Basic and Clinical Neuroscience最新文献

Introduction: Consumers' prior experiences form an episodic memory that largely influences their decision-making process. This episodic memory is mainly linked to cognitive and emotional perception and we know that brand image influences our cognitive and emotional perception. Nevertheless, it has not been well described how autobiographical memories of brand images differ from other types of images.

Methods: In this study, we hypothesized that brand pictures have a higher chance to create false memories as compared to neutral ones.

Results: We investigated this hypothesis using the Deese-Roediger-McDermott paradigm with lists of brand pictures from the local market and associated neutral images from the international affective picture system. Thirty graduate students were exposed to image stimuli, followed by a distractor task and a recognition task. After the normality test, reaction times (RT), and false recognition rate of brands and neutral images were statistically compared using a pairwise t-test.

Conclusion: The results showed a significant decrease in reaction time (RT) and an increase in the false recognition rate of brand pictures compared to neutral images. Interestingly, the effect of gender on the creation of false memory by autobiographical brand images was not significant. We hope these findings can pave the way for a better understanding of the false memory mechanism.

Highlights: Autobiographical brand images give a higher chance of false memory as compared to neutral imagesMen and women do not differ in the formation of false memoryReaction time in false memory is longer than in true memory.False positives create more cognitive load.

Plain language summary: We see many images around us every day, such as the image of different brands in our daily shopping, which puts us in front of different types of images, many of which are old, these brands become part of our life memories, and their images are aspects of autobiography. Therefore, these brands can form false memories for people. The image stimuli of this study are to investigate whether these images can form false memories or not. The results showed that the images that we see every day in the street of the supermarket and can change our memories.

Introduction: Paranormal beliefs are defined as the belief in extrasensory perception, precognition, witchcraft, and telekinesis, magical thinking, psychokinesis, superstitions. Previous studies corroborate that executive brain functions underpin paranormal beliefs. To test this hypotheses, neurophysiological studies of brain activity are required.

Methods: A sample of 20 students (10 girls, Mean±SD age: 22.50±4.07 years) were included in the current study. The absolute power of resting-state electroencephalogram (EEG) was analyzed in intra-hemispheric and inter-hemispheric coherence with eyes open. The paranormal beliefs were determined based on the total score of the revised paranormal belief scale (RPBS).

Results: The results of this study demonstrated a significant negative relationship between paranormal beliefs and resting-state EEG in alpha band activity in the frontal lobe (left hemisphere), EEG coherence of alpha and β1, β2, and gamma band activities in the frontal lobe (right hemisphere) and coherence of alpha and β1, β2 and gamma band activities between frontal regions (two hemispheres). In addition, the results showed that coherence of α, α1, β, and β2 band activities between the frontal lobe (right hemispheres) and the EEG coherence of Δ, α1, and beta band activities in the frontal lobe (two hemispheres) predict paranormal beliefs.

Conclusion: This study confirms the connection of executive brain functions to paranormal beliefs and determines that frontal brain function may contribute to paranormal beliefs.

Highlights: Paranormal beliefs were negatively related to the EEG coherence.Paranormal beliefs were associated with EEG coherence in the right frontal lobe.We found a negative correlation between paranormal beliefs and the EEG coherence in the frontal lobes.EEG coherence the frontal lobes predicted paranormal beliefs.

Plain language summary: Paranormal beliefs were negatively related to the EEG coherence. They were associated with EEG coherence in the right frontal lobe. In this study, we found a negative correlation between paranormal beliefs and the EEG coherence in the frontal lobes. EEG coherence the frontal lobes predicted paranormal beliefs.

Introduction: Living near high-voltage power lines and exposure to high-frequency electromagnetic fields (EMFs) is a potentially serious hazard to animal and human health. The present study was conducted to evaluate the effect of high-frequency EMFs from simulated high-voltage electric towers on cognitive, anatomical, and biological changes in the male macaque.

