1/7/2024 0 Comments Example of social amnesiaPropofol is an archetypal amnestic drug-it permits robust encoding of material, but the information undergoes accelerated decay because of a failure of consolidation. The drugs are characterized by marked differences in the way they modulate the two coefficients. ![]() Where λ reflects the initial memory strength (an index of encoding), and ψ expresses the rate of decay (an index of consolidation). ![]() However, patients do appear to benefit substantially more from cueing than do other amnesic groups, suggesting that impaired retrieval efficiency contributes to both the anterograde and retrograde aspects of their amnesia. Retrograde memory is nearly always impaired in amnesia secondary to ACoA aneurysm, and it invariably shows a temporal gradient. Another executive contribution to the disorder is the tendency of some ACoA patients to score many false positives on recognition tasks, a finding that suggests an additional impairment in the ability to monitor the outcome of a memory search. This recall–recognition disparity is attributed to the frontal executive component of the amnesia that follows ACoA aneurysm, particularly the disruption of strategic effortful search processes that give access to information stored in memory. Another difference is found in the performance of ACoA patients on recognition tasks, where they are found to succeed more often than their medial temporal lobe counterparts. As a result, ACoA patients will benefit from the use of encoding strategies, whereas patients with medial temporal lobe damage will not. However, the deficit in basal forebrain amnesia is due to inefficient encoding and not to the failure of consolidation that characterizes medial temporal amnesia. The severe deficit in recall found in basal forebrain amnesia shares superficial similarities with the anterograde memory impairment that characterizes medial temporal lobe amnesia. Disruption of frontal network systems can occur and may also contribute to the quality of the memory deficit seen in some ACoA aneurysm-related forms of amnesia. Disruption of hippocampal functioning may play a role in the amnesia of at least some patients with ACoA aneurysm because several basal forebrain nuclei contain a large number of cholinergic neurons that innervate the hippocampus as well as large neocortical regions. Basal forebrain amnesia is usually due to damage to the septal nucleus and the subcallosal area. This wide variability reflects the fact that the ACoA perfuses a broad anatomical brain region, all of which is vulnerable in the event of rupture to damage from infarction, either directly or secondary to subarachnoid hemorrhage, vasospasm, or hematoma formation. Such deficits vary from a very mild impairment to a severe amnesic disorder called basal forebrain amnesia. Memory deficits, along with associated behavioral disorders, frequently follow rupture and surgical repair of an ACoA aneurysm. Ginette Lafleche, Mieke Verfaellie, in Encyclopedia of Applied Psychology, 2004 5.2.1 Anterior Communicating Artery Aneurysm Individuals providing sedation and anesthesia for children must be able to detect and support cardiorespiratory insufficiency. ![]() As sedation deepens toward general anesthesia, loss of airway patency, loss of airway-protective reflexes, and loss of cardiovascular stability occur. Respiratory depression and hemodynamic compromise may be profound. Deep sedation occurs when cardiorespiratory reflexes are obtunded or lost. Light (minimal) sedation is anxiolysis with minimally reduced reflexes or airway patency. Cardiorespiratory reflexes ( airway-protective and vasomotor reflexes) are reduced with general anesthesia. General anesthesia is characterized by unconsciousness, amnesia, and reduced physiologic reflexes. Sedation describes a medically induced state in the continuum between wakefulness and general anesthesia (see Table 74.7). It is also possible to provide analgesia (local, spinal, or epidural) without altering consciousness. However, it is important to remember that sedative-hypnotic agents may alter consciousness without producing analgesia analgesia and hypnosis are not synonymous. Many drugs provide anxiolysis and amnesia for such events ( Table 74.8). A primary goal of anesthetic management is to minimize fear and anxiety during both painful and nonpainful procedures. ![]() Awareness during procedures may be as physically and psychologically deleterious as the experience of pain. The attenuation of both consciousness (hypnosis) and conscious recall ( amnesia) is critical during pediatric anesthesia care. Kliegman MD, in Nelson Textbook of Pediatrics, 2020 Hypnosis and Amnesia
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |