SEARCHING FOR MEMORY. Daniel Schacter, 1996.

INTRODUCTION: Memory's Fragile Power

Introduces the main themes of the book: focus on explicit remembering of episodes from our past; memory is not a passive or literal recording of events, but a subjective reconstruction that reflects an interplay of engram, cue, and the rememberer's current state. "Fragile power" comes from its vulnerability to error and loss, but its pervasiveness in determining who we are. Previews the individual chapters (8-11). Begins examples of art about memory.

1. ON REMEMBERING: A Telescope Pointed at Time

Concerns the subjective aspects of autobiographical memory, describes several cases of "obsessive remembering", and distinguishes "information retrieval", which computers do well, from "remembering", noting how the replicant Rachel convinces Harrison Ford that her memories are "real" by displaying the emotional, subjective reactions of the recollective experience.

Experiencing the Past. After contrasting procedural and semantic memory from episodic "remembering", stresses the role of the rememberer's dual existence in the present and past.

Memory's Point of View. Contrasts memory from your original perspective ("field" memory) and from an outside, omniscient observer ("observer" memory), and the flexibility of taking on each; how it correlates with emotional experiences (more from field, of course).

Remembering and Knowing the Past. Contrasts remember vs know a la Tulving & Gardiner, discusses conditions that lead to greater remembering (visual imagery present; elaborative encoding or attention, and successful retrieval in the absence of explicit cues (24-25). Notes potential errors in feelings of knowing.

The Pull of the Past: Three Stories. Proust's obsession with remembering and constructing his past, and his realization that most will remain unseen (telescope metaphor) without rigorous cuing and searching (26-28); Franco Magnani's visual obsessions with the Italian village of Pontino, and attempts to capture it in painting. Theme of subjective reconstruction here too in spite of apparent recall of detail; paintings as idealizations of his memories. And GR, an artist who after a stroke damaging the left thalamus, had severe retro and anterograde amnesia, followed by a rare, sudden, full recovery of memory during a medical procedure that cues a similar one from his past.

Are Computers Rememberers? Contrasts "strong AI" claims of people like Dennett, who think yes, with those like Gerald Edelman, with whom he sides, that think no, it needs a biological "substrate" and requires the phenomenological experience of remembering.

COMMENTS: Anticipates much of what is to come, with emphasis on "remembering" as an active, vulnerable, and interactive special kind of "memory", in the tradition set down by Tulving - his graduate advisor. Use for discussions of the problems with the "tape recorder" view of memory, with exercises in different accounts of the "same" event? See next chapter too.

2. BUILDING MEMORIES: Encoding and Retrieving the Present and the Past.

A tutorial on encoding specificity, the first part describing how details of encoding and the encoder determine what can later be remembered, and the second part, focussed on the interaction of retrieval cue, current state, and engram (Neisser's "bone fragments") to produce memories.

Bubbles P. And the nature of Encoding. Bubbles is a gambler and digit span expert. Doesn't detail his mnemonics, but uses the example to talk about elaborative and deep encoding to overcome working memory limits; how elaborative encoding occurs naturally for meaningful and important or novel events (45-46); reviews the classic mnemonic devices including Loci, and experts like Chase's SF track times, chess masters, and Rain Man (brief) (47-50). Uses diverse memories of a Magritte painting to talk about what we remember linked to what we think about during encoding, and how two people can have "radically different recollections of the same event." The emphasis is on the diversity of encoding options.

Scanning the Mind. PET work by Craik et al reviewed suggesting left inferior frontal activity during elaborative encoding, and P300 enhancement; and the role of the hippocampus during orienting to novelty.

Historical interlude: The story of Richard Semon. Shifts focus to events and cues at retrieval. Semon was the first to stress the interaction of engram and cue in constructing memory experience, though his work was long neglected. His 1909 book in particular laid this out, and stressed how "potential" memories require the right cue. Introduces encoding specificity, and suggests that elaborative encoding works because of multiple possible cues; but can be overcome by "just the right cue" a la transfer-appropriate ideas. Touches on state-dependence effects, gives examples of his forgetting of being at the Coronado Hotel, and how Magritte can be recalled by very different, but encoding-appropriate, cues (60).

