جستجوی مقالات مرتبط با کلیدواژه "memory consolidation" در نشریات گروه "پزشکی"

Major depressive disorder is concomitant with cognitive deficits and executive function. This study aimed to determine the effectiveness therapeutic reconsolidation process model on executive functions, neuroplasticity, and schemas associated with major depressive disorder in veterans with over 25% of nerves. The study method was semi-experimental in the form of pre-test, post-test, and 45-day follow-up. Among the 50 nerves veterans above 25%, who had a history of being admitted to Niayesh Hospital in Tehran, 40 people were randomly assigned to the experimental and control groups and underwent intervention for 12 sessions of 90 minutes once a week for 3 months. The research tools were: Beck Depression Questionnaire (1996), Leahy Emotional Schemas (2002), Wisconsin Cards (2008), Stroop Color Test (1935), and Dennis Vanderwaal's Cognitive Flexibility Questionnaire (2010). Data were analyzed using 24spss software. The results of mixed variance analysis with repeated measurement showed that the training of the therapeutic reconsolidation process model was significantly effective on the executive functions, neuroplasticity and emotional schemas of the sample people. This result also lasted in the follow-up phase (P<0.05). the effective therapeutic reconsolidation process model was able to improve executive function, increase neuroplasticity, and compatible emotional schemas and maladaptive schemas in veterans over 25% of nerves by correcting traumatic memory and reducing depressive symptoms.

Sleep after a new sequence memory training can enhance the explicit memory in children. However, children’s sleep-dependent motor memory consolidation particularly in implicit complex sequence tasks is unclear. Therefore, this study aims to investigate the role of night-time sleep and wakefulness on children’s motor memory consolidation following an implicit complex task.

In the current study, 26 boys aged 9-12 years were randomly assigned in two groups of sleep and awake. Acquisition phase included 10 blocks of 96 trials. The sleep group performed initial training at 8 (±1) PM while the awake group performed it at 8 (±1) AM by using the dynamic arm movement task. The participants were not aware of the sequence order. After training, the children’s performance was tested after 12 hours.

The results of 2×2 Mixed ANOVA in the consolidation phase showed the significant main effect of block on response time (P=0.000) and prediction error (P=0.023). However, the interaction effect of block and group were not significant on response time (P=0.566) and prediction error (P=0.887). 

The sequence memory consolidation in children under an implicit complex task can be improved offline regardless of having sleep between training and test sessions. Hence, sleep is not necessary for offline enhancement of motor sequence skills. Passage of time is effective for improvement in dynamic arm movement task. Therefore, the role of sleep in offline learning of motor skills depends on the nature of the task used in training.

Memory consolidation is a set of processes that converts memory from an unstable state to a stable one. Various factors affect the consolidation of memory, including sleep and the type of exercise have an effect on consolidation. Given that little research on consolidation has used a motor task for the age group of children, the aim of thise study was to investigate the effect of sleep, type of exercise (Physical and Combine it whit observation of action) and posterior interference on consolidation processing based on stability and promotion of motor memory.

This research was a semi-experimental study with an pretest- posttest design. The statistical population included girls aged 10 to 12 years who had registered in volleyball in clubs in east Tehran in 2018. The sample included 62 novice girls in volleyball who were selected by available sampling method according to the inclusion and exclusion criteria. The experiments were divided into combined observation and physical exercise groups. The tools used in this study were, Landgrafe and Abetz child health questionnaire (1996), owens children's sleep habits questionnaire (2000), Aahperd Volleyball Serving Test (1969). Data were analyzed using combined factor analysis of variance with repeated measures and Benfferroni post hoc test.

The results of the analysis of variance-covariance with repeated measures showed that a night's sleep has a positive effect on stabilizing processing based on stability and promoting motor memory in children (F=15.40, P=0.001), but the type of exercise (F=0.18, P=0.67), (Physically or observational) and type of posterior interference (performing or observing the action) (F=0.48, P=0.489) have no significant effect on consolidation processing. Comparison of averages showed that physical practice is more stable and promotion motor memory than observation.

  Coaches and educators are recommended in addition to physical exercise, children can use observational exercise to process memory consolidation

Epilepsy is a very complex neurogenic disorder. Choronic epilepsy can affect memory and learning with neurochemical changes in different areas of the brain. Amitripyiline (AMT) is one of the the tricyclic antidepressants drugs that has antinociception effects. The aim of this study is evaluation of anticonvulsant and memory consolidationeffects of amitripyiline in male Wistar rats induced with Pentylentetrazole (PTZ).

