神経科学英語：必須語彙とフレーズ

"cerebral cortex"

The outer layered sheet of neural tissue forming the largest part of the brain, responsible for higher cognitive functions including perception, language, and voluntary movement

"Damage to the prefrontal region of the cerebral cortex impaired the patient's capacity for executive planning and impulse control."

"hippocampus"

A seahorse-shaped structure in the medial temporal lobe critical for the formation of new declarative memories and spatial navigation

"Volumetric MRI showed marked hippocampal atrophy in patients with early Alzheimer's disease compared to age-matched controls."

"amygdala"

An almond-shaped nucleus in the anterior temporal lobe that plays a central role in processing emotional responses, particularly fear and threat detection

"Fear-conditioned stimuli produced robust activation of the bilateral amygdala in the fMRI paradigm, consistent with its role in emotional learning."

"basal ganglia"

A group of subcortical nuclei including the striatum, globus pallidus, and substantia nigra that modulate voluntary movement and reward-based learning

"The progressive loss of dopaminergic neurons projecting to the basal ganglia is the primary neuropathological hallmark of Parkinson's disease."

"corpus callosum"

The large band of white matter fibres connecting the left and right cerebral hemispheres, enabling interhemispheric communication

"Patients whose corpus callosum had been surgically severed showed striking evidence of independent functioning in each cerebral hemisphere."

"cerebellum"

A large hindbrain structure that coordinates voluntary movement, balance, and motor learning through precise timing circuits involving Purkinje cells and mossy fibres

"Cerebellar lesions produced a characteristic ataxic gait and intention tremor, confirming the cerebellum's role in fine motor coordination."

"thalamus"

A bilateral relay station in the diencephalon that routes sensory and motor signals to and from the cerebral cortex and regulates states of consciousness

"The thalamus acts as a gatekeeper for sensory information, filtering signals before they reach the cortex for conscious processing."

"prefrontal cortex"

The anterior portion of the frontal lobe involved in working memory, decision-making, social cognition, and the inhibition of inappropriate behaviour

"Adolescents show protracted maturation of the prefrontal cortex, which partly explains their relatively poor impulse control compared to adults."

"action potential"

A rapid, all-or-nothing electrical impulse propagated along a neuron's axon when the membrane potential reaches threshold, driven by sequential sodium and potassium ion flows

"The patch-clamp recordings confirmed that the neuron fired a single action potential approximately 2 ms after the depolarising current injection."

"neurotransmitter"

A chemical messenger synthesised and released by presynaptic neurons that binds to receptors on postsynaptic cells to transmit or modulate neural signals

"Glutamate is the principal excitatory neurotransmitter in the mammalian central nervous system and is critical for synaptic plasticity."

"synaptic vesicle"

A small membrane-bound organelle in the axon terminal that stores neurotransmitter molecules and fuses with the presynaptic membrane upon calcium influx to release its contents

"Electron microscopy revealed a dense cluster of synaptic vesicles docked at the active zone of the presynaptic terminal."

"postsynaptic potential"

A graded change in membrane voltage in the postsynaptic neuron following neurotransmitter binding, which can be either excitatory (EPSP) or inhibitory (IPSP)

"Summation of multiple excitatory postsynaptic potentials at the axon hillock triggered an action potential in the receiving neuron."

"reuptake"

The process by which a presynaptic neuron reabsorbs previously released neurotransmitter molecules from the synaptic cleft, terminating the signal and recycling the transmitter

"Selective serotonin reuptake inhibitors prevent the reuptake of serotonin, increasing its availability at postsynaptic receptors and alleviating depressive symptoms."

"long-term potentiation"

A persistent strengthening of synaptic transmission following repeated high-frequency stimulation, widely regarded as a cellular mechanism underlying learning and memory

"Blocking NMDA receptors prevented the induction of long-term potentiation in hippocampal slices, confirming their essential role in synaptic strengthening."

"inhibitory interneuron"

A short-range neuron that releases inhibitory neurotransmitters such as GABA to regulate the firing of nearby excitatory neurons and maintain network balance

"Parvalbumin-positive inhibitory interneurons generate gamma-frequency oscillations essential for coordinating cortical activity during cognitive tasks."

"axon terminal"

The distal end of an axon, also called the synaptic bouton, that houses neurotransmitter-filled vesicles and releases them into the synaptic cleft upon depolarisation

"Immunolabelling showed a high density of axon terminals expressing dopamine transporter in the nucleus accumbens of the reward circuit."

"functional MRI"

A neuroimaging technique that detects brain activity indirectly by measuring changes in blood oxygenation (the BOLD signal) associated with neural firing

"Functional MRI revealed increased activation in the anterior cingulate cortex during tasks requiring conflict monitoring and cognitive control."

