Neurocognitive

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Neurocognitive functions are cognitive functions closely linked to the function of particular areas, neural pathways, or cortical networks in the brain substrate layers of neurological matrix at the cellular molecular level. Therefore, their understanding is closely linked to the practice of neuropsychology and cognitive neuroscience, two disciplines that broadly seek to understand how the structure and function of the brain relate to cognition and behaviour.

Neural pathway

A neural pathway is the connection formed by axons that project from neurons to make synapses onto neurons in another location, to enable a signal to be sent from one region of the nervous system to another. Neurons are connected by a single axon, or by a bundle of axons known as a nerve tract, or fasciculus. Shorter neural pathways are found within grey matter in the brain, whereas longer projections, made up of myelinated axons, constitute white matter.

Cerebral cortex Part of a mammals brain

The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is separated into two cortices, by the longitudinal fissure that divides the cerebrum into the left and right cerebral hemispheres. The two hemispheres are joined beneath the cortex by the corpus callosum. The cerebral cortex is the largest site of neural integration in the central nervous system. It plays a key role in attention, perception, awareness, thought, memory, language, and consciousness.

Brain organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals

A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 14–16 billion neurons, and the estimated number of neurons in the cerebellum is 55–70 billion. Each neuron is connected by synapses to several thousand other neurons. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells.

Contents

A neurocognitive deficit is a reduction or impairment of cognitive function in one of these areas, but particularly when physical changes can be seen to have occurred in the brain, such as after neurological illness, mental illness, drug use, or brain injury. [1]

Medication substance used to diagnose, cure, treat, or prevent disease

A medication is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and relies on the science of pharmacology for continual advancement and on pharmacy for appropriate management.

Acquired brain injury type of brain damage caused by events after birth, rather than by a congenital disorder

Acquired brain injury (ABI) is brain damage caused by events after birth, rather than as part of a genetic or congenital disorder such as fetal alcohol syndrome, perinatal illness or perinatal hypoxia. ABI can result in cognitive, physical, emotional, or behavioural impairments that lead to permanent or temporary changes in functioning. These impairments result from either traumatic brain injury or nontraumatic injury derived from either an internal or external source. ABI does not include damage to the brain resulting from neurodegenerative disorders.

A clinical neuropsychologist may specialise in using neuropsychological tests to detect and understand such deficits, and may be involved in the rehabilitation of an affected person. The discipline that studies neurocognitive deficits to infer normal psychological function is called cognitive neuropsychology.

Neuropsychological tests are specifically designed tasks used to measure a psychological function known to be linked to a particular brain structure or pathway. Tests are used for research into brain function and in a clinical setting for the diagnosis of deficits. They usually involve the systematic administration of clearly defined procedures in a formal environment. Neuropsychological tests are typically administered to a single person working with an examiner in a quiet office environment, free from distractions. As such, it can be argued that neuropsychological tests at times offer an estimate of a person's peak level of cognitive performance. Neuropsychological tests are a core component of the process of conducting neuropsychological assessment, along with personal, interpersonal and contextual factors.

Rehabilitation of sensory and cognitive function typically involves methods for retraining neural pathways or training new neural pathways to regain or improve neurocognitive functioning that has been diminished by disease or trauma. Three common neuropsychological problems treatable with rehabilitation are attention deficit/hyperactivity disorder (ADHD), concussion, and spinal cord injury. Rehabilitation research and practices are a fertile area for clinical neuropsychologists, rehabilitation psychologists, and others.

