Eva Svoboda

Aging and autobiographical memory: dissociating episodic from semantic retrieval.

Cognitive aging research documents reduced access to contextually specific episodic details inolder adults, whereas access to semantic or other nonepisodic information is preserved or facilitated. The present study extended this finding to autobiographical memory by using a new measure; the Autobiographical Interview. Younger and older adults recalled events from 5 life periods. Protocols were scored according to a reliable system for categorizing episodic and nonepisodic information. Whereas younger adults were biased toward episodic details reflecting happenings, locations, perceptions, and thoughts, older adults favored semantic details not connected to a particular time and place. This pattern persisted after additional structured probing for contextual details. The Autobiographical Interview is a useful instrument for quantifying episodic and semantic contributions to personal remote memory.

Compensating for anterograde amnesia: A new training method that capitalizes on emerging smartphone technologies

Following a neuropathological event, individuals left with moderate-to-severe memory impairment are unable to reliably form new memories. The most common challenges involve the capacity to perform a task in the future and to consciously recall a recent event. Disruption of these memory processes leaves the individual trapped in the present, unable to stay on track, and alienated from ongoing events. Memory research has demonstrated that implicit memory is often preserved despite severe explicit memory impairment and that preserved memory systems can provide avenues for acquiring new skills and knowledge. A within-subject single-case A1-B1-A2-B2 experimental design was used to introduce an established theory-driven training program of technology use for individuals with moderate-to-severe memory impairment. We describe its application to enabling RR, an individual with memory impairment postcolloid cyst removal, to independently support her memory using a commercial smartphone. RR showed successful outcome on both objective and qualitative measures of memory functioning. Moreover, she demonstrated consistent and creative generalization of acquired smartphone skills across a broad range of real-life memory-demanding circumstances. Our findings suggest that individuals with moderate-to-severe memory impairment are able to capitalize on emerging commercial technology to support their memory.

The Effects of Rehearsal on the Functional Neuroanatomy of Episodic Autobiographical and Semantic Remembering: A Functional Magnetic Resonance Imaging Study

This study examined the effects of rehearsal on the neural substrates supporting episodic autobiographical and semantic memory. Stimuli were collected prospectively using audio recordings, thereby bringing under experimental control ecologically valid, naturalistic autobiographical stimuli. Participants documented both autobiographical and semantic stimuli over a period of 6–8 months, followed by a rehearsal manipulation during the 3 d preceding scanning. During functional magnetic resonance imaging scanning, participants were exposed to recordings that they were hearing for the first, second, or eighth time. Rehearsal increased the rated vividness with which information was remembered, particularly for autobiographical events. Neuroimaging findings revealed rehearsal-related suppression of activation in regions supporting episodic autobiographical and semantic memory. Episodic autobiographical and semantic memory produced distinctly different patterns of regional activation that held even after eight repetitions. Region of interest analyses further indicated a functional anatomical dissociation in response to rehearsal and memory conditions. These findings revealed that the hippocampus was specifically engaged by episodic autobiographical memory, whereas both memory conditions engaged the parahippocampal cortex. Our data suggest that, when retrieval cues are potent enough to engage a vivid episodic recollection, the episodic/semantic dissociation within medial temporal lobe structures endure even with multiple stimulus repetitions. These findings support the multiple trace theory, which predicts that the hippocampus is engaged in the retrieval of rich episodic recollection regardless of repeated reactivation such as that occurring with the passage of time.

PDA and smartphone use by individuals with moderate-to-severe memory impairment: Application of a theory-driven training programme

We describe a structured, theory-driven training programme for individuals with moderate-to-severe memory impairment in the use of emerging commercial technology. We demonstrate its application to 10 individuals with memory impairment from a variety of aetiologies. A within-subject, ABAB multi-case experimental design was used to evaluate the impact of personal digital assistant or smartphone use on day-to-day memory functioning at baseline, immediately post-intervention, at return to baseline, and at short-term follow-up (range = 3–8 months). An errorless fading-of-cues protocol enabled all participants to acquire the skill set necessary to operate their PDA or smartphone independently. All 10 individuals showed robust improvement in day-to-day functioning post-intervention as quantified across a number of ecologically valid questionnaire and task-based measures. This was further corroborated by family members with whom six of the participants resided. These findings demonstrate that individuals with moderate-to-severe memory impairment can acquire the skills necessary to independently, flexibly and broadly apply commercial technology to support their everyday memory functioning. Moreover the findings confirm that the gap between individuals with memory impairment and potent emerging technology can be closed by the application of a systematic theory-driven training programme.