In this experimental study 28male Wistar rats (200-250 g) were used and divided randomlyin 4 groups(n=7): control ( 0.5 ml salin normal), PTZ(60mg/kg), treatment 1 (PTZ + AMT10mg/kg  ) and treatment 2(PTZ + AMT20mg/kg). All injections were done interaperituneally.After administration of AMT the convulsive behaviors were observed and recorded. The passive avoidance, memory acquisitionand memory recovery tests were done. All data were analyzed with one way ANOVA and Tukey tests for evalution of differences between groups. 

The results of this study were showed thatthe delay in myoclonic movements in treated groups with AMT were increased compaired with PTZ group.The delay in memory recovery in PTZ group was reduced significantly compare with control group.

AMT is able to reduce the convulsion caused by PTZ injection and also the has positive effect on memory recoveryin rats .

A brief encounter with the cues associated with the drug leads to memory reconsolidation and disruption of drug memory by drug use can lead to memory update and reduced relapse.

This study aimed at determining the effectiveness of memory reconsolidation interference by propranolol on drug craving and its relationship with emotion in subjects with heroin use disorder.

This study was a quasi-experimental research with a pre-test-post-test and follow-up with a control group on 50 men (mean age 22 to 68 years) performed in Qom province addiction treatment camps in 2020. Data collection tools included demographic information questionnaire, structured diagnostic interview based on DSM.5, change readiness questionnaire, Bart impulsivity scale, computerized visual craving test, visual analog induction craving scale, and positive and negative emotion scale. Data were analyzed using SPSS software version 24 and multivariate analysis of variance tests with repeated measures and Pearson correlation at a significance level of less than P< 0.05. For the experimental group 10 minutes later from retrieval, propranolol (40 mg) was prescribed and the control group did not receive medication.

Repeated measures analysis of variance showed that interference in drug abuse memory reconsolidation by propranolol significantly reduced heroin induction craving in the experimental group as compared with the control group (P< 0.001). However, no statistically significant relationship was observed in pretest (P= 0.223, P= 0.08), posttest (P= 0.225, P= 0.186), and follow-up (P= 0.555, P= 0.018) between craving and positive or negative emotions.
Discussion and

The results of this study showed that neuroscience innovations can be used for the treatment of addiction disorders.

The purpose of the present study was to assess the effect of motor imagery training after exercise on motor memory consolidation in the elderly.

The statistical population of the study consisted of healthy men and women in Mashhad nursing homes 22 persons were randomly assigned to 2 groups: motor imagery and control (each group included 11 participants). Interventions in experimental groups include acquisition, retention after 24 hours, and retention after one week(retention 2). Motor memory task included performing a finger sequence, after which a complete simulation Supplement practice of motor imagery for the experimental group and a book study was performed for the control group for 15 minutes. Statistical analysis was an analysis of variance with repeated measures (to determine the effectiveness of motor imaging practice) as well as Bonferronichr('39')s post hoc test to identify significant improvement and covariance analysis test to compare two groups (motor imagery and control).

The results of this study showed that there is a significant difference between the two groups in retention 2 (F = 87.9, P = 0.005), and motor imagery protracted further gains in performance rather than the control group.

The results showed that the use of motor imagery practice as supplemental practice made significant improvements in different stages. Also, the results showed that motor imagery training is effective in improving motor memory consolidation in the elderly after one week.

After learning, memory must be stabilized before it becomes disrupted by subsequent learning. It is still unclear that how long it takes for new learnings to disruptprevious ones. Here in, the question of the present study was that learning a perceptual task would disrupt or interfere with the consolidation of the previously learned alternative motor sequence task, and what is the time interval between two tasks for maximum possible effect.
A number of 38 volunteers performed Serial Color Matching task for three blocks of 150 trials, then they randomly divided into three groups: 1) took part in perceptual task after one hour 2) took part in perceptual task after six hours 3) no extra task. All groups participated in retention test after 24 hours.
The results showed no significant differences between acquisition or retention of the previously learned motor task among groups.
These findings indicate rapid stabilization of implicit motor memory immediately after learning, in which time or learning a perceptual new task will not affect it.

