Biomedical subjects

Martin A Conway

Publications and source records attributed to Martin A Conway.

11 recordsLinked to original sources

PubMed2006

Episodic inhibition.

Six experiments examined the proposal that an item of long-term knowledge can be simultaneously inhibited and activated. In 2 directed forgetting experiments items to-be-forgotten were found to be inhibited in list-cued recall but activated in lexical decision tasks. In 3 retrieval practice experiments, unpracticed items from practiced categories were found to be inhibited in category-cued recall but were primed in lexical decision. If, however, the primes and targets in lexical decision were taken directly from the study list, inhibition was observed. Finally, it was found that when items highly associated with a study list were processed in between study and test, no inhibition in recall was present. These, and a broad range of other findings, can be explained by the concept of "episodic inhibition," which proposes that episodic memories retain copies of semantic knowledge structures that preserve patterns of activation/inhibition originally generated in those structures during encoding. ((c) 2006 APA, all rights reserved).

Adolescent↗

PubMed2005

Disordered memory awareness: recollective confabulation in two cases of persistent déjà vecu.

We describe two cases of false recognition in patients with dementia and diffuse temporal lobe pathology who report their memory difficulty as being one of persistent déjà vecu--the sensation that they have lived through the present moment before. On a number of recognition tasks, the patients were found to have high levels of false positives. They also made a large number of guess responses but otherwise appeared metacognitively intact. Informal reports suggested that the episodes of déjà vecu were characterised by sensations similar to those present when the past is recollectively experienced in normal remembering. Two further experiments found that both patients had high levels of recollective experience for items they falsely recognized. Most strikingly, they were likely to recollectively experience incorrectly recognised low frequency words, suggesting that their false recognition was not driven by familiarity processes or vague sensations of having encountered events and stimuli before. Importantly, both patients made reasonable justifications for their false recognitions both in the experiments and in their everyday lives and these we term 'recollective confabulation'. Thus, the patients are characterised by false recognition, overextended recollective experience, and recollective confabulation. These features are accounted for in terms of disrupted control of memory awareness and recollective states, possibly following brain damage to fronto-temporal circuits and we extend this account to normally and abnormally occurring states of déjà vu and vecu and related memory experiences.

Aged↗

PubMed2004

Images and goals.

We propose that mental images are derived from goals. Goals are represented in a complex hierarchy and form a major part of the "working self". Images reflect the existence of specific goals and also act to maintain goals by facilitating the derivation of beliefs from the content of an image. Images in psychopathology may reflect the operation of dysfunctional goals: goals that are unconstrained and which increase discrepancy (experienced as anxiety) within the goal system. Another feature of the goal system is that it is conservative and avoids change. By this view some aspects of distortions in intrusive images of traumatic experiences might be viewed as a defence against goal change. Conversely generating new images might lead to the formation of new goals. These ideas are applied to the findings of the papers in this special issue of Memory and to several new case studies.

Adaptation, Psychological↗

PubMed2004

Psychosocial stages and the accessibility of autobiographical memories across the life cycle.

Older adults recalled memories from each decade of life. Memories were classified in terms of the psychosocial stages to which their content corresponded. For the majority of memories it was found that age at encoding corresponded to when specific psychosocial stages would have been most likely to have occurred. In a second experiment older adults recalled memories to cues drawn from psychosocial stages and the same pattern of findings was observed. These findings demonstrate that the goals of the self play a major role in both the encoding and accessibility of autobiographical memories, and they also provide support for Erikson's psychosocial theory of development (1950, 1997).

Aged↗

PubMed2004

The stories we keep: autobiographical memory in American and Chinese middle-aged adults.

One hundred and eight European American and Chinese adults, aged between 38 and 60, participated in this questionnaire study. They each recalled 20 memories from any period of their lives. Memory content was analyzed as a function of culture (U.S. and China), life period (childhood, youth, early midlife, and peak midlife), and gender (female and male). Across the four life periods, Americans provided more memories of individual experiences and unique, one-time events and focused on their own roles and emotions. In contrast, Chinese were more inclined to recall memories of social and historical events and placed a great emphasis on social interactions and significant others in their memory narratives. Chinese also more frequently drew upon past events to convey moral messages than did Americans. In addition, memory content evidenced age-related increases in both autonomous and social orientations. Findings are discussed in light of the self-definitional and directive functions of Autobiographical memory in the context of culture.

Adult↗

PubMed2003

Neurophysiological correlates of memory for experienced and imagined events.