Methods: In this study, two Rhesus macaque were recruited, one experimental and one control. The experimental subject was exposed to EMFs from 3 kV/m simulated electric towers with a specific protocol and the control subject was tested without irradiation (4h per day, for 30 days). All required tests were performed before and after the intervention on experimental and control monkeys. The anatomical alternation of the prefrontal area (PFA) was measured by MRI images. All tests were performed on irradiated and control animals before and after the intervention and the results were compared between irradiated and control animals.

Results: The results of the present study indicated increased white blood cell counts after high-frequency EMFs irradiation. Also, the red blood cell counts showed a decreasing trend after irradiation. The plasma adrenaline level increased after irradiation. Besides, the blood glucose levels increased after irradiation. The PFA was different before and after the irradiation. Moreover, some behavioral disorders, such as fatigue, drowsiness, anorexia, and insomnia were observed after irradiation.

Conclusion: The results of biological tests and MRI showed an elevated risk of immunodeficiency disorders, weakness, and behavioral disorders. People who live or work near high-voltage electric towers with high-frequency EMFs are warned.

Highlights: Magnetic, and electric fields from high pressure towers caused negative effects in terms of biology and even anatomical changes in the prefrontal part of the brain.Disturbance in the prefrontal part of the brain caused the monkey's cognitive and behavioral disorder.An increase in white blood cells, a decrease in red blood cells, and an increase in the adrenaline and blood sugar were indicative of biological disorders after wave exposure in male rhesus monkeys.The effects of magnetic and electric fields resulting from high pressure towers on the nerves and psyche require health researchers to do more studies.

Plain language summary: Today, one of the factors that threaten the cognitive and behavioral health of humans and animals is living in the vicinity of magnetic and electric fields resulting from the power transmission of high-pressure towers. These fields cause cognitive and behavioral disorders in living beings. Therefore, because it threatens the cognitive health of creatures, it needs more research.

Introduction: This study aims to investigate the attentional bias toward drug-related stimuli along with subjective craving after encountering such stimuli in methamphetamine users. Studies of cue reactivity have confirmed a bias in attention and gaze toward drug-related stimuli for most substances; however, methamphetamine drugs are less studied through a direct measure, such as eye tracking.

Methods: A total of 30 male subjects in the case group (methamphetamine users) and 36 subjects in the control group (no prior drug use) participated in this study. The participant's eye movement data were collected while they were viewing pairs of drug-related and non-drug images in a dot-probe paradigm. Craving was assessed via a self-report questionnaire on a scale of 0 to 10 before and after the psychophysical task.

Results: The analysis of eye-movement data showed a meaningful gaze bias toward cue images (drug-related) in the case group. Additionally, the gaze duration on cue images was significantly higher in the case group, in contrast to the control group. The same effect was observed in analyzing the dot-probe task; that is, the mean reaction time to a probe that replaced a cue image was significantly lower. The mean of the first-fixation measure in the control group was not significantly higher than chance; however, the percentage of the first-fixation on cue images in the drug users was meaningfully biased. Reported craving was significantly greater after performing the task compared to before.

Conclusion: Our results indicated an attentional bias toward drug-related cues in methamphetamine users as well as subjective craving after encountering such cues.

Highlights: The gaze duration on cue images was significantly higher in methamphetamine users.The mean reaction time to a probe that replaced a cue image was significantly lower in methamphetamine users compared to the control group.The mean of the first-fixation measure in the case group was significantly better than chance.Craving was reported to be significantly greater after performing the task.

Plain language summary: Substance users tend to focus on the stimuli associated with substances. This is known as attention bias. Attention bias leads to increased craving. Attention bias for various substances has been previously reported; however, methamphetamine attention bias has not been evaluated so far. In this study, we measured the attention bias toward stimuli related to methamphetamine in methamphetamine users and control subjects with direct (eye tracking) and indirect (dot probe paradigm) methods. In addition, we measured the number of cravings in the case group. Our results confirmed the bias in attention toward methamphetamine-related stimuli in the case group compared to the control group.

Introduction: Lack of high-quality sleep causes severe side effects like anxiety and changes in plasma concentration of oxalate. The current study investigated the impact of local extremely low-frequency magnetic fields (ELF-MFs) on inducing sleep (sleepiness) and anxiety in male rats.

Methods: In this experimental study, 40 male rats were divided into four groups (n=10 for each group). The ELF-MF exposure (0, 10, and 18 Hz) was applied with an intensity of 200μT for three days (10 min/d). The sham-treated animal did not receive ELF-MF. Serum levels of oxalic acid (OA) and sleepiness were measured before and after the last exposure to ELF-MF or sham. Anxiety, sleepiness, and OA were measured using the elevated plus maze, open-field test (OFT), and ELISA test.

Results: A comparison of oxalate levels before and after exposure to ELF-MF revealed that ELF-MF (10 Hz) decreased the serum level of oxalate (P<0.05). Comparing open/closed arm entry (in an elevated plus maze) between before and after exposure to ELFMF revealed significant differences. Also, frequency, velocity, and distance moved were decreased in the open-field test.

Conclusion: Results of the present study demonstrated that ELF-MF with short-time exposure may modulate the metabolism of OA and may modulate anxiety-like behavior or kind of induction of sleepiness in male rats.

Highlights: Oxalate acid concentration may reduce after short time ELF-MF exposure.Locomotor activity in male rats may decrease after the ELF-MF exposure.Short time ELF-MF exposure may induce sleepiness in male rats that may be used to treat sleep disorders.

Plain language summary: It is necessary for a person to have good sleep to feel happy during the day. The usual way to treat the patient's sleep disorders is drug therapy, but there are some non-pharmacological treatments such as cognitive behavioral therapy and proper diet. In this study we decided to evaluate the effect of ELF-MFs on sleep induction (sleepiness) in male rats by assessing behavioral tests and measuring oxalate acid density. The results showed that the activity of rats and oxalate acid concentration reduced after ELF-MF exposure. This was consistent with results of the plus maze test and the reduction of velocity, frequency and in the open-field test can be attributed to sleepiness. The results of this research showed that ELF-MF with short time exposure may modulate the anxiety-like behavior or kind of induction of sleepiness in male rats. This effect may be used to treat sleep disorders and requires further human studies.

Introduction: Neuroimaging evidence has shown the relationship of intelligence with several structural brain properties in normal individuals. However, this relationship with attention deficit hyperactivity disorder (ADHD) needs to be investigated.

Methods: We estimated grey matter (GM) density of the brain using magnetic resonance imaging (MRI) scan on 56 ADHD individuals, including 30 combined individuals (Mean±SD age: 10.44±2.41, intelligence quotient: [IQ]=112.13±13.15, male, 24 right hands) and 26 inattentive individuals (mean age =11.39±2.1, IQ=107.44±13.98, male, 28 right hands) as well as 30 IQ matched healthy control group (mean age=11.08±2.15, IQ=115±13.56, male, 23 right hands).

Results: In this study, two statistical approaches were used. In the first approach, region-based as well as the whole association patterns between full-scale IQ and GM were computed and compared between groups. The second approach was to examine the differential pattern of GM density without considering IQ in three groups.

Conclusion: Results showed significant differences between the ADHD group and the control. This finding could indicate that intelligence is not purely based on the density of GM in certain brain regions; it is a dynamic phenomenon and drastically changes neurodevelopmental disorders.

Highlights: In ADHDs as compared to healthy controls the relation between GM and IQ was decreased at right hemisphere;In ADHDs as compared to healthy controls the relation between GM and IQ was increased at left hemisphere;Differenceses of the observed relation between control group and IQ matched ADHDs suggest a compensatory mechanism in ADHDs to maintaine an adequate cognitive performance;GM is not the only determiner of intelligence. IQ score may be affected by neural dynamic of the brain; therefore, the structural covariate could be a better alternative for GM density.

Plain language summary: In this study, we estimated the relation between GM density and IQ score in 2 subtypes of ADHD (combined and inattentive) and IQ matched healthy control group. We compared the association between groups and found that the pattern of association in ADHDs were different from controls. In the other words, the decreased association at right hemisphere, were compensated by increased association at left hemisphere in ADHDs to maintaine adequate performance. We conclude that, the brain structure is not the single determiner of intelligence, rather intelligence may underpine by neural dynamics of the brain. Therefore, the structural covariate may be a better alternative for GM density.