NEIL: Retrieval Processes and the Brain. A case of tumor and chemo damage leading to anterograde amnesia that's severe with oral responses, but bizaarely much better with written responses. DS suggests we don't understand this dissociation, but his point seems to be that retrieval is itself a complex, active process, so even with the same "cue" we may get different memories depending on how the memory is expressed. Notes PET work by Squire and by DS suggesting two different mechanisms, and regions, for "strategic recall" (a la Proust; the frontal esp. Right lobes) and "automatic" associative cued recall (the medial temporal regions, esp hipp and parahipp, interacting with otehr cortical areas).

Constructing memories: the Role of the Retrieval Environment. "The cue combines with the engram to yield..an experience that differs from either of its constituents." And how this helps clarify things liek the field/observer shifts above, and the biasing effects of cue details on memory. Cites his own study of how faint diffs in expression of test faces bias recall of voice tone of studied face (70). Thinks connectionism captures the ecphoric nature of recall, but I'm not convinced.

COMMENTS: Together with the extensive notes, should serve as a reasonable introduction to these themes, esp. for students who haven't had the cognitive class. Emphasis throughout is dynamic and interactive anture of remembering.

3. OF TIME AND AUTOBIOGRAPHY

Theme is of how memory changes over time, and the increasing role of cuing, consolidation and reconstruction in autobiographies as time goes by. Common link is that however fragmented and inaccessible some details or episodes become, we have a core of our "life history" that accurately reflects who we are, and serves to reconstruct memories in a way that is most often "true to ourselves."

The Receding Past. Notes power function of loss over time, suggests interference as important mechnism. Reviews Loftuses' critique of Penfield's claims about permanence, and concludes that although cuing sometimes leads to activation, there may be something like decay at a biological level, and as the engram fades, cues and reconstruction become more important; suggests fading may be adaptive (cf. "S").

Hypermnesia and Consolidation. Briefly touches on hypermnesia in episodic lab tests, suggest its due in part to additional rehearsal/retrieval. STM-LTM consolidation linked to Hebbian changes; cites Aplysia work. Contrasts to a longer-term process of consolidating LTM over years, to explain Ribot's Law of worse amnesia for recent years; notes ECT and Korsakoff analogs. Suggests it reflects increasing independence from medial temporal "indexing" a la Damasio. Notes possibility of sleep & REM as critical in this process (88).

Remembering the Experiences of a Lifetime. Using Isabel Allende's relating her life to her comatose daughter, focusses on Conway & Rubin's hierarchy of autobiog: lifetime periods as the most abstract and organizational; general events as schematic, basic-level composite episodes that are the most distinctive and first remembered upon cuing; and event-specific knowledge. Case of PS, thalamic lesion leads to conviction that it's WW2 and he's on leave. Interesting argument that it's "pathologically on", and other lifetime periods absent' so amnesia comes with anasagnosia - he doesnt' just remember it, he lives it. Finishes with a discussion of whether its all a fabrication, concludes that at least at the generic level, and with rehearsal of specific events, autiobgraphy can withstand the tests of time, and we can remember things accurately if reconstructively.

COMMENTS: Nice balance between the limits to memory over time and persistance. As in previous chapters, mixes the neuropsych pathologies with normal memory and forgetting very nicely. Some is fairly speculative - on biological decay (though see work by Kandel suggesting such a process), on the shift away from hippocampal areas with practice (this seems testable), and the neural reality of the different descriptive levels of autiobio memory (seems close to Rosch's ideas on hierarchies of concepts).

4. REFLECTIONS IN A CURVED MIRROR: Memory Distortion

Using the foundations of varied encoding and constructive cuing, relates many of the lab and everyday examples of schematic distortion and confabulation, false memories, and source amnesia. Chapter begins with cases of false identification of Nazi criminals (Frank Walus & John Demjanjuk) and the contributions of Freud and Bartlett to the notion of how memory distortion may be not just possible but the norm in certain conditions.

The perils of Prior Knowledge: Encoding and distortion. Errors in identification can come from too limited encoding (e.g., verbal descriptions of salient features could be matched by many people - examples of Carbone's alters), or "too much" schematic knowledge (e.g., scripts of baseball). Notes the false memory effect of Roediger & McDermott, sugg its due to generic recall (sweet words), links it to a PET study showing left medial active for both old items and lures, but lateral temporal and frontal distinguishing true and false; ERP study gives similar results when tests are blocked. Some instances may be more retireval than encoding, though. Also, the PET work failed to replicate on fMRI.

Cue that Confuse: Retrieval and Distortion. Notes Dawes' "retrospection bias" - like hindsight bias, where we misremember things as being more consistent with current beliefs or evidence (e.g., political attitudes & toothbrushing), and first notes that the therapy context may heighten the cuing effects. Good section on hypnosis and constructed memories, stressing false confidence. Shopping mall study described, stressing the importance of repeated rehearsals and imaging in producing the effects. Adds John Dean and Anita Hill as recent e.g.'s.

The Woman who Mistook a Psychologist for a Rapist: The Vagaries of Source memory. The theme is the loss of contextual connection for episodes, leading to source confusion and errors. The psychologist is Donald Thompson, of Tulving & Thompson, who was seen on TV by a woman subsequently raped. Notes Loftus' stop/yield study and other misinformation effects, since these at least sometimes may be source problems. Also Jacoby's famous overnight study, & M. Johnson's reality monitoring, stressing importance again of imagery and elaboration. Links to social psych effect of forgetting source of info, and believing it more (Gilbert, 117).

Memory Distortion and the Brain: Source Amnesia and Confabulation. Case study of Gene, who remembers the occasional new fact, but confabulates how he learned it. Other cases of frontal damage and confabulation, some bizarre, described. DS sees it as a failure of the strategic retrieval (frontal function) in face of OK auto-assoc (cuing fragments of episodes, "out of context").

Remembering Phantoms: False recognition and the right frontal lobes. Describes a DS case study of Frank, massive RF lesion, with huge number of false "remember" responses in list tests. Doesn't show it to different-category; suggestion is that anything assoiatively/genericlaly similar to material from past risks false recollection. Odd thing is that it's recollection, not just knowing. Sees R hem as more capable of source discrimination.

The Confabulated Mousetrap: Source Amnesia and the Preschool. Good mixture of case accounts and lab studies by Ceci and others, showing risks of suggestive confabulation in children, but adds that in the absence of misinformation or biased cuing, children's memory can be quite accurate. Lacking kid-adult comparisons.

Reminiscences of a Sheriff's Deputy: finishes with the case of Paul Ingram, accused of sexual abuse by his two children, who subsequently came to believe and embellish the stories, analyzing how the conditions were all that would lead to confabulation.

COMMENTS: Only a few cases of impairment, and most of these are "everyday" distortions in the wrong circumstances that lead to tragic results. The stress is certainly on distortions and errors, but balances it occasionally. Calling misinformation and reconstructive errors all as source amnesia is a bit braoder use of the term than I'd like; and note that it's not just failure to identify source but falsely remember it that leads to the worst errors.

5. VANISHING TRACES: Amnesia and the Brain

The core chapter on brain damage and memory impairment. Starts with a golf round with Fred, a sever antero from Alzheimer's. Emphasis is on episodic explicit amnesia, the classic amnestic syndrome of mostly anterograde; retrograde autobio amnesia, and its dissociation from semantic amnesias and anomias.

Making Amnesics: The Machinery of Memory. HM's extensive medial temporalectomy desribed, along with severe antero and notable retro; several more recent and restricted cases with signif but not profound amnesia. Davide Jane, an artist, with enceph destruction of left hem, verbal lang and memory imparied, but visual/painting skills OK. Brief account of mishkin's monkey leasions, and debate over hippocampus versus surround; suggests parahipp cortex most important (143-145). Korsakoff syndrome (note sudden onset stage) and diencephalon amnesia linked to Papez entorhinal circuit. The retro part obey's Ribot's Law, again showing role of medial temporal and related structures in "recent" memory and new memory.

