A pathophysiology diagram illustrating theoretical models of phantom limb pain (PLP) through cortical reorganization. The image displays a coronal cross-section of the brain, comparing a 'Healthy side' and an 'Affected side' (post-amputation). On the healthy side, stimulation of the lip correctly activates the face representation in the primary somatosensory area (S1), while motor programming activates the hand representation in the primary motor area. On the affected side, functional reorganization is shown where lip stimulation erroneously activates both the face and the amputated hand's S1 representation. This mismatch is labeled as a 'Prediction error,' leading to the perception of 'Pain.' Three theoretical pathways are identified: (A) Maladaptive plasticity, where neural activation directly involves nociceptive neurons; (B) Persistent pain representation, involving motor-to-S1 feedback; and (C) Predictive coding, where the system attempts 'Error reduction' through increased salience, disinhibition, and attempts to adjust expectations. This schematic serves as a medical educational tool for understanding neuroplasticity and the sensory-motor incongruency underlying neuropathic pain syndromes.

This medical illustration depicts a human brain highlighting the primary somatosensory cortex (S1) and its functional connections within the context of cortical remapping and phantom limb pain. The S1 area is highlighted in purple along the postcentral gyrus. The diagram uses arrows to illustrate the complex interplay between anatomical structures and psychological/behavioral drivers. Key cortical areas shown include the primary motor cortex (M1), supplementary motor area (SMA), secondary somatosensory cortex (SII), and posterior parietal cortex (PPC). Subcortical and limbic structures such as the Thalamus, Amygdala, Hippocampus (Hip), and Periaqueductal Grey (PAG) are also interconnected. Five categorized boxes detail variables influencing S1 organization: 1) Pain-related (acute and chronic); 2) Cognitive (attention, sense of control, memory); 3) Affective (depression, anxiety, stress response); 4) Use-dependent (intact arm or prosthesis use); and 5) Perceptual (body ownership, telescoping, referred sensations). This diagram serves as a conceptual model for neuroplasticity and the multi-factorial nature of chronic pain syndromes.

This diagnostic neuroimaging figure displays individual and group-level regions of interest (ROIs) mapped onto a 3D MNI152 brain template, focusing on the primary motor cortex (M1, Panel A) and primary somatosensory cortex (S1, Panel B). The visualization compares three experimental groups: Phantom Limb Pain (PLP, red), non-phantom limb pain (nonPLP, blue), and healthy controls (green). Copper-colored surface masks highlight cortical areas defined by the Juelich atlas. Small colored spheres represent peak coordinates for individual subjects, while spheres with black contours indicate the mean group ROI. A specific 'ROIconj' (conjunction ROI) is identified as the area where control activations overlap. Double-headed arrows with numerical values quantify cortical distances in millimeters (mm) between mean ROIs and the conjunction area. The image illustrates cortical reorganization and spatial shifts in neural activity within the sensorimotor cortex associated with amputation and chronic phantom limb pain, serving as a study of functional neuroanatomy and maladaptive plasticity.

This diagnostic anatomical diagram displays a 3D cortical parcellation of the human brain based on the Desikan-Killiany atlas. The image features two views: a lateral view of the left hemisphere (left) and a medial view of the right hemisphere (right). Various cortical regions are color-coded to delineate functional areas involved in pain processing and connectivity analyses. In the lateral view, the primary somatosensory cortex (SI) is highlighted in red along the postcentral gyrus, the secondary somatosensory cortex (SII) is shown in blue-violet within the parietal operculum, and the insular cortex (Ins) is visible in yellow. The lateral occipital area (LO) is also indicated in deep blue. In the medial view, the anterior cingulate cortex (ACC) is depicted in teal, the posterior cingulate cortex (PCC) in light pink/green, the precuneus (Pre) in lavender, and the fusiform gyrus (Fu) in light green. This visualization serves as a neuroimaging template for mapping regional current density and connectivity in clinical research, specifically for studying the 'pain matrix' and its correlation with subjective pain scales like the Visual Analogue Scale (VAS).