1,240 articles
tFUS trial
A tFUS trial is a clinical study of transcranial focused ultrasound, which delivers low-intensity ultrasound pulses through the skull to stimulate the thalamus in disorders of consciousness.
Thalamotomy
Thalamotomy: neurosurgical ablation of the thalamic ventral intermediate (Vim) nucleus to treat medication-refractory tremor in essential tremor and tremor-dominant Parkinson's disease, performed by radiofrequency, radiosurgery, or MR-guided focused ultrasound.
Thalamus
Thalamus: paired ovoid gray-matter nuclei at the top of the brainstem relaying all sensory information except smell to cortex; also gates consciousness, sleep rhythms, cognition, and is a target for DBS in tremor and epilepsy.
The Behavioral and brain sciences
Behavioral and Brain Sciences (BBS), Cambridge University Press journal founded 1978 by Stevan Harnad, known for Open Peer Commentary: target articles co-published with 20–40 invited cross-disciplinary commentaries and the author's response.
The Brain Prize
The Brain Prize is an annual award of DKK 10 million, about €1.3 million, given by Denmark's Lundbeck Foundation since 2011 to brain researchers of any nationality.
The Lancet. Neurology
The Lancet. Neurology (Lancet Neurol), monthly Elsevier neurology journal launched May 2002, ISSN 1474-4422; edited by Elena Becker-Barroso since 2012; 2025 impact factor 54.6, ranked first among clinical neurology journals.
Thecal sac
Thecal sac (dural sac, saccus durae matris spinalis): the dural sheath in the spinal canal enclosing the spinal cord, cauda equina, and cerebrospinal fluid; key MRI stenosis marker, lumbar puncture target, and SBRT contour.
Theta wave
Theta wave (theta rhythm): a 4–8 Hz brain oscillation, first seen in rabbit hippocampus (Jung and Kornmüller, 1938), prominent during rodent movement, REM sleep, human drowsiness, and frontal-midline cognitive processing, linked to navigation, memory, and phase precession.
Thiel-Behnke corneal dystrophy
Thiel-Behnke corneal dystrophy (TBCD, honeycomb corneal dystrophy, CDB2) is a rare autosomal dominant TGFBI (5q31, Arg555Gln) corneal dystrophy causing recurrent erosions, honeycomb subepithelial opacities, and progressive vision loss, treated with PTK.
Thoracic outlet syndrome due to cervical rib
Thoracic outlet syndrome due to cervical rib (ICD-11 8B91.1): neurovascular compression at the thoracic outlet caused by an extra rib from C7, found in 1.1% of healthy people but 29.5% of TOS patients.
Thygeson superficial punctate keratitis
Thygeson superficial punctate keratitis (TSPK), also called Thygeson's superficial punctate keratopathy, is a rare chronic bilateral corneal epitheliopathy with recurrent gray-white intraepithelial opacities, unknown cause, HLA-DR3 association, and corticosteroid-responsive flares.
Tibial nerve
Tibial nerve: terminal branch of the sciatic nerve (L4–S3) supplying motor and sensory innervation to the posterior leg and plantar foot; passes through the tarsal tunnel, dividing into medial and lateral plantar nerves; tarsal tunnel syndrome is its main entrapment.
Tickling
Tickling: touching the body to provoke laughter or squirming, divided into knismesis (light, feather-like) and gargalesis (heavy, laughter-inducing); self-tickle is suppressed by cerebellar prediction, and rats and great apes are ticklish too.
Timrepigene emparvovec
Timrepigene emparvovec (BIIB111, AAV2-REP1) is an investigational AAV2 subretinal gene therapy delivering the CHM/REP1 gene for choroideremia; its phase 3 STAR trial missed the ≥15-letter BCVA endpoint but showed more ≥10-letter gains than controls.
Tinnitus
Tinnitus: perception of sound without an external source (ringing, buzzing, roaring), also called tinnitus aurium. Affects 10-25% of adults; linked to hearing loss, noise exposure, and medications; no FDA-approved drug treatment.