"BOLD signal"

Blood-oxygen-level-dependent signal; the contrast mechanism underlying fMRI that reflects local changes in the ratio of oxygenated to deoxygenated haemoglobin following neural activity

"The BOLD signal reached its peak approximately five seconds after stimulus onset, consistent with the known haemodynamic response function."

"diffusion tensor imaging"

An MRI-based technique that maps white matter tract integrity by measuring the directional diffusion of water molecules along axon bundles

"Diffusion tensor imaging demonstrated reduced fractional anisotropy in the uncinate fasciculus of patients with major depressive disorder."

"EEG"

Electroencephalography; a non-invasive technique that records the summed electrical activity of cortical neurons via electrodes placed on the scalp, offering millisecond temporal resolution

"The EEG showed a characteristic pattern of alpha desynchronisation when participants transitioned from rest to active visual processing."

"PET scan"

Positron emission tomography; a nuclear imaging technique that measures regional metabolic activity or receptor binding by detecting gamma rays from an injected radioactive tracer

"A PET scan using a dopamine receptor ligand revealed significantly reduced D2 receptor availability in the striatum of patients with schizophrenia."

"voxel-based morphometry"

A computational neuroanatomical technique that statistically compares local grey matter density or volume across the whole brain between groups of participants

"Voxel-based morphometry identified clusters of reduced grey matter density in the parietal and temporal cortices of patients with mild cognitive impairment."

"resting-state network"

A set of brain regions that show correlated low-frequency fluctuations in BOLD signal during rest, reflecting intrinsic functional connectivity in the absence of an explicit task

"The default mode network is the best-characterised resting-state network and is typically deactivated during externally directed cognitive tasks."

"tractography"

A computational method applied to diffusion MRI data that reconstructs the three-dimensional trajectories of white matter fibre pathways through the brain

"Probabilistic tractography traced the corticospinal tract from the primary motor cortex down through the brainstem to the spinal cord."

"dopaminergic pathway"

A neural circuit that uses dopamine as its primary neurotransmitter; the mesolimbic and mesocortical pathways are central to reward processing, motivation, and psychiatric disorders

"Psychostimulants such as cocaine and amphetamine exert their reinforcing effects primarily by flooding the mesolimbic dopaminergic pathway with dopamine."

"serotonergic system"

The network of neurons originating mainly in the raphe nuclei of the brainstem that project widely throughout the brain and modulate mood, appetite, sleep, and pain

"Most antidepressant medications target the serotonergic system by preventing reuptake or increasing synthesis of serotonin in key limbic structures."

"GABAergic inhibition"

Neural signalling mediated by GABA (gamma-aminobutyric acid), the principal inhibitory neurotransmitter in the brain, which reduces neuronal excitability

"Benzodiazepines enhance GABAergic inhibition by allosterically potentiating GABA-A receptor function, producing anxiolytic and sedative effects."

"glutamatergic synapse"

A synapse at which glutamate is the primary neurotransmitter, activating AMPA, NMDA, and kainate receptors to drive fast excitatory transmission and synaptic plasticity

"Overactivation of glutamatergic synapses during ischaemia triggers excitotoxicity and widespread neuronal death through calcium overload."

"acetylcholine"

A neurotransmitter released at neuromuscular junctions and by cholinergic neurons in the basal forebrain and brainstem, critical for muscle contraction, arousal, and memory encoding

"The progressive loss of cholinergic neurons in the nucleus basalis of Meynert reduces acetylcholine levels and contributes to the memory deficits of Alzheimer's disease."

"noradrenergic signalling"

Neural communication mediated by noradrenaline (norepinephrine), released primarily from neurons in the locus coeruleus to regulate arousal, attention, and the stress response

"The locus coeruleus amplifies noradrenergic signalling in the forebrain during novel or threatening situations, sharpening attentional focus and encoding of salient events."

"opioid receptor"

A family of G-protein-coupled receptors (mu, delta, kappa) that bind endogenous opioid peptides and exogenous opiates to mediate analgesia, reward, and respiratory depression

"The analgesic action of morphine is primarily mediated by its agonist activity at mu-opioid receptors in the periaqueductal grey and spinal cord."

"endocannabinoid system"

A retrograde signalling system in which lipid-based endocannabinoid molecules are released by postsynaptic neurons and act on presynaptic CB1 receptors to suppress neurotransmitter release

"The endocannabinoid system plays a key role in regulating synaptic plasticity, appetite, and nociception, and is the target of exogenous cannabinoids such as THC."

"synaptic plasticity"

The ability of synapses to strengthen or weaken over time in response to changes in neural activity, forming the cellular basis of learning and memory

"Repeated pairing of pre- and postsynaptic activity induced robust synaptic plasticity in the hippocampal CA1 region, increasing the amplitude of synaptic responses by 40%."