Cognitive neuropsychology is a branch of cognitive psychology that aims to understand how the structure and function of the brain relates to specific psychological processes. Cognitive psychology is the science that looks at how mental processes are responsible for our cognitive abilities to store and produce new memories, produce language, recognize people and objects, as well as our ability to reason and problem solve. Cognitive neuropsychology places a particular emphasis on studying the cognitive effects of brain injury or neurological illness with a view to inferring models of normal cognitive functioning. Evidence is based on case studies of individual brain damaged patients who show deficits in brain areas and from patients who exhibit double dissociations. Double dissociations involve two patients and two tasks. One patient is impaired at one task but normal on the other, while the other patient is normal on the first task and impaired on the other. For example, patient A would be poor at reading printed words while still being normal at understanding spoken words, while the patient B would be normal at understanding written words and be poor at understanding spoken words. Scientists can interpret this information to explain how there is a single cognitive module for word comprehension. From studies like these, researchers infer that different areas of the brain are highly specialised. Cognitive neuropsychology can be distinguished from cognitive neuroscience, which is also interested in brain damaged patients, but is particularly focused on uncovering the neural mechanisms underlying cognitive processes.

Etymology

The term neurocognitive is a recent addition to the nosology of clinical Psychiatry and Psychology. It was used rarely before the publication of the DSM-5, which updated the psychiatric classification of disorders listed in the "Delirium, Dementia, and Amnestic and Other Cognitive Disorders" chapter of the DSM-IV. [2] Following the 2013 publication of the DSM-5, use of the term "neurocognitive" increased steadily. [3]

Nosology is the branch of medical science that deals with the classification of diseases.

Psychiatry is the medical specialty devoted to the diagnosis, prevention, and treatment of mental disorders. These include various maladaptations related to mood, behaviour, cognition, and perceptions. See glossary of psychiatry.

Psychology is the science of behavior and mind. Psychology includes the study of conscious and unconscious phenomena, as well as feeling and thought. It is an academic discipline of immense scope. Psychologists seek an understanding of the emergent properties of brains, and all the variety of phenomena linked to those emergent properties, joining this way the broader neuroscientific group of researchers. As a social science it aims to understand individuals and groups by establishing general principles and researching specific cases.

Adding the prefix "neuro-" to the word "cognitive" is an example of pleonasm because, analogous to expressions like "burning fire" and "black darkness," the prefix "neuro-" adds no information to "cognitive." Adding "neuro-" to the more common, original term "cognitive" could give the appearance of alluding to a non-neurologic form of cognition, and in the field of clinical Neurology, clinicians continue using the simpler term "cognitive," possibly due to an absence of evidence for human cognitive processes that do not involve the nervous system.

Pleonasm is the use of more words or parts of words than are necessary or sufficient for clear expression: for example black darkness or burning fire. Such redundancy is, by traditional rhetorical criteria, a manifestation of tautology, and might be considered a fault of style. Pleonasm may also be used for emphasis or because the phrase has become established in a certain form. Tautology and pleonasm are not consistently differentiated in the literature.

Neurology Medical specialty dealing with disorders of the nervous system

Neurology is a branch of medicine dealing with disorders of the nervous system. Neurology deals with the diagnosis and treatment of all categories of conditions and disease involving the central and peripheral nervous systems, including their coverings, blood vessels, and all effector tissue, such as muscle. Neurological practice relies heavily on the field of neuroscience, the scientific study of the nervous system.

See also

Cognition is "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses many aspects of intellectual functions and processes such as attention, 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 and generate new knowledge.

Cognitive neuroscience is the scientific field that is concerned with the study of the biological processes and aspects that underlie cognition, with a specific focus on the neural connections in the brain which are involved in mental processes. It addresses the questions of how cognitive activities are affected or controlled by neural circuits in the brain. Cognitive neuroscience is a branch of both neuroscience and psychology, overlapping with disciplines such as behavioral neuroscience, cognitive psychology, physiological psychology and affective neuroscience. Cognitive neuroscience relies upon theories in cognitive science coupled with evidence from neurobiology, and computational modeling.

Cognitive rehabilitation therapy

Cognitive rehabilitation refers to a wide range of evidence-based interventions designed to improve cognitive functioning in brain-injured or otherwise cognitively impaired individuals to restore normal functioning, or to compensate for cognitive deficits. It entails an individualized program of specific skills training and practice plus metacognitive strategies. Metacognitive strategies include helping the patient increase self-awareness regarding problem-solving skills by learning how to monitor the effectiveness of these skills and self-correct when necessary.