A theory-driven training programme in the use of emerging commercial technology: Application to an adolescent with severe memory impairment

We describe a theory-driven memory intervention programme for training individuals with moderate to severe memory impairment in the use of emerging commercial technology. Here we demonstrate the application of the programme to training MK, an 18-year-old woman with severe memory impairment following treatment for a suprasellar germinoma, to autonomously use a smartphone to support her day-to-day memory. A within-subject A1B1A2B2 single-case experimental design was used to evaluate the impact of smartphone use on MKs real-life functioning. Following intervention MK showed increased confidence in dealing with memory-demanding situations and generalised smartphone use across all aspects of her life as quantified by several and varied ecologically valid measures including a phone call schedule, behaviour memory observations and questionnaires. Moreover the intervention also benefited her family as indicated by a sustained reduction in caregiver strain and an increase in reported quality of life. These findings suggest that individuals with severe memory impairment, particularly young adults with potentially life-long dependence on their families, are able to capitalise on emerging commercial technology to function more autonomously. The findings also suggest that the gap between individuals with severe memory impairment and potent emerging technology can be closed by provision of a theory-driven structured training programme.

Hippocampal Complex Contribution to Retention and Retrieval of Recent and Remote Episodic and Semantic Memories: Evidence from Behavioral and Neuroimaging Studies of Healthy and Brain-Damaged People

For over a hundred years, it has been accepted that remote memories are less vulnerable to disruption than are recent memories. The standard consolidation model posits that the hippocampus and related structures are temporary memory structures, necessary for acquisition, retention, and retrieval of all explicit (declarative) memories until they are consolidated elsewhere in the brain. We review lesion and neuroimaging evidence showing that important distinctions exist among different types of explicit memory and the structures that mediate them. We argue that retention and retrieval of detailed, vivid autobiographical memories depend on the hippocampal system no matter how long ago they were acquired. Semantic memories, on the other hand, benefit from hippocampal contribution for some time before they can be retrieved independently of the hippocampus. Even semantic memories, however, can have episodic elements associated with them which continue to depend on the hippocampus. In short, the evidence reviewed suggests strongly that the function of the hippocampus (and possibly of related limbic structures) is to help encode, retain, and retrieve experiences, no matter how long ago the events comprising the experience occurred. We conclude that the evidence favors a multiple trace theory (MTT) of memory over the traditional model, and we indicate what future work is needed to resolve disputes.

Long-term maintenance of smartphone and PDA use in individuals with moderate to severe memory impairment

In an earlier paper we described a structured, theory-driven training programme which was administered to 10 individuals with moderate-to-severe memory impairment. All individuals received an errorless-fading-of-cues protocol in the use of personal digital assistants (PDAs) or smartphones (Svoboda, Richards, Leach, & Mertens, 2012) and demonstrated generalisation of acquired skills to day-to-day memory challenges. Maintenance of intervention gains over the long-term is another indicator of successful generalisation. Here we present the maintenance of device use in the same group of individuals 12 to 19 months after programme completion. A within-subject, ABABB multi-case experimental design was used to evaluate the impact of PDA or smartphone use on day-to-day memory functioning at baseline, immediately post-intervention, at return to baseline, and at short-term and long-term follow-up. Results presented here focus predominantly on long-term follow-up. All 10 individuals showed maintenance of gains in day-to-day functioning as quantified across several ecologically valid questionnaire and task-based measures. This was corroborated by family members with whom six of the participants resided. This study further demonstrates the programmes clinical effectiveness in enabling individuals with moderate-to-severe memory impairment to function more independently and with greater confidence up to 19 months following programme completion.

A case study of topographical disorientation: behavioural intervention for achieving independent navigation

ABSTRACT This study introduces an intervention that enabled a man (LH) with acquired topographical disorientation (TD) to travel independently without fear of getting lost. Adapting an errorless method, LH learned to use a smartphone to find his routes accurately and reliably. A time-series design (A1-B1-A2-B2) was used: In all phases, LH was given a printed map on which city locations were indicated. He had to walk to the indicated locations while naturalistic outcomes were recorded. In Phases A, he navigated without his smartphone, and in Phases B, with it. In Phases A, LH made numerous surplus direction changes, and openly expressed his frustration. In Phases B, he did not have surplus direction changes and could calmly find his routes. Before intervention, LH and his wife were frustrated and worried about his way-finding. They rated their confidence in his navigational ability and his actual ability in way-finding to various locations as low. After intervention, they were more confident that LH could travel by himself without getting lost and rated his ability as much higher for various scenarios. As a consequence of intervention LH gained greater independence and quality of life.