Bisby, J.A. (2011) Acute effects of alcohol on trauma memories. Doctoral thesis, UCL (University College London).
|PDF - Access restricted until 01 August 2013 - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader|
Memory disturbances following a trauma are a characteristic feature of posttraumatic stress disorder. Despite alcohol’s frequent involvement in real-life traumatic events, our understanding of its contribution to trauma-related symptoms is unclear. The research in this thesis aimed to determine the way in which alcohol intoxication during a traumatic experience might influence memory for the event. Experiment 1 showed that alcohol impaired recognition associated with recollection with greater reductions as dose increased (0, 0.4, 0.6, 0.8g/kg); in contrast, recognition associated with familiarity was preserved. Experiments 2 and 3 utilised an analogue trauma film to examine how low (0.4g\kg) and high (0.8g/kg) doses of alcohol affected intrusive imagery and explicit memory for the footage. Alcohol during encoding resulted in a dose-dependent inverted U-shaped curve on intrusive imagery, with increased intrusions only following a low dose. Explicit memory for the footage was reduced in a dose-dependent linear manner. In addition, experiment 3 concurrently assessed same- and shifted-view object location recognition to determine the mechanisms that might underpin alcohol’s effects on trauma memory. Results showed that a low dose of alcohol selectively impaired shifted-view recognition, thought to rely on an allocentric representation. However, same-view recognition was preserved, suggesting a spared egocentric representational system. In contrast, the high dose disrupted both same- and shifted-view recognition, suggesting a global disruption in both memory systems. Experiment 4 examined the effects of alcohol (0.4/kg) on contextual fear acquisition and extinction and both same- and shifted-view recognition. Fear acquisition was unaffected by alcohol, whilst extinction learning was impaired with persistent conditioned responses throughout extinction. Alcohol-induced reductions in extinction learning were highly correlated with decreases in shifted-view recognition, supporting the role of contextual encoding in extinction. The findings of these studies suggest that alcohol dose-dependently influences trauma memories and this could result in a distinct set of trauma-related symptoms.
|Title:||Acute effects of alcohol on trauma memories|
|UCL classification:||UCL > School of Life and Medical Sciences > Faculty of Brain Sciences > Psychology and Language Sciences (Division of) > Clinical, Educational and Health Psychology|
View download statistics for this item
Activity - last month
Activity - last 12 months
Archive Staff Only: edit this record