Related Research Articles

Neuropsychology is the study and characterization of the behavioral modifications that follow a neurological trauma or condition. It is both an experimental and clinical field of psychology that aims to understand how behavior and cognition are influenced by brain functioning and is concerned with the diagnosis and treatment of behavioral and cognitive effects of neurological disorders. Whereas classical neurology focuses on the pathology of the nervous system and classical psychology is largely divorced from it, neuropsychology seeks to discover how the brain correlates with the mind through the study of neurological patients. It thus shares concepts and concerns with neuropsychiatry and with behavioral neurology in general. The term neuropsychology has been applied to lesion studies in humans and animals. It has also been applied in efforts to record electrical activity from individual cells in higher primates.

Anosognosia is a deficit of self-awareness, a condition in which a person with a disability is unaware of its existence. It was first named by the neurologist Joseph Babinski in 1914. Anosognosia results from physiological damage to brain structures, typically to the parietal lobe or a diffuse lesion on the fronto-temporal-parietal area in the right hemisphere, and is thus a neuropsychiatric disorder. Phenomenologically, anosognosia has similarities to denial, which is a psychological defense mechanism, attempts have been made at a unified explanation. Anosognosia is sometimes accompanied by asomatognosia, a form of neglect in which patients deny ownership of body parts such as their limbs. The term is from Ancient Greek ἀ- a-, "without", νόσος nosos, "disease" and γνῶσις gnōsis, "knowledge".

Clinical neuropsychology sub-field of neuropsychology concerned with the applied science of brain-behaviour relationships

Clinical neuropsychology is a sub-field of psychology concerned with the applied science of brain-behaviour relationships. Clinical neuropsychologists use this knowledge in the assessment, diagnosis, treatment, and or rehabilitation of patients across the lifespan with neurological, medical, neurodevelopmental and psychiatric conditions, as well as other cognitive and learning disorders. The branch of neuropsychology associated with children and young people is pediatric neuropsychology.

Cognitive neuropsychiatry is a growing multidisciplinary field arising out of cognitive psychology and neuropsychiatry that aims to understand mental illness and psychopathology in terms of models of normal psychological function. A concern with the neural substrates of impaired cognitive mechanisms links cognitive neuropsychiatry to the basic neuroscience. Alternatively, CNP provides a way of uncovering normal psychological processes by studying the effects of their change or impairment.

Neuropsychological assessment was traditionally carried out to assess the extent of impairment to a particular skill and to attempt to determine the area of the brain which may have been damaged following brain injury or neurological illness. With the advent of neuroimaging techniques, location of space-occupying lesions can now be more accurately determined through this method, so the focus has now moved on to the assessment of cognition and behaviour, including examining the effects of any brain injury or neuropathological process that a person may have experienced.

Cognitive disorders (CDs), also known as neurocognitive disorders (NCDs), are a category of mental health disorders that primarily affect cognitive abilities including learning, memory, perception, and problem solving. Neurocognitive disorders include delirium and mild and major neurocognitive disorder. They are defined by deficits in cognitive ability that are acquired, typically represent decline, and may have an underlying brain pathology. The DSM-5 defines six key domains of cognitive function: executive function, learning and memory, perceptual-motor function, language, complex attention, and social cognition.

Frontal lobe disorder

Frontal lobe disorder is an impairment of the frontal lobe that occurs due to disease or head trauma. The frontal lobe of the brain plays a key role in higher mental functions such as motivation, planning, social behaviour, and speech production. A frontal lobe syndrome can be caused by a range of conditions including head trauma, tumours, degenerative diseases, neurosurgery and cerebrovascular disease. Frontal lobe impairment can be detected by recognition of typical clinical signs, use of simple screening tests, and specialist neurological testing.

Edith F. Kaplan was an American psychologist. She was a pioneer of neuropsychological tests and did most of her work at the Boston VA Hospital. Kaplan is known for her promotion of clinical neuropsychology as a specialty area in psychology. She examined brain-behavioral relationships in aphasia, apraxia, developmental issues in clinical neuropsychology, as well as normal and abnormal aging. Kaplan helped develop a new method of assessing brain function with neuropsychological assessment, called "The Boston Process Approach."