Aims: In order to reach a better functioning in the athletic contests, the athletes needs to learn completely many and different motor skills. Therefore, to select properly an offline period between the motor skills are very important. The aim of this study was to investigate the effects of different offline periods on the consolidation periods based on stability in the implicit motor memory in the veteran and disabled athletes.
In the practical semi-experimental study, 45 veteran and disabled athletes with physical-motor disabilities, who were members of the athletic teams of Yazd Province in order to participate in the state contests and Olympiads, were studied in Yazd City in summer 2015. The subjects were selected via available sampling method. The subjects were randomly divided into three groups including 6-, 24-, and 72-hour offline period groups. The test was conducted at two stages including learning and retention using alternating serial reaction time task (ASRTT) and serial color matching task (SCMT). Data was analyzed using two-factor ANOVA with the repeated measures, one-way ANOVA, and Duncan and Bonferroni post-hoc test.
Findings: In the learning stage, the main effect of the group and the interaction effect of the group and the exercise package were not significant (p>0.05). Nevertheless, the main effect of the exercise package was significant (p=0.001). In the retention stage, the main effects of the exercise package (p=0.001) and group (p=0.048) and the interaction effect between them (p=0.001) were significant. A stability based consolidation process was seen in 24-, and 72-hour offline period groups. Nevertheless, there was a retroactive interference in 6-hour offline period group.
24- and 72-hour offline periods affect the stability based consolidation process in the implicit motor memory in veteran and disabled athletes.

Aims: Based on the studies, there are processes in resting interval following learning, through which the trained skills are transferred into the long-term memory structures. Such a process is called the consolidation process. There are conflicting results following studies about the effects of different off-line periods on the consolidation process in the motor memory. The aim of this study was to investigate the effects of different off-line periods on the enhance-based consolidation process in the implicit motor memory in veteran and disabled athletes.
Instrument & In the semi-experimental study, 45 male veteran and disabled athletes with physical motor disabilities were studied in Yazd in 2015.The subjects were selected via available sampling and randomly divided into three experimental groups with 6-, 24-, and 72-hour off-line periods. The test was done in two steps including learning and retention using alternating serial reaction time task (ASRTT). Data was analyzed using repeated measures two-factor ANOVA, one-way ANOVA, and Bonferroni’s post-hoc tests.
Findings: In the skill learning step, the major effect of the group and the interaction effect of the group and the training package were not significant. Nevertheless, the major effect of the training package was solely significant (p=0.002). In addition, in the retention step, the major effect of the group and the interaction effect of the training package and the group were not significant. Nevertheless, the major effect of the training package was significant (p=0.001). The functioning of three groups in the retention package was better than the fifth package in the learning step.
The off-line period and especially a 72-hour interval after the training and skill learning step can enhance the consolidation process in the implicit motor memory in the veteran and disabled athletes.

Extensive evidence documents arousal modulation of declarative memory in humans. However، little is known about the arousal modulation of implicit motor memory. The purpose of this study was to examine the effects of a post-acquisition acute exercise stress on implicit motor memory consolidation. Forty healthy subjects were randomly divided into stress (10 men and 10 woman) and non- stress (10 men and 10 woman) groups. Experiment consisted of two phases of acquisition and retention. Serial Color matching (SCM) task was used for this study. In acquisition period، all groups practiced the task for six blocks of 150 trials. Following، the stress group performed exercise on a treadmill until the moment of exhaustion while the non stress group did rest. In retention، all groups practiced the SCM task in one block. During the experiment the trends of saliva cortisol changes were measured. Acute exercise stress leads to a significant increase in salivary cortisol level. While the non-stress group did not show enhancement of SCRT learning across the 24 hours delay interval، the stress group showed substantial enhancement across the same time (P<0. 05). Our findings indicate that acute stress after acquisition can facilitate the implicit motor memory consolidation

The function of episodic memory is to recall what، where، and when something happened. Memory is prone to damage and change، and various factors can play a role in its changing and weakening. The purpose of this study was to determine the effect of emotion on the consolidation of episodic memory of female and male subjects. Therefore، in a study with an experimental design، from among Tabriz University students، 120 students (60 males and 60 females) were selected through cluster random sampling method in the academic year of 2010-2011. Then the subjects were provided with a list of words which were emotionally neutral and they were tested in terms of memory. After 5 minutes، the subjects were assigned equally and randomly into 3 groups. Each group was assigned a different task for 3 minutes i. e. watching positive videos، watching negative videos and resting. Then the three groups were again tested in terms of memory. The results of the study showed that only negative emotion significantly enhanced memory consolidation in females in some cases. However، neither positive nor negative emotions had any significant effects on source memory consolidation of both genders. The findings of the study indicate that the effects of emotion on episodic memory consolidation are not thorough and the emotion has different effects on males and females after they learn the patterns.

