#parietal lobe

• Acalculia — A clinical neurological or neuropsychological deficit characterized by the acquired loss of the ability to perform simple arithmetic operations or to understand fundamental mathematical concepts, typically occurring due to an organic brain injury (usually affecting the left parietal lobe). Unlike dyscalculia, which is a congenital developmental disorder, achalusia represents a cognitive impairment secondary to trauma, stroke, or neurodegenerative processes.
• Allocheiria — A rare neurological disorder of sensory perception in which a tactile stimulus applied to one side of the body (usually a limb) is erroneously felt or localized by the patient at the symmetrical point on the opposite side. This structural phenomenon occurs most frequently following lesions of the right parietal lobe or in cases of hemispatial neglect syndrome, reflecting a dysfunction in brain somatic map processing.
• Allocheiria — A graphic and clinical variant of the term 'allocheiria'; it represents a neurological disorder of somatic sensitivity where a patient localizes a tactile, thermal, or painful stimulus on the opposite side of where it was actually applied. This structural phenomenon reflects a severe dysfunction in signal transmission and processing within the secondary somatosensory cortex or the parietal lobe, often associated with hemispatial neglect.
• Anomalesia — A rare sensory perception disorder characterized by a partial inability or congenital weakening of tactile and thermal sensitivity, often manifested through difficulties in correctly locating or differentiating physical stimuli applied to the skin. This structural deficit in innervation or central somatosensory processing is studied in clinical neurology in close connection with focal cortical lesions in the parietal lobe.
• Anosognosia — A severe neurological cognitive disorder characterized by a patient's total or partial inability to be aware of or recognize their own illness, functional deficit, or paralysis (such as hemiplegia). This structural phenomenon typically occurs following acute lesions of the right parietal lobe of the brain (caused by strokes or tumors), leading the patient to firmly maintain they are completely healthy despite clinical evidence.
• Apractognosia — A complex neuropsychological syndrome characterized by the coexistence of apraxia (the inability to execute coordinated and intentional movements) and agnosia (the inability to recognize sensory stimuli, objects, or spatial patterns), despite intact elementary motor and sensory functions. This structural phenomenon is usually caused by focal lesions located in the non-dominant (right) parietal lobe of the cerebral cortex, severely affecting spatial orientation and body schemas.
• Asomatognosia — A structural neurological and body schema disorder characterized by a patient's inability to recognize, identify, or perceive a part of their own body or the entire body as belonging to them; this clinical phenomenon is usually caused by focal lesions localized in the right parietal lobe of the non-dominant cerebral hemisphere and often manifests within unilateral spatial neglect syndrome.
• Astereognosis — A rare neurological symptom characterized by an individual's pathological inability to recognize, identify, or differentiate the shape, size, weight, and nature of an object exclusively through tactile exploration (without the aid of vision or hearing), despite basic peripheral tactile sensitivity in the hand remaining fully intact; it is caused by brain lesions located in the parietal lobe.
• Atopognosia — A neurological symptom characterized by an individual's loss of ability to correctly localize tactile stimuli applied to the body surface; the impossibility to recognize the exact place of a touch. This sensory spatial perception disorder is usually caused by a structural lesion located within the parietal lobe of the cerebral cortex.