Semi-supervised random forest regression model based on co-training and grouping with information entropy for evaluation of depression symptoms severity.

Semi-supervised learning has always been a hot topic in machine learning. It uses a large number of unlabeled data to improve the performance of the model. This paper combines the co-training strategy and random forest to propose a novel semi-supervised regression algorithm: semi-supervised random forest regression model based on co-training and grouping with information entropy (E-CoGRF), and applies it to the evaluation of depression symptoms severity.

A Method of Biomedical Information Classification Based on Particle Swarm Optimization with Inertia Weight and Mutation.

With the rapid development of information technology and biomedical engineering, people can get more and more information. At the same time, they begin to study how to apply the advanced technology in biomedical information. The main research of this paper is to optimize the machine learning method by particle swarm optimization (PSO) and apply it in the classification of biomedical data.

Neural Basis of Depression Related to a Dominant Right Hemisphere: A Resting-State fMRI Study.

Background: In the past, studies on the lateralization of the left and right hemispheres of the brain suggested that depression is dominated by the right hemisphere of the brain, but the neural basis of this theory remains unclear.

Method: Functional magnetic resonance imaging of the brain was performed in 22 depressive patients and 15 healthy controls. The differences in the mean values of the regional homogeneity (ReHo) of two groups were compared, and the low-frequency amplitudes of these differential brain regions were compared.

Emotion recognition from multichannel EEG signals using K-nearest neighbor classification.

Background: Many studies have been done on the emotion recognition based on multi-channel electroencephalogram (EEG) signals.

Objective: This paper explores the influence of the emotion recognition accuracy of EEG signals in different frequency bands and different number of channels.

Methods: We classified the emotional states in the valence and arousal dimensions using different combinations of EEG channels.

Emotional working memory in patients with major depressive disorder.

Objective This study was performed to examine the working memory (WM) encoding and retrieval abilities in patients with major depressive disorder (MDD) and determine whether a mood-congruent memory effect is present. Methods The modified Sternberg WM paradigm with positive, negative, and neutral emotional pictures was used to investigate the WM abilities of 26 patients with MDD and 26 healthy controls (HCs). Results No significant difference in picture WM was found between the MDD and HC groups; however, the accuracy of picture position WM was significantly lower and the response time was significantly longer in the MDD than HC group, regardless of the picture or position WM.

Attentional bias scores in patients with depression and effects of age: a controlled, eye-tracking study.

Objective To compare the attentional bias of depressed patients and non-depressed control subjects and examine the effects of age using eye-tracking technology in a free-viewing set of tasks. Methods Patients with major depressive disorder (MDD) and non-depressed control subjects completed an eye-tracking task to assess attention of processing negative, positive and neutral facial expressions. In this cross-sectional study, the tasks were separated in two types (neutral versus happy faces and neutral versus sad faces) and assessed in two age groups ('young' [18-30 years] and 'middle-aged' [31-55 years]).

The functional architectures of addition and subtraction: Network discovery using fMRI and DCM.

The neuronal mechanisms underlying arithmetic calculations are not well understood but the differences between mental addition and subtraction could be particularly revealing. Using fMRI and dynamic causal modeling (DCM), this study aimed to identify the distinct neuronal architectures engaged by the cognitive processes of simple addition and subtraction. Our results revealed significantly greater activation during subtraction in regions along the dorsal pathway, including the left inferior frontal gyrus (IFG), middle portion of dorsolateral prefrontal cortex (mDLPFC), and supplementary motor area (SMA), compared with addition.

Alleviated negative rather than positive attentional bias in patients with depression in remission: an eye-tracking study.

Objective To investigate attentional bias toward happy and sad faces in remitted depressed (RD) patients compared with healthy control (HC) subjects. Methods This cross-sectional study enrolled RD patients and sex- and age-matched HC subjects. Eye movement data were acquired for all study participants while free viewing a 2 × 2 matrix of emotional faces.

The Parahippocampal Cortex Mediates Contextual Associative Memory: Evidence from an fMRI Study.

