Memory consists of various individual processes which form a dynamic system co-ordinated by central (executive) functions. The episodic buffer as direct interface between episodic long-term memory (LTM) and working memory (WM) is fairly well studied but such direct interaction is less clear in semantic LTM. Here, we designed a verbal delayed-match-to-sample task specifically to differentiate be...

Computational models of semantics infer semantