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Functional MRI Methods And Findings In Schizophrenia
Functional MRI imaging methods have allowed researchers to combine neurocognitive testing with structural neuroanatomical measures, consider cognitive and affective paradigms, and create computer-aided diagnosis techniques and algorithms. Functional MRI has several benefits, such as its non-invasive quality, relatively high spatial resolution, and decent temporal resolution. This is due the influential development in the scanner hardware, where it now allows for technicians to retrieve higher resolution images in a shorter amount of time. Additionally, there has been an improved motion correction and harmonization, which both aid in the generalizability and replication of findings in schizophrenia research. Recent studies have used fMRI to explore specific brain networks, such as the salience network and default mode network, to understand their roles in schizophrenia-related symptoms. Alterations in these networks may affect self-referential thoughts and responses to external stim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Magnetic Resonance Imaging
Functional magnetic resonance imaging or functional MRI (fMRI) measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases. The primary form of fMRI uses the blood-oxygen-level dependent (BOLD) contrast, discovered by Seiji Ogawa in 1990. This is a type of specialized brain and body scan used to map neuron, neural activity in the brain or spinal cord of humans or other animals by imaging the change in blood flow (hemodynamic response) related to energy use by brain cells. Since the early 1990s, fMRI has come to dominate brain mapping research because it does not involve the use of injections, surgery, the ingestion of substances, or exposure to ionizing radiation. This measure is frequently corrupted by noise from various sources; hence, statistical procedures are used to extract the underlying si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Treatment And Control Groups
In the design of experiments, hypotheses are applied to experimental units in a treatment group. In comparative experiments, members of a control group receive a standard treatment, a placebo, or no treatment at all. There may be more than one treatment group, more than one control group, or both. A placebo control group can be used to support a double-blind study, in which some subjects are given an ineffective treatment (in medical studies typically a sugar pill) to minimize differences in the experiences of subjects in the different groups; this is done in a way that ensures no participant in the experiment (subject or experimenter) knows to which group each subject belongs. In such cases, a third, non-treatment control group can be used to measure the placebo effect directly, as the difference between the responses of placebo subjects and untreated subjects, perhaps paired by age group or other factors (such as being twins). For the conclusions drawn from the results of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mental Disorder
A mental disorder, also referred to as a mental illness, a mental health condition, or a psychiatric disability, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. A mental disorder is also characterized by a clinically significant disturbance in an individual's cognition, emotional regulation, or behavior, often in a society, social context. Such disturbances may occur as single episodes, may be persistent, or may be relapsing–remitting. There are many different types of mental disorders, with signs and symptoms that vary widely between specific disorders. A mental disorder is one aspect of mental health. The causes of mental disorders are often unclear. Theories incorporate findings from a range of fields. Disorders may be associated with particular regions or functions of the brain. Disorders are usually Medical diagnosis, diagnosed or assessed by a mental health professional, such as a Clinical psychology#Profes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frontoparietal Network
The frontoparietal network (FPN), generally also known as the central executive network (CEN) or, more specifically, the lateral frontoparietal network (L-FPN) (see Nomenclature), is a large-scale brain network primarily composed of the dorsolateral prefrontal cortex and posterior parietal cortex, around the intraparietal sulcus. It is involved in sustained attention, complex problem-solving and working memory. The FPN is one of three networks in the so-called triple-network model, along with the salience network and the default mode network (DMN). The salience network facilitates switching between the FPN and DMN. Anatomy The FPN is primarily composed of the rostral lateral and dorsolateral prefrontal cortex (especially the middle frontal gyrus) and the anterior inferior parietal lobule. Additional regions include the middle cingulate gyrus and potentially the dorsal precuneus, posterior inferior temporal lobe, dorsomedial thalamus and the head of the caudate nucleus. Func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual System
The visual system is the physiological basis of visual perception (the ability to perception, detect and process light). The system detects, phototransduction, transduces and interprets information concerning light within the visible range to construct an imaging, image and build a mental model of the surrounding environment. The visual system is associated with the eye and functionally divided into the optics, optical system (including cornea and crystalline lens, lens) and the nervous system, neural system (including the retina and visual cortex). The visual system performs a number of complex tasks based on the ''image forming'' functionality of the eye, including the formation of monocular images, the neural mechanisms underlying stereopsis and assessment of distances to (depth perception) and between objects, motion perception, pattern recognition, accurate motor coordination under visual guidance, and colour vision. Together, these facilitate higher order tasks, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perception
Perception () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous system, which in turn result from physical or chemical stimulation of the sensory system.Goldstein (2009) pp. 5–7 Vision involves light striking the retina of the eye; smell is mediated by odor molecules; and hearing involves pressure waves. Perception is not only the passive receipt of these signals, but it is also shaped by the recipient's learning, memory, expectation, and attention. Gregory, Richard. "Perception" in Gregory, Zangwill (1987) pp. 598–601. Sensory input is a process that transforms this low-level information to higher-level information (e.g., extracts shapes for object recognition). The following process connects a person's concepts and expectations (or knowledge) with restorative and selective mechanisms, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cognition
Cognition is the "mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, imagination, intelligence, the formation of knowledge, memory and working memory, judgment and evaluation, reasoning and computation, problem-solving and decision-making, comprehension and production of language. Cognitive processes use existing knowledge to discover new knowledge. Cognitive processes are analyzed from very different perspectives within different contexts, notably in the fields of linguistics, musicology, anesthesia, neuroscience, psychiatry, psychology, education, philosophy, anthropology, biology, systemics, logic, and computer science. These and other approaches to the analysis of cognition (such as embodied cognition) are synthesized in the developing field of cognitive science, a progressively autonomou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basic Symptoms Of Schizophrenia
Basic symptoms of schizophrenia are subjective symptoms, described as experienced from a person's perspective, which show evidence of underlying psychopathology. Basic symptoms have generally been applied to the assessment of people who may be at-risk mental state, at risk to develop psychosis. Though basic symptoms are often disturbing for the person, problems generally do not become evident to others until the person is no longer able to cope with their basic symptoms. Basic symptoms are more specific to identifying people who exhibit signs of prodromal psychosis (prodrome) and are more likely to develop schizophrenia over other disorders related to psychosis. Schizophrenia is a psychotic disorder, but is not synonymous with psychosis. In the prodrome to psychosis, uncharacteristic basic symptoms develop first, followed by more characteristic basic symptoms and brief and self-limited psychotic-like symptoms, and finally the onset of psychosis. People who were assessed to be high r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matching (statistics)
Matching is a statistical technique that evaluates the effect of a treatment by comparing the treated and the non-treated units in an observational study or quasi-experiment (i.e. when the treatment is not randomly assigned). The goal of matching is to reduce bias for the estimated treatment effect in an observational-data study, by finding, for every treated unit, one (or more) non-treated unit(s) with similar observable characteristics against which the covariates are balanced out (similar to the K-nearest neighbors algorithm). By matching treated units to similar non-treated units, matching enables a comparison of outcomes among treated and non-treated units to estimate the effect of the treatment reducing bias due to confounding. Propensity score matching, an early matching technique, was developed as part of the Rubin causal model, but has been shown to increase model dependence, bias, inefficiency, and power and is no longer recommended compared to other matching methods. A si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salience Network
The salience network (SN), also referred to as the midcingulo-insular network (M-CIN) or cingulo-opercular network in anatomical parcellation schemes, is a large scale network of the human brain that is primarily composed of the anterior insula (AI) and dorsal anterior cingulate cortex (dACC). It is involved in detecting and filtering salient stimuli, as well as in recruiting relevant functional networks. Together with its interconnected brain networks, the SN contributes to a variety of complex functions, including communication, social behavior, and self-awareness through the integration of sensory, emotional, and cognitive information.Menon V. (2015) Salience Network. In: Arthur W. Toga, editor. Brain Mapping: An Encyclopedic Reference, vol. 2, pp. 597-611. Academic Press: Elsevier. https://med.stanford.edu/content/dam/sm/scsnl/documents/Menon_Salience_Network_15.pdf The network is detectable through independent component analysis of resting state fMRI images, as well as s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signs And Symptoms
Signs and symptoms are diagnostic indications of an illness, injury, or condition. Signs are objective and externally observable; symptoms are a person's reported subjective experiences. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showing on a medical scan. A symptom is something out of the ordinary that is experienced by an individual such as feeling feverish, a headache or other pains in the body, which occur as the body's immune system fights off an infection. Signs and symptoms Signs A medical sign is an objective observable indication of a disease, injury, or medical condition that may be detected during a physical examination. These signs may be visible, such as a rash or bruise, or otherwise detectable such as by using a stethoscope or taking blood pressure. Medical signs, along with symptoms, help in forming a diagnosis. Some examples of signs are nail clubbing of either the fingernail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsolateral Prefrontal Cortex
The dorsolateral prefrontal cortex (DLPFC or DL-PFC) is an area in the prefrontal cortex of the primate brain. It is one of the most recently derived parts of the human brain. It undergoes a prolonged period of maturation which lasts into adulthood. The DLPFC is not an anatomical structure, but rather a functional one. It lies in the middle frontal gyrus of humans (i.e., lateral part of Brodmann's area (BA) 9 and 46). In macaque monkeys, it is around the principal sulcus (i.e., in Brodmann's area 46). Other sources consider that DLPFC is attributed anatomically to BA 9 and 46 and BA 8, 9 and 10. The DLPFC has connections with the orbitofrontal cortex, as well as the thalamus, parts of the basal ganglia (specifically, the dorsal caudate nucleus), the hippocampus, and primary and secondary association areas of neocortex (including posterior temporal, parietal, and occipital areas). The DLPFC is also the end point for the dorsal pathway (stream), which is concerned with how t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