Total external ophthalmoplegia
Total external ophthalmoplegia (ICD-10 H49.3) is complete paralysis of the extraocular muscles with ptosis; acute causes center on Miller Fisher syndrome, chronic causes on mitochondrial CPEO.
Touch
Touch (tactile sense, taction): the sensation of physical contact with objects, detected by mechanoreceptors in skin and mucous membranes; includes discriminative and affective (C-tactile) systems, haptics, and the somatosensory homunculus.
Toxoplasmic chorioretinitis
Toxoplasmic chorioretinitis (ocular toxoplasmosis, toxoplasma retinochoroiditis) is recurring Toxoplasma gondii inflammation of retina and choroid, a leading cause of posterior uveitis; antibiotics reduce recurrences but visual benefit is unproven.
Trabeculectomy
Trabeculectomy is a glaucoma operation that creates a small drainage channel in the eye to lower intraocular pressure, and is often described as the gold standard.
Trachoma
Trachoma, caused by Chlamydia trachomatis, is the leading infectious cause of blindness; controlled by the WHO SAFE strategy, with 33 countries validated as having eliminated it as a public health problem by 2026.
Tragus (ear)
Tragus (ear): the small cartilaginous fold of the auricle in front of the ear canal opening. First-arch derivative per classical and revised embryology; tragal pointer marks the facial nerve; common cartilage piercing site.
Transcranial direct-current stimulation
Transcranial direct-current stimulation (tDCS) is a non-invasive brain stimulation method delivering 1–2 mA constant current via scalp electrodes; used for depression (Level A evidence), pain, stroke, and Parkinson's disease, with HD-tDCS variants.
Transcranial Doppler
Transcranial Doppler (TCD) ultrasonography, introduced by Aaslid in 1982, is a noninvasive 2 MHz ultrasound test measuring blood flow velocity in basal brain arteries, used for vasospasm, stroke, sickle cell screening, and brain death confirmation.
Transcranial magnetic stimulation
Transcranial magnetic stimulation (TMS, rTMS) is a noninvasive brain stimulation technique introduced by Barker in 1985, using pulsed magnetic fields to depolarize cortical neurons; FDA-cleared for depression, OCD, and migraine, with seizure risk under 0.1%.
Traumatic brain injury
Traumatic brain injury (TBI), also called concussion in its mild form, is brain dysfunction from a bump, blow, jolt, or penetrating head injury; classified by Glasgow Coma Scale as mild, moderate, or severe, causing about 69 million injuries yearly.
Traumatic cerebral oedema
Traumatic cerebral oedema (ICD-11 NA07.2) is fluid accumulation in brain tissue after traumatic brain injury, occurring in over 60% of mass-lesion cases. Subtypes include cytotoxic, vasogenic, and ionic edema; treatment uses hyperosmolar therapy, CSF drainage, and decompressive craniectomy, with corticosteroids contraindicated.
Traumatic intracerebral haemorrhage
Traumatic intracerebral haemorrhage (TICH, ICD-11 NA07.1) is brain parenchymal bleeding caused by external head trauma, distinct from spontaneous ICH; it affects younger patients and carries a much better prognosis (67% vs 24% favorable outcomes).
TraVi_II study
TraVi_II (TraVi II), NCT06776107, is a retrospective cross-sectional study of factors associated with ICU mortality in 80 traumatic brain injury patients at Hospital Departamental de Villavicencio, Colombia, 2019-2024; no results posted.
Trichiasis without entropion
Trichiasis without entropion (ICD-11 9A04.0) is misdirected eyelashes touching the cornea or conjunctiva with a normal lid margin position. Causes include blepharitis, trachoma, and burns; treated by epilation, electrolysis, laser, or surgery.
Trichromacy
Trichromacy: normal human color vision based on three cone classes (L, M, S) such that any color can be matched with three primaries; foundation of colorimetry, distinct from dichromacy and tetrachromacy.