Evidence indicates that hipppocampus and activation of glucocorticoid receptors in this area are necessary for emotional learning and memory processes also some studies suggest that glucocorticoid’s effects probably involve with processes of protein synthysis in the hippocmapus. The aim of this study was to determine the role of intrahippocampal microinjections of anisomycin [(ANS) as a protein synthysis inhibitor)] on dexamethasone-induced modulation of memory consolidation in the passive avoidance learning (PAL) task in rats. In this study, 90 male Wistar rats (250–300 gr) were surgically implanted bilaterally with cannulae aimed at the dorsal hippocampus (DH) were trained in PAL task. In experiment 1. Dexamethasone (0.1, 0.5, 1 and 3 mg/kg IP) was injected immediately after training and vehicle injected into DH. In experiment 2. Anisomycin (0.5, 1 µg/µl/side) or vehicle were injected bilaterally into the DH followed immediately by IP injection of Dexamethasone (1 mg/kg) or vehicle. Two days after training, retention tests were done and step-through latency (STL) and total time spent in light chamber (TLC) of apparatus were recorded during 10 min and compared with controls. Data indicated that injection of Dexamethasone immediatly after training enhanced memory consolidation (P<0.01) and this effect was blocked by injection of ANS in to the DH (P<0.01). The findings above showed that glucocorticoids play on important role in consolidation of emotional learning and probably in processes of protein synthesis in the hippocampus may play an important role in mediating these effects.

Sexual hormones affect most of the cerebral functions as well as learning and memory. More investigations are required to clarify the effects of local administration of estradiol in the central nervous system. In this research we aimed at the effects of different doses of estradiol on memory consolidation in female gonadectomized rats.

Female Wistar rats (weighing 200-250 g, aged 3-4 months) were divided into 6 groups randomly (n=9). Five groups of animals were ovariectomized and implanted by cannulae in the CA1 region of hippocampus. Except sham group the other groups treated respectively with saline, sesame oil 0.5 μL and estradiol at the doses of 0.5, 1 and 2 μg / 0.5 μL sesame oil bilaterally in the CA1 region immediately after the passive avoidance training session. They were tested 10 min and 2 h after training.

Our results demonstrated that 0.5 μg estradiol had no significant effect on retention latency compared to sham group,1 μg estradiol treated group showed a significant increase (p<0.001) in retention latency compared to sham group while it decreased in the group treated with 2 μg dose of estradiol (p<0.05).

According to our findings, it seems that effects of estradiol in local administration are dose dependent and high doses of estradiol caused impairment of passive avoidance learning.

Piracetam is a nootropic compound, which acts as a nervous system enhancer. Different processes are involved in memory formation and various parameters are able to disturb it. Due to increase of exposure possibility to electromagnetic fields in recent years and the effects of theses fields on memory consolidation, this investigation designed to clear the relation between these parameters and memory consolidation. In this research eleven groups of male wistar rats (ten rats in each group) with a mean weight of 275±25 gr aging 3-4 months were studied. To evaluate the effects of electromagnetic field, four groups of rats were exposed to 5mT/50HZ electromagnetic field for 1,4,6 and 8 hours respectively immediately after training. In other six groups 250mg/kg or 500 mg/kg piracetam were administered orally one hour before training. They were also exposed to electromagnetic field for 4,6,8 hours respectively immediately after training,. Retrieval test was performed 24 hours later in all groups. 1 hour exposure on EMF had no meaningful effect on memory consolidation, however, in other three groups the electromagnetic fields impaired memory consolidation significantly compared to the control group (p<0.05). Piracetam administration with two mentioned doses significantly improved memory consolidation (p<0.05). Acute exposure to low intensity magnetic field can disturb memory consolidation and piracetam administration can prevent it.