The parahippocampal cortex (PHC) plays a key role in episodic memory, spatial processing, and the encoding of novel stimuli. Recent studies proposed that the PHC is largely involved in contextual associative processing. Consequently, the function of this region has been a hot debate in cognitive neuroscience.

Task and Resting-State fMRI Reveal Altered Salience Responses to Positive Stimuli in Patients with Major Depressive Disorder.

Altered brain function in patients with major depressive disorder (MDD) has been repeatedly demonstrated by task-based and resting-state studies, respectively. However, less is known concerning whether overlapped abnormalities in functional activities across modalities exist in MDD patients. To find out the answer, we implemented an fMRI experiment and collected both task and resting-state data from 19 MDD patients and 19 matched, healthy, controls.

Emotion, working memory, and cognitive control in patients with first-onset and previously untreated minor depressive disorders.

Objective: To explore working memory and the ability to process different emotional stimuli in patients with first-onset and untreated minor (mild or moderate) depression.

Methods: Patients with first-onset and previously untreated minor depression, and healthy controls, were enrolled. Using a modified Sternberg working memory paradigm to investigate the combined effects of emotional stimuli with working memory, participants were exposed to experimental stimuli comprising pictures that represented positive, neutral and negative emotions.

Cognitive Behavioral Performance of Untreated Depressed Patients with Mild Depressive Symptoms.

This study evaluated the working memory performance of 18 patients experiencing their first onset of mild depression without treatment and 18 healthy matched controls. The results demonstrated that working memory impairment in patients with mild depression occurred when memorizing the position of a picture but not when memorizing the pictures themselves. There was no significant difference between the two groups in the emotional impact on the working memory, indicating that the attenuation of spatial working memory was not affected by negative emotion; however, cognitive control selectively affected spatial working memory.

The Effects of Gender Differences in Patients with Depression on Their Emotional Working Memory and Emotional Experience.

A large amount of research has been conducted on the effects of sex hormones on gender differences in patients with depression, yet research on cognitive differences between male and female patients with depression is insufficient. This study uses emotion pictures to investigate the differences of the emotional working memory ability and emotional experience in male and female patients with depression. Despite identifying that the working memory of patients with depression is impaired, our study found no significant gender differences in emotional working memory.

Recruitment of the ventral and dorsal streams in statistical graph comprehension: An fMRI study.

Background: Although many previous studies have focused on statistical graph comprehension in cognitive psychology, there is no consensus among them.

Objective: Brain neuroimaging studies on the statistical graph comprehension are useful to account for the cognitive mechanism of interpreting statistical graphic information.

Methods: The present study used two experimental conditions, a statistical graph (SG) and a statistical graph with text (SGT), and one control condition, a text (ST), where the ST task was a verbal description of the information from the SG, and when the SGT is a mixed graph + textual description.

Neural substrates of data-driven scientific discovery: an fMRI study during performance of number series completion task.

Although much has been known about how humans psychologically perform data-driven scientific discovery, less has been known about its brain mechanism. The number series completion is a typical data-driven scientific discovery task, and has been demonstrated to possess the priming effect, which is attributed to the regularity identification and its subsequent extrapolation. In order to reduce the heterogeneities and make the experimental task proper for a brain imaging study, the number magnitude and arithmetic operation involved in number series completion tasks are further restricted.

Parietal cortex and information granularity in labile and stable learning.

We investigated the effects of rule learning based on information granularity. Using two homogeneous Boolean arithmetic tasks, we examined parietal cortex activity during the calculation of labile and stabilized learning. The results revealed stability-related behavioral advantages in a comparison of granularity-based effects with labile learning of Boolean problems.

The role of the DLPFC in inductive reasoning of MCI patients and normal agings: an fMRI study.

Previous studies of young people have revealed that the left dorsolateral prefrontal cortex (DLPFC) plays an important role in inductive reasoning. An fMRI experiment was performed in this study to examine whether the left DLPFC was involved in inductive reasoning of MCI patients and normal aging, and whether the activation pattern of this region was different between MCI patients and normal aging. The fMRI results indicated that MCI patients had no difference from normal aging in behavior performance (reaction time and accuracy) and the activation pattern of DLPFC.