When the Past Disappears: Retrograde Amnesia and the Structure of Memory. Motocycle accident left Gene densely retro, with no autobio detail, only "life periods" which DS suggests is due to semantic, not reollective, memory (152). Section ends with semantic "dementias" and the living/nonliving distinction, linked to sensory/visual versus action. Includes Martin 96's work.

Experiencing Amnesia. Theme of anosagnosia, how it correlates (imperfectly) with frontal damage and confabulation, and questions when it might be a blessing.

6. THE HIDDEN WORLD OF IMPLICIT MEMORY

Schacter shines in his own element. Traces the emergence of the view that implicit memory is a distinct from of remembering, and not limited to perceptual or motor priming/learning.Covers seminal studies for both amnestics and normals, and theme is unconscious plagiarism and its roots.

Why do Amnestic Patients Learn? On sabbatical with Tulving at Oxford, DS learns of Warrington & Weiskranz' fragment-completion results with amnestics; back in toronto, Mickey, an amnestic. Learns new triva but forgets source. Apply to normals and show dissociations from explicit memory. Argues its' not just semantic activation, given absence of LOP effects on implicit tasks. Inroduces "implicit" as new form of memory. Notes other phenom that look implicit, like learning during anesthesia (172), conditioning and context effects in infants (173-75).

Putting Priming to Work: The story of Barbara. Encephalitis leaves Barbara densely anterograde; DS' clinic develops a "vanishing cue" method analogous to fragment-priming, and shows she can learn enough data entry skills to get a full-time new job. Highly dependent on wording, apparently. Some discussion in notes of importantce of "error-free" (and so interference-free) training.

Objects of the Mind. Reviews work with Cooper on object priming, sugg failure to get priming for impossible objects reflects priming in "perceptual represention system" (PRS) in inferior temporal lobe (site of "global" form awareness in monkey work) though recent stuff in notes sugg complexity confound and possible decision bias. Still, point of nonverbal pictorial priming is clear.

Beyond Perceptual Priming. Notes work showing procedure learning and implicit priming (a la Lewicki, by Nissen), and a conceptual priming effect using ambiguous sentences that can be understood with thematic cue word. (Why then doesn't cross-modal priming work? Is there syntactic analog to implicit specificity?)

COMMENTS: Nice overview of implicit memory, again a mix of normal and patients that we can expect throughout.

7. EMOTIONAL MEMORIES: When the Past Persists.

Theme here is that memories established under conditions of arousal may indeed be more accurate and more resistant to loss, than everyday memories, even though they are subject to the same risks of encoding and retireval distortion and reconstruction.. We see this both for flashbulb memories, and for those dealing with personal trauma, as the case of the chicago artist with memories of an apartment fire that he begins the chapter with.

Flashbulb Memories: Where Were You Then? Starts with classic Brown & Kulik survey and suggestion about "consequentiality" (e.g., Americans vs Brits reaction to Thatcher's resignation). Notes Chirstianson & Neisser's demonstration of false memories and distortions (198-99) as in part source amnesia of mixing elements together, and tendency to higher confidence for flashbulb than everyday memories from diary studies. Suggests additional rehearsal and distinctive encoding can't explain it all, and arousal has a role.

Personal Trauma: The Persistence of Memory. From skywalk collapse to Holocaust survivors, states that "the most common symptom is unbidden recollection of the trauma, with emotional disturbance and spotty memory problems." (203).

Traumatic memories: How accurate are they? Looking at the Chowchilla kidnapping, and combat stress, sees "flashbacks" as mixtues of reality, fears and hopes (e.g., kids at a shooting incident remembering themselves as "safer" than in fact; soldier's "remembing" their worst fears; inflated "recognition" of De Rijke by Camp survivors who had seen a nationally televised show with his picture).

