian basis, the variation in blood serotonin for a group of 64 healthy persons (volunteers of a Bundeswehr-Ausbildungskompanie); a pronounced circadian rhythm of 5-HT has been found. The variation in daily absolute levels is influenced by novelty stress; by this we refer to the stress resulting from initial contact between the person sampling blood and the patient. Obviously this diminishes as blood is repeatedly withdrawn from the same individual. Exposure to this situation results in an overall decrease in serotonin levels and a modification of the circadian pattern.

This study evaluates the ethanol toxicity for fetal development at different circadian stages. Pregnant mice were given a single intraperitoneal ethanol injection on day 7, 8, or 10 of gestation at one of four circadian stages (0700, 1300, 1900, or 0100 hr). The dams were killed on the day before term (day 18). Prenatal exposure to ethanol resulted in an increased number of resorptions, reduced fetal body weight, and produced an increased incidence of external alterations. The severity of damage was related to the dose, the period of gestation, and particularly to the circadian stage at the time of treatment. Ethanol had the greatest effect on the embryo of a mouse when administered at the mid-dark span. Consequently exposure to a single dose of ethanol at one time or another along the 24-hr time scale during organogenesis has important implications for the substantially increased risk.

At different times of the day activities of hydrolytic (alkaline and acid phosphatase, esterase) and oxydative (succinodehydrogenase, cytochromoxidase, monoaminoxidase) enzymes were studied in the epithelium of the upper part of the jejunum in the adult female mouse and the adult laying chicken. In both species the activities of the intestinal enzymes showed marked circadian variations with respect to their activity and distribution pattern. The variations did not principally differ in both species. The species' differences were mainly expressed by phase shifts of about 12 h in the occurrence of maximal and minimal activities according to the different phases of the locomotor activity of the mainly night-active mice and day-active chickens.

Circadian influences on growth and development in response to ethanol were studied in mice. On gestational day 10, pregnant animals received a single intraperitoneal injection of ethanol with the following dose levels: 1.0, 2.5 or 4.0 g/kg at one of four circadian phases (0700, 1300, 1900 or 0100 hr). 48 hrs after injection the embryonic weight and length, protein and DNA content and placental weight and protein were determined. Ethanol-related intrauterine growth retardation were shown to be dose- and circadian phase-dependent, the greatest susceptibility being seen during the dark phase. The variations observed are discussed with regard to changes in drug metabolism and tissue sensitivity.

Pregnant mice were injected once with cyclophosphamide (20 mg/kg) or Th-R (N-mustard, 2 mg/kg) at one of four different day-times (07.00, 13.00, 19.00, 01.00) on the 12th day of gestation. In a therapeutic dose both alkylating neoplastic agents induced teratogenic effects relative to the maternal circadian cycle. The highest incidence of malformations due to maternal treatment with cyclophosphamide was found to be associated with the dark to light transition (07.00), whereas the lowest occurred at 01.00. In contrast, the teratogenic action of Th-R was strongest at the onset of darkness (19.00) and lowest at 07.00. The mean embryotoxicity of both compounds was subjected to seasonal modifications, being highest during spring and summer and lowest during winter. - The observations indicate that for the evaluation of the teratogenic potentialities of drugs, rhythms cannot be neglected.

Pregnant mice were treated intraperitoneally with 5-fluorouracil in a single dose of 30 mg/kg once on gestation day 11 at one of four selected times along the 24-hr time scale. All animals were kept under a lighting regimen of 12 hr (0600-1800) alternating with 12 hr of darkness. They were injected at the same circadian phase as they were mated. The developmental age of all fetuses was 264 +/- 1 hr at the time of injection. Fetuses collected on day 18 showed a circadian variation in teratogenic susceptibility to 5-fluorouracil. The lethal and teratogenic risk posed by the drug were highest among animals treated at the mid-light period until the onset of darkness.

Pregnant mice were treated intramuscularly with dexamethasone in a single dose of 10 or 50 mg/kg once on day 13 of pregnancy at one of 4 fixed times. On day 18 palate condition of live fetuses and the number of resorptions were recorded and the relation of the incidence of palatal defect and serum corticosterone level was examined. The results suggest that there are different susceptibilities to teratogen-induced cleft palate during a 24-h period. The frequency of cleft palate was increased among term fetuses when there was a drop in the endogenous glucocorticoid of the dams.