"neurogenesis"

The process by which new neurons are generated from neural stem and progenitor cells; abundant during embryonic development and persisting in the adult hippocampus and olfactory bulb

"Physical exercise and environmental enrichment increase adult hippocampal neurogenesis, which has been associated with improved spatial memory performance."

"critical period"

A developmental window during which the nervous system is especially sensitive to environmental stimuli and experience-dependent changes in synaptic connectivity are maximally favoured

"Monocular deprivation during the critical period for visual development permanently shifts ocular dominance in the primary visual cortex towards the non-deprived eye."

"axonal sprouting"

The growth of new axonal branches from surviving neurons following injury, allowing partial re-innervation of denervated synaptic targets as part of the brain's regenerative response

"Axonal sprouting from intact corticospinal neurons partially compensated for the motor deficits caused by a unilateral cortical lesion in the rodent model."

"cortical remapping"

The reorganisation of topographic maps in the cerebral cortex following injury, sensory deprivation, or prolonged skill learning, reflecting the brain's capacity for structural and functional adaptation

"Professional violinists show cortical remapping in which the representation of the fingers of the left hand is disproportionately enlarged in the somatosensory cortex."

"myelination"

The process by which oligodendrocytes wrap axons in multiple layers of myelin sheath, dramatically increasing the speed and fidelity of electrical signal conduction

"The white matter tracts of the frontal lobe continue to undergo myelination well into early adulthood, which parallels the maturation of executive function."

"dendritic spine"

A small protrusion on a dendritic branch that forms the postsynaptic site of most excitatory synapses in the brain and whose morphology changes with synaptic strength

"Two-photon microscopy revealed that induction of long-term potentiation caused a persistent increase in the volume of dendritic spines at potentiated synapses."

"brain-derived neurotrophic factor"

BDNF; a member of the neurotrophin family that supports neuronal survival, promotes synaptic plasticity, and is a key molecular mediator of exercise-induced cognitive enhancement

"Blocking BDNF signalling with a TrkB antagonist prevented the memory-enhancing effects of voluntary wheel running in the hippocampal-dependent spatial learning task."

"neurodegeneration"

The progressive loss of neuronal structure and function over time, as seen in Alzheimer's, Parkinson's, and Huntington's diseases, often driven by protein aggregation and oxidative stress

"The hallmarks of neurodegeneration in Alzheimer's disease include the accumulation of amyloid-beta plaques and hyperphosphorylated tau neurofibrillary tangles."

"excitotoxicity"

A form of neuronal death caused by over-stimulation of glutamate receptors, leading to excessive calcium entry and activation of destructive intracellular enzymes

"Following ischaemic stroke, the failure of energy-dependent glutamate transporters causes massive excitotoxicity in the penumbra surrounding the core infarct."

"demyelination"

The loss or destruction of the myelin sheath surrounding axons, which slows or blocks nerve conduction, as seen most prominently in multiple sclerosis

"MRI revealed multiple periventricular demyelination plaques, a pattern highly characteristic of relapsing-remitting multiple sclerosis."

"seizure threshold"

The level of neuronal excitability above which a seizure is triggered; factors such as sleep deprivation, fever, and genetic mutations can lower the seizure threshold

"Anti-seizure medications act by raising the seizure threshold through mechanisms including sodium channel blockade and enhancement of GABAergic inhibition."

"blood-brain barrier"

A selective permeability barrier formed by tight junctions between cerebral endothelial cells that restricts the passage of substances from the blood into the brain

"Disruption of the blood-brain barrier during neuroinflammation allows peripheral immune cells and potentially neurotoxic proteins to enter the central nervous system."

"neuroinflammation"

An inflammatory response in the central nervous system mediated by activated microglia and astrocytes, which can be protective in the short term but contributes to neurodegeneration when chronic

"PET imaging with a TSPO ligand demonstrated widespread neuroinflammation in the temporal and parietal lobes of patients with mild Alzheimer's pathology."

"tau pathology"

The abnormal hyperphosphorylation and aggregation of the microtubule-associated protein tau into neurofibrillary tangles, which disrupts axonal transport and is a key driver of neurodegeneration in tauopathies

"Post-mortem staging of tau pathology according to Braak criteria revealed that tau spread follows a predictable spatiotemporal pattern starting in the entorhinal cortex."

"dopamine hypothesis"

The proposal that the positive symptoms of schizophrenia result from excessive dopaminergic activity in the mesolimbic pathway, supported by the efficacy of D2-receptor antagonists

"The dopamine hypothesis of schizophrenia gained early support from observations that all effective antipsychotics share the property of blocking D2 dopamine receptors."