Experimenting with Emotion: What do we remembe from Emotional Experiences? High arousal remembered better in lab studies, whether positive or negative. Arousal can narow attention; notes weapon focus. Describes depression and mood-congruent retrieval (211-12).

The Brain's Almond: Amygdala, Emotion and Memory. Starts with Kluver-Bucy syndrome, and links to amygdala. Damasio study dissociating explicit memory loss with intact emotional conditioning with hipp/temp damage, versus the opposite pattern with amygdala damage (214). Reviews evidence that amygdala mediates release of stress-related hormones; e.g., the drug propanolol, which blocks these hormones, eliminates the arousal advantage in explicit memory (Cahill & McGaugh).

COMMENTS: Chapter as a whole is on the thin side, but does a good job with basic info on flashbulb and traumatic memory. Could add more on amygdala role & complexity, on congruency effects, and PTSD. (See Kunious' ERP study). Good balance on increased accuracy but still "normal" memory processes.

8. ISLANDS IN THE FOG: Psychogenic Amnesia.

Includes a variety of cases where trauma leads not to better memory, but to either specific-event amnesia at one end, or to global amnesia and "fugues", or multiple personalities, on the other. Begins with his personal case of Lumberjack, a global fugue resulting from the death of a close grandfather, during which only an "island" of life period of postal courier survived; it suddenly lifts when a TV funeral in Shogun triggers that of the grandfather, where his fugue began.

When the Mind Forgets itself: Beyond Lumberjack. Kritschevsky notes diversity of memory problems and recovery patterns for pyschogenics. Suggests that in many cases, though, current stress linked to earlier brain trauma may increase succeptibility (225).

Holes in the Past: Limited Amnesia. Notes high incidence of claims of amnesia by perpetrators of violent crime; in Sirhan's case, sides with recent analysis by Moldea that state-dependency isn't the case, and Sirhan is a malingerer (227). Discusses other potential causes of amnesia in these cases, including intoxication, head injury, etc. versus emotion per se. Believes other cases of "remote" memories of trauma that may be triggered by new stress; theme is less "repression" than state-dependence.

Leaks from the Past: Implicit memory for Traumatic Events. Includes classic case of women in fugue state who "automatically" dials the phone number of her mother, and other instances of emotionality or "bleed through" of imagery (of a brick path, for example) in the face of explicit amnesia for events, a theme from Freud. Note this section relies on implicit memory chapter.

How the Past is Lost: Dissociation, Repression and Inhibition. Contrasts ideas of repression for specific events & episodes, and the more powerful "horizontal" splits and dissociations for fugues and DID's, but says they're"difficult to test and neither provide convincing explanations." (234). Sees inhibitory mechanisms as important, reviews recent "retrieval-induced forgetting" paradigm of Anderson & Bjork (235).

Multiple Personalities: Dissociation or Invention? Notes suspicious increase in cases, and number and variety of "alters", following publicity like "Sybil." Still, looks at Nissen's patient, with four alters, some of whom are amnestic for the others. Across alters, which by def showed autobiog amnesia for the others, DS & Nissen show normal fragement-completion and other percpetual implicit tasks, but little conceptual priming (on the ambiguous-sentence task). Discusses the contoversy about whether many, or all DID cases resulted from early sexual abuse, anticipating the therapy/hypnosis issues of the next chapter (240-43).

Stressful Expeierence and the Brain: Clues to Psychogenic Amnesias? A speculative section on neural mechanisms; describes possible hippocampus damage mediated by release of too much glucocorticoids, but doesn't see this as an explanation for dissociative effects.

COMMENTS: Great chapter that spans the range of psychogenic amnesias; I'd like some more on attempts to produce repression in lab, and case studies of genuine recovery. Could bring in more on directed-forgetting and inhibition paradigms too.

9. THE MEMORY WARS: Seeking Truth in the Line of Fire

A balanced and detailed synopsis of the controversy over repressed / recovered memories. Less strident than Loftus, touches on more topics than Searleman; for example, discusses how to assess accuracy of recovered memories, and the issue of whether repeated abuse is more or less likely to be remembered. The bottom line is a skeptical one, though. Begins with two cases, one of retraction of memories of satanic abuse, the other, a confirmed case of recovered memory for an incident of adolescent sexual abuse.