Changes in slow cortical potentials within EEG were monitored while autobiographical memories of experienced and imagined event were generated and then held in mind for a short period. The generation of both kinds of memory led to significantly larger negative dc shifts over left versus right frontal regions, and this was interpreted as a reflection of substantial left frontal activation. The generation phase was also associated with greater right versus left negative dc shifts over posterior occipital regions. This pattern replicates and extends previous findings from our laboratory. In addition, however, experienced memories were associated with significantly larger negative dc shifts over occipito-temporal regions than imagined events. Furthermore, during the hold-in-mind period, imagined events led to larger negative dc shifts over left frontal regions than experienced events. These findings suggest that memories for imagined and experienced events may share control processes that mediate construction of memories but that they differ in the types of content of the memories: memories of experienced events contain sensory-perceptual episodic knowledge stored in occipital networks whereas memories for imagined events contain generic imagery generated from frontal networks.

Adult↗

PubMed2003

Commentary: cognitive-affective mechanisms and processes in autobiographical memory.

This commentary highlights some of the interesting points to emerge from the preceding papers about the self, social, and directive functions of autobiographical memory. Additionally some cognitive functions are also considered and especially the way in which autobiographical memory supports, constrains, and maintains the goals of the self. Directions for future research into the self, social, directive, and cognitive-affective functions and processes of autobiographical memory are reviewed. Emphasis is placed on future research into the function of autobiographical memory in representations of attachment.

Behavior↗

PubMed2003

Themes, events, and episodes in autobiographical memory.

The process by which experience is divided into events was examined. Experiment 1 involved diarists recording their experiences over a 3-month period. Diary entries were later transcribed onto cards and the diarists arranged their cards so as to define events they had experienced, and in a separate phase arranged their cards so as to describe the themes that reflected their life. Examination of event- and theme-building strategies indicated that boundaries were frequently used, and events and themes were often formed from clusters of experience combined using content association rather than temporal sequence. Experiment 2 involved photographs taken by the participants, employed the same procedures as in Experiment 1, and revealed event- and theme-building strategies similar to those identified in Experiment 1. In Experiment 3 the size of the stimulus set from which events and themes were constructed was manipulated; this did not influence construction strategies. Overall, the experiments show that both autobiographical events and themes frequently consist of episodes taken from more than 1 day.

Autobiographies as Topic↗

PubMed2002

Retrieval-induced forgetting in Alzheimer's disease.

It is claimed that Alzheimer's disease (AD) patients show reduced inhibitory processing and this has been put forward as a reason why AD patients make intrusion errors at recall. However, the evidence to date has been equivocal, because non-inhibitory mechanisms can account for the pattern of findings. Recently, however, a paradigm has been developed that is claimed to give a purer measure of inhibitory processing in episodic memory, the retrieval-induced forgetting (RIF) paradigm [Inhibitory Processes in Attention, Memory and Language, Academic Press, San Diego, 1994, p. 265; J. Exp. Psychol.: Learning, Memory Cognition 20 (1994) 1063; Psychol. Rev. 102 (1995) 68]. Thus, we were interested whether AD patients would show a deficit in inhibitory processing using this procedure. Participants studied lists of category cue-exemplar pairs (e.g. fruit-orange) then practised retrieval for a subset of items from a subset of categories before taking a final memory test for all studied items. As in previous work, inhibition was measured as the difference between final memory performance for unpractised items from practised categories, and unpractised items from unpractised categories. The results show that AD patients showed normal levels of inhibition with both tests of cued recall and category generation (CG). This suggests that a deficit in inhibitory processes during retrieval is not behind the high levels of intrusion errors made in recall in AD.

Aged↗

PubMed2002

Assessing the inhibitory account of retrieval-induced forgetting with implicit-memory tests.

Five experiments examined whether retrieval-induced-forgetting effects are observed for implicit tests of memory. In each experiment participants first studied category-exemplar paired associates, then practiced retrieval for a subset of items from a subset of categories before finally completing memory tests for all the studied items. In standard fashion, inhibition was measured as the performance difference of unpracticed items from practiced categories and unpracticed items from unpracticed categories. Across the 5 experiments poorer performance for unpracticed items was seen in conceptual implicit memory (category generation and category matching) but not in perceptual implicit memory (stem completion, perceptual identification). Thus, retrieval-induced-forgetting effects are limited to tests of conceptual memory.

Adult↗

PubMedDate not supplied

Disruption of inhibitory control of memory following lesions to the frontal and temporal lobes.

A group of patients with lesions to the frontal lobes, a group with lesions to the temporal lobes, and groups of non-brain damaged controls took part in three experiments. The first experiment used directed forgetting (DF) by items, the second DF by lists, and the third retrieval induced forgetting (RIF). Frontal patients with right side lesions could not intentionally inhibit but all frontal patients showed normal RIF. Temporal patients with left side lesions had abnormal DF by lists and all the temporal patients had abnormal RIF. These findings are explained in terms of impairment to executive thought avoidance control processes in frontal patients and impaired knowledge access to long-term memory in temporal patients.

Adult↗