This medical anatomical diagram illustrates a transverse section of the human spinal cord, specifically detailing the organization of white matter tracts. The visual uses a color-coded schema to differentiate between motor and sensory pathways: descending (efferent) motor tracts are highlighted in red, while ascending (afferent) sensory tracts are shown in blue. Key anatomical structures identified include the Pyramidal tracts (lateral and anterior corticospinal tracts), Extrapyramidal tracts (rubrospinal, reticulospinal, olivospinal, and vestibulospinal), the Dorsal Column-Medial Lemniscus system (gracile and cuneate fasciculi), Spinocerebellar tracts, and the Anterolateral system (lateral and anterior spinothalamic tracts). A significant educational feature of the diagram is the depiction of somatotopic organization, showing the concentric arrangement of sacral, lumbar, thoracic, and cervical fibers within the lateral corticospinal and dorsal column tracts. The image provides a comprehensive overview of spinal cord neuroanatomy, useful for understanding clinical localization of spinal cord lesions and the functional topography of the central nervous system.

An educational pathophysiology diagram illustrating the pathways of peripheral and central neural sensitization in chronic itch. The diagram traces signals from the skin, through the spinal cord, to the brain. Primary cutaneous stimuli include inflammation (NGF, PGE2) and abnormal innervation via PAR-2 activation. Pruritic signals travel through the dorsal root ganglion (DRG), where upregulation of Substance P and BDNF occurs, and enter the spinal cord. The spinal level highlights dysregulation of itch-inhibitory circuits involving Bhlhb5-positive (chemical itch) and NPY-positive (mechanical itch) neurons. Ascending transmission via the spinothalamic and spinoparabrachial tracts carries signals to the brain, specifically the periaqueductal gray (PAG) and parabrachial nucleus (PBN). The diagram depicts increased neural activity and structural/functional changes (gray matter volume, connectivity) in cortical regions including the prefrontal cortex (PF) and anterior cingulate cortex (ACC). A descending inhibitory pathway from the PAG to the spinal cord is also shown, noting altered supraspinal inhibitory signals that contribute to the chronic itch cycle.

This composite educational image illustrates the radiological and pathophysiological features of Central Cord Syndrome. Panels A, B, and C present three sequential cranial-to-caudal axial T2-weighted MRI scans of the cervical spine at the C2-3 level. These images reveal a focal area of hyperintensity (high signal) localized in the central portion of the spinal cord, corresponding to the central canal and surrounding gray matter. Panel D is a neuroanatomical schematic diagram illustrating the lateral spinothalamic tracts across C2, C8, and T4 spinal levels. A blue circle highlights a central lesion at the C2 level, specifically demonstrating how the injury interrupts the decussating fibers of the spinothalamic tract as they cross the anterior white commissure. This visual correlation explains the mechanism of bilateral neuropathic pain and sensory deficits localized to the dermatome level of the injury (C2) while sparing more laterally located ascending tracts. The content serves to teach the clinical-radiological correlation of traumatic spinal cord injuries and the functional anatomy of sensory pathways within the spinal cord.

This medical anatomical diagram illustrates the cross-sectional neuroanatomy and white matter tract localization within the mouse spinal cord at four distinct levels: Cervical (C8), Thoracic (T7), Lumbar (L3), and Sacral (S2). Each level depicts the characteristic morphology of the spinal cord, showing the transition from a rounded C8/T7 shape to a more laterally expanded L3 and a flattened, compressed S2. Key ascending (sensory) and descending (motor) pathways are highlighted in blue. Notable structures include the dorsal corticospinal tract (dcs) located centrally along the dorsal midline, flanked by the gracile fasciculus (gr) and cuneate fasciculus (cu, prominent in higher levels). Lateral tracts shown include the rubrospinal (rs), dorsal spinocerebellar (dsc), and lateral spinothalamic (lst) tracts. Ventral regions display the vestibulospinal (lvs, mvs) and reticulospinal (crts, rrts) tracts. The diagrams also delineate Rexed laminae (1Sp-10Sp) within the gray matter and the central canal (CC). This educational resource is designed for neuroanatomical mapping and comparative spinal pathology research.

A pathophysiology diagram illustrating the ascending sensory pathways from the periphery to the cerebral cortex. The schematic uses a coronal section of the human brain, brainstem, and spinal cord to trace three major systems: the auditory-lateral lemniscal system (solid orange line), the dorsal column-medial lemniscus system (solid black line), and the anterolateral system (dashed black line). The auditory pathway is traced from the ear through the auditive nerve, cochlear nucleus, superior olivary complex, lateral lemniscus, and inferior colliculus, relaying through the medial geniculate nucleus of the thalamus to the auditory cortex. Somatosensory pathways are traced from receptor endings in the finger through the dorsal root ganglion to the spinal cord. The dorsal column system ascends ipsilaterally before decussating in the medulla (medial lemniscus) and relaying via the thalamus to the somatosensory cortex. The anterolateral system decussates at the spinal level before ascending. This visual summarizes the functional neuroanatomy required for sensory reactivity, commonly assessed in electroencephalography (EEG) clinical evaluations.

Educational neuroanatomical diagram and MRI composite illustrating the dorsal column-medial lemniscus (DCML) system. The visual uses a side-by-side comparison of ex vivo (left) and in vivo (right) high-resolution 7-T MR images to trace the somatosensory pathway. Red lines represent the trajectory of second-order neurons from the brainstem to the thalamus. Key structures are color-coded: the gracile and cuneate fasciculi are highlighted in orange at the caudal medulla; the gracile and cuneate nuclei are in green, marking the site of first-order synapse. The internal arcuate fibers are shown decussating before forming the medial lemniscus, which is highlighted in yellow across axial slices of the medulla, pons, and midbrain. Yellow arrows in the oblique sagittal and coronal brainstem views indicate the ascending trajectory of the medial lemniscus. The pathway terminates at the ventral posterolateral (VPL) nucleus of the thalamus, highlighted in green on coronal sections. This infographic serves as a diagnostic and anatomical reference for tracing epicritic sensation and conscious proprioception pathways.