Forgetting abuse: How often does it happen and why? Starts with cases of "intentional suppression/lack of rehearsal", a kind of conscious withdrawal from the episode, but no evidence this strategy can produce the kind of "serious amnesia" of repression, at least in narrow, later sense that Freud used the term (unconscious defense). Since traumatic events are usually remembered very well, or too well (see previous chapter), burden is on demonstration of repression. Lenore Terr suggests repeated trauma leads to "practice at repression", but evidence suggests for both everyday and traumatic experiences, repetition increases recall - though it may schematize things that could lead to "amnesia" for specific event details (257-59). Case studies of apparent forgetting of documented abuse may be normal forgetting, childhood amnesia, etc. (261). In genuine cases of forgetting, esp those that seem "immediate", DS suggests dissociative mechanisms, rather than specific-event repression.

Recovered Memories: How Accurate Are They? In cases of documented recovery, we rarely can assess accuracy. Since flashbacks and flashbulbs don't guarantee accuracy, it's unlikely recovered memories are any more accurate, although some have argued their frozen nature protects them from change or distortion.

Illusory Memories of Sexual Abuse: What is the Evidence? On several grounds, concludes that the evidence is strong for illusory memories being a reality. These include improbability of claims themselves (satanic rituals, with no evidence after a thousand claims), similarity of induction and confidence to impossible claims (past lives, alien adbuction), evidence of how easy it is to implant memories with the sort of manipulations that happen in therapy (hypnosis, group therapy and reinforcment, guided visualization).

Distinguishing Accurate and illusory recollections: The role of implicit memory. Suggests that although implicit clues of memory in the absence of recollection may be common in genuine cases, it's very difficult to use these as evidence for repression, since these may be turned around and serve as seeds for construction of memories as well. Reviews cases where memories of abuse are associated with obsessive-compulsive disorder.

Beyond Controversy. Besides stressing the need for balance and case-by-case evaluation, notes that even in cases of illusory memories, they "capture something about the past that should not be dismissed."

COMMENTS: One of the best overviews, with great detail and useful case studies, more compact too than Loftus or other recent books. See current Directions recent issue (dec97) for additional papers by DS, Loftus, and others on memory illusions.

10. STORIES OF ELDERS

A nice way to wrap things up, acknowledging some of the memory changes with aging (more modest than myths would have it), but concludes stressing the intergenerational, social role of memories as stories from our ancestors. Begins with a fictional case of aging and forgetting, LittleJohn McCain (Howard Owen novel), and the role of memory in the art of the elderly.

Aging memory: How Fragile is it? Argues that the diversity of outcomes in young-old comparisons shows it's not just a general decline. Focus is on how frontal-lobes impairments, perhaps due to drop in basal forebrain cholinergic supply, explains many of the specific problems older people have in memory tasks, including strategic search, source amnesia, excessive working memory demands, etc. Notes evidence that semantic memory, and procedural memory, relatively intact, though some changes may occur. (292). Decline in incidence of flashbulb memories in elderly is discussed.

Reviewing a Life: Intensifying Memory's Powers. "Reminiscence" among the elderly may be an adaptive part of aging, esp if focus is on "plans and goals, reconiling past and present" (297). Notes the phenomenon of the "adolescent bump" in number of clarity of memories from teen and young adult years; seen as part of establishing the "life story" that is so important in remeniscence.

Aging Storytellers: Bridging Generational Time. Talks of how in nonwestern cultures, the elderly as keepers of the culture led to honoring their memory roles as tellers of the culture's story. With easy "external memory" this role has been downp[layted; but photos and other "externalized memories" cna still play a role as a way to "cry out to the future to say that we did exist and that we were important." (306).

COMMENTS: A sensitive account of memory in the elderly. The review of impairments is fair, though emphasis on frontal deterioration a bit strong; also might note recent ideas of compensation, and successful maintenance of performance in the elderly.