Various apparently incompatible theories of hippocampal function have been proposed but integration is now needed. It is argued that the involvement of the hippocampus is most clearly seen when the animal needs to extrapolate beyond current sensory information. Such control can involve both the initiation of behaviour in the absence of appropriate sensory input and the inhibition of behaviour that might otherwise be triggered by current sensory input.

Clinical use of the term “confabulation” began as a reference to false memories in dementia patients. The term has remained in circulation since, which belies shifts in its definition and scope over time. “Confabulation” now describes a range of disorders, deficits, and anomalous behaviors. The increasingly wide and varied use of this term has prompted many to ask: what is confabulation? In recent years, many have offered answers to this question. As a general rule, recent accounts are accounts of broad (...) confabulation: attempts to unify the seemingly disparate features of all or most confabulatory phenomena under a shared set of characteristics or mechanisms. In this paper, I approach the question differently. I focus on a particular form of confabulation—mnemonic confabulation—so as to understand its distinctive features and the ways in which it does fit into accounts of broad confabulation. Understanding mnemonic confabulation is a project in the philosophy of memory; it plays an important role in guiding theories of remembering, as a form of error that must be distinguished from genuine remembering. Mnemonic confabulation, as I define it in Sect. 2, occurs when there is no relation between a person’s seeming to remember a particular event or experience and any event or experience from their past—either because there is no such event in their past or because any similarity to such an event is entirely coincidental. This account draws on my own theory of remembering, but shares many important points of consensus with other accounts of mnemonic confabulation, which I highlight in Sect. 3. In Sect. 4, I turn to accounts of broad confabulation—identifying three features such accounts have in common—and, for each, I argue that mnemonic confabulation lacks the requisite feature. As an error, mnemonic confabulation has more in common with perceptual hallucination than with the confabulatory phenomena included in standard accounts of broad confabulation. Recognizing that, despite the shared use of the term “confabulation” mnemonic confabulation and broad forms of confabulation are unrelated, is important for continued progress in debates about each. (shrink)

Confabulation is a symptom central to many psychiatric diagnoses and can be severely debilitating to those who exhibit the symptom. Theorists, scientists, and clinicians have an understandable interest in the nature of confabulation—pursuing ways to define, identify, treat, and perhaps even prevent this memory disorder. Appeals to confabulation as a clinical symptom rely on an account of memory’s function from which cases like the above can be contrasted. Accounting for confabulation is thus an important desideratum for any candidate theory of (...) memory. Many contemporary memory theorists now endorse Constructivism, where memory is understood as a capacity for constructing plausible representations of past events. Constructivism’s aim is to account for and normalize the prevalence of memory errors in everyday life. Errors are plausible constructions that, on a particular occasion have led to error. They are not, however, evidence of malfunction in the memory system. While Constructivism offers an uplifting repackaging of the memory errors to which we are all susceptible, it has troubling implications for appeals to confabulation in psychiatric diagnosis. By accommodating memory errors within our understanding of memory’s function, Constructivism runs the risk of being unable to explain how confabulation errors are evidence of malfunction. After reviewing the literature on confabulation and Constructivism, respectively, I identify the tension between them and explore how different versions of Constructivism may respond. The paper concludes with a proposal for distinguishing between kinds of false memory—specifically, between misremembering and confabulation—that may provide a route to their reconciliation. (shrink)

Eichenbaum et al. (1994a) hypothesized that perceptually distinct items and the relations among them are processed sequentially by the parahippocampal region and the hippocampal formation, respectively. Predictions based solely on their model's sequential-processing feature might prove easier to disconfirm than those based on its representational features. Two such predictions are discussed: (1) double dissociations should be impossible following hippocampal vs. parahippocampal lesions, and (2) hippocampal lesions should not exacerbate impairments that follow complete parahippocampal lesions.

Why is consciousness associated with recovery of memories that are initially dependent on the hippocampal system? A hypothesis is proposed that the medial temporal lobe/hippocampal complex (MTL/H) receives as its input only information that is consciously apprehended. By a process termed “cohesion,” the MTL/H binds into a memory trace those neural elements that mediated the conscious experience so that effectively, “consciousness” is an integral part of the memory trace. It is the phenomenological records of events (Conway 1992), integrated consciousness-content packets, (...) that are recovered when memory traces are retrieved. (shrink)

Continuing commentary raised several issues concerning our proposal that the hippocampus, parahippocampal region, and cortical association areas mediate different aspects of memory function. Recent relevant findings strengthen our argument that neocortical areas and the parahippocampal region maintain persistent encodings of specific single items and that the hippocampus mediates representations of the relations among these items. The reciprocally and closely interconnected structures that compose the hippocampal memory system work interactively to support flexible memory expression that is relevant to the natural behavior (...) of animals and to conscious recollection in humans. (shrink)

Eichenbaum et al.'s (1994a) theory suffers from a lack of ecological validation. It is not at all clear why the hypothesized faculties would have evolved and what their adaptive value would be. I argue that hippocampal function can only be understood if the animal is seen in its natural context.

We raise three issues concerning the Eichenbaum, Otto & Cohen (1994) model. (1) We argue against the strict division of labor that Eichenbaum et al. attribute to neocortical and limbic regions. (2) We raise the possibility that the anterior and posterior portions of the hippocampus may be important for different types of information processing. (3) We argue that, rather than reflecting relational processing, different neural responses to “match” and “nonmatch” trials may relate to different required spatial responses.

This paper attempts to answer the question of what defines mnemonic confabulation vis-à-vis genuine memory. The two extant accounts of mnemonic confabulation as “false memory” and as ill-grounded memory are shown to be problematic, for they cannot account for the possibility of veridical confabulation, ill-grounded memory, and wellgrounded confabulation. This paper argues that the defining characteristic of mnemonic confabulation is that it lacks the appropriate causal history. In the confabulation case, there is no proper counterfactual dependence of the state of (...) seeming to remember on the corresponding past representation. (shrink)