The Effect of Negative and Positive Emotionality on Associative Memory: An fMRI Study

In general, emotion is known to enhance memory processes. However, the effect of emotion on associative memory and the underling neural mechanisms remains largely unexplored. In this study, we explored brain activation during an associative memory task that involved the encoding and retrieval of word and face pairs. The word and face pairs consisted of either negative or positive words with neutral faces. Significant hippocampal activation was observed during both encoding and retrieval, regardless of whether the word was negative or positive. Negative and positive emotionality differentially affected the hemodynamic responses to encoding and retrieval in the amygdala, with increased responses during encoding negative word and face pairs. Furthermore, activation of the amygdala during encoding of negative word and neutral face pairs was inversely correlated with subsequent memory retrieval. These findings suggest that activation of the amygdala induced by negative emotion during encoding may disrupt associative memory performance

〔資 料〕 閉経後女性の体脂肪蓄積，筋肉量および骨密度低下の抑制を 目的とした食事条件を提案するための基礎研究 ―自発運動可能な卵巣摘除メスラットの下肢骨格筋重量，大腿骨骨密度および 走行運動レベルに対する食餌アミノ酸添加の影響―

The present study aims to review whether dietary modifications will prevent body fat accumulation, muscle mass wasting and bone mineral density loss in postmenopausal women who incorporate physical exercise into daily life.9-week-old ovariectomized Wistar strain female rats were divided into four groups: CA-Ex, Gln-Ex, Leu-Ex and CitD-Ex. Depending on which group they were in, the rats were given a 20％ casein protein based experimental diet supplemented with nothing （control diet, CA-Ex）; 5％ of L-glutamine （Gln-Ex）; 5％ of L-leucine （Leu-Ex）; or 2.5％ of L-citrulline＋2.5％ of D-serine （CitD-Ex）, each 11 g per day for 10 weeks. All of these rats were housed in individual cage with a running wheel for 10 weeks. A sham operation was carried out on another group of rats （Sham） and were given the same diet as CA-Ex, the control diet.Results were as follows:1） Uterus weights of the ovariectomized rats, that is group CA-Ex, Gln-Ex, Leu-Ex and CitD-Ex, appeared to show lower values than that of the group Sham. 2） No significant differences were observed in a）changes in body weight, b）blood analyses, c）liver, kidney, uterus and muscle weights, and d）femoral-bone mineral density in groups Gln-Ex, Leu-Ex, and CitD-Ex as compared to the group CA-Ex.3） Relatively higher running activity was observed in group CitD-Ex than that of group CA-Ex. This observation suggests that increasing dietary L-citrulline plus D-serine in postmenopausal rats may lead to an increase in physical activity. Further research is needed to understand the physiological and nutritional significance of the unexpected results that dietary amino acid may accelerate the physical activity

Peripheral nerve regeneration following scaffold-free conduit transplant of autologous dermal fibroblasts: a non-randomised safety and feasibility trial

Abstract Background The use of Bio 3D nerve conduits is a promising approach for peripheral nerve reconstruction. This study aimed to assess their safety in three patients with peripheral nerve defects in their hands. Methods We describe a single institution, non-blinded, non-randomised control trial conducted at Kyoto University Hospital. Eligibility criteria included severed peripheral nerve injuries or a defect in the region distal to the wrist joint not caused by a congenital anomaly; a defect with a length of ≤20 mm in a nerve with a diameter ≤2 mm; failed results of sensory functional tests; ability to register in the protocol within 6 months from the day of injury; refusal of artificial nerve or autologous nerve transplantation; age 20–60 years; and willingness to participate and provide informed written consent. Six weeks before transplantation, skin was harvested, dermal fibroblasts were isolated and expanded, and Bio 3D nerve conduits were created using a Bio 3D printer. Bio 3D nerve conduits were transplanted into the patients’ nerve defects. The safety of Bio 3D nerve conduits in patients with a peripheral nerve injury in the distal part of the wrist joint were assessed over a 48-week period after transplantation. Results No adverse events related to the use of Bio 3D nerve conduits were observed in any patient, and all three patients completed the trial. Conclusions Bio 3D nerve conduits were successfully used for clinical nerve reconstruction without adverse events and are a possible treatment option for peripheral nerve injuries

Face-Word Association Paradigm.

<p>Subjects were asked to learn pairs of neutral face and emotional (positive or negative) words related to personality-trait by pressing a button. After the control task in which subjects were asked to press one of the target button, each face was shown with 3 words and subjects were asked to indicate, via button press, which word was previously paired with that face. (The picture of one of the authors was used in the Figure instead of that from the database of SOFTPIA JAPAN to protect the privacy of subjects participated in the database).</p

Correlation between amygdala activation and associative memory performance.

<p>A. shows the graph illustrates the inverse correlation between correct response rate of negative word - face pairs and the contrast estimates during encoding of negative word - face pairs in the region of interest shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0024862#pone-0024862-g002" target="_blank">Figure 2A</a>. B. shows the graph illustrates the positive correlation between correct response rate of positive word - face pairs and the contrast estimates during encoding of positive word - face pairs in the region of interest shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0024862#pone-0024862-g002" target="_blank">Fig. 2A</a>.</p

Correlation between activations in regions detected by one sample t-tests and associative memory performances.

<p><i>r</i>, correlation coefficiency; <i>p</i>, p-value;</p><p>*, <i>p</i><0.05.</p

Results of one sample t-test for positive word and neutral face pairs.

<p>BA, Brodmann area; L, Left; R, Right; Z, Z value of the peak activation within the cluster; Coordinates for the peak voxel are listed as MNI coordinates. p, corrected p value for whole brain or region of interest (^a bilateral hippocampus which include 1667 voxels or ^b bilateral amygdala which include 306 voxels); k_E, cluster size (voxels) difined by the same peak-level FWE thresholds and used for cluster level testing.</p