Behavioral neurology is a subspecialty of neurology that studies the impact of neurological damage and disease upon behavior, memory, and cognition, and the treatment thereof. Two fields associated with behavioral neurology are neuropsychiatry and neuropsychology. In the United States, 'Behavioral Neurology and Neuropsychiatry' has been recognized as a single subspecialty by the United Council for Neurologic Subspecialties (UCNS) since 2004.

The NINCDS-ADRDA Alzheimer's Criteria were proposed in 1984 by the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association and are among the most used in the diagnosis of Alzheimer's disease (AD). These criteria require that the presence of cognitive impairment and a suspected dementia syndrome be confirmed by neuropsychological testing for a clinical diagnosis of possible or probable AD; while they need histopathologic confirmation for the definitive diagnosis. They specify as well eight cognitive domains that may be impaired in AD. These criteria have shown good reliability and validity.

Elizabeth Kerr Warrington FRS is a British neuropsychologist specialised in the study of dementia. She holds a PhD in Psychology visual processing and is now an emeritus professor of clinical neuropsychology at the University College London. She formerly worked as the Head of the Department of Neuropsychology at the National Hospital for Neurology and Neurosurgery where she is also a member of the Dementia Research Centre. She was made a Fellow of the Royal Society in 1986.

Eleanor M. Saffran, an American neuroscientist, was a researcher in the field of Cognitive Neuropsychology. Her interest in Neuropsychology began at the Baltimore City hospitals of Johns Hopkins University, where her research unit focused on neurological patients with language or cognitive impairments. In papers published between 1976 and 1982, Dr. Saffran spelled out the methodological tenets of “cognitive neuropsychology” exemplified in her studies of aphasia, alexia, auditory verbal agnosia, and short-term memory impairment.

Neurological disorder Disease of anatomical entity that is located in the central nervous system or located in the peripheral nervous system

A neurological disorder is any disorder of the nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord or other nerves can result in a range of symptoms. Examples of symptoms include paralysis, muscle weakness, poor coordination, loss of sensation, seizures, confusion, pain and altered levels of consciousness. There are many recognized neurological disorders, some relatively common, but many rare. They may be assessed by neurological examination, and studied and treated within the specialities of neurology and clinical neuropsychology.

In psychology and neuroscience, executive dysfunction, or executive function deficit, is a disruption to the efficacy of the executive functions, which is a group of cognitive processes that regulate, control, and manage other cognitive processes. Executive dysfunction can refer to both neurocognitive deficits and behavioural symptoms. It is implicated in numerous psychopathologies and mental disorders, as well as short-term and long-term changes in non-clinical executive control.

Alice Medalia is an American clinical neuropsychologist and international leader in the field of psychiatric rehabilitation. She is best known for her work treating cognitive deficits in people with psychiatric disorders. This subspecialty is known as cognitive remediation.

Ian Robertson is a Scottish neuroscientist and clinical psychologist, and Professor of Psychology at Trinity College Dublin.

Pasquale Calabrese born 27 February 1961 in Naples, Italy, is an Italian professor of clinical neurosciences at the University of Basel, Faculty of Psychology, Department of Molecular and Cognitive Neurosciences. He is a neuroscientist, experimental neurologist and medical neuropsychologist.

References

  1. Blazer, Dan (2013). "Commentary: Neurocognitive Disorders in DSM-5". American Journal of Psychiatry. 170 (6): 585–587. doi:10.1176/appi.ajp.2013.13020179.
  2. Sachdev, PS; Blacker, D; Blazer, DG; Ganguli, M; Jeste, DV; Paulsen, JS; et al. (2014). "Classifying neurocognitive disorders: the DSM-5 approach". Nat Rev Neurol. 10 (11): 634–42. doi:10.1038/nrneurol.2014.181. PMID   25266297.
  3. https://trends.google.com/trends/explore/TIMESERIES/1555462200?hl=en-US&tz=300&date=all&geo=US&q=neurocognitive,dsm-5&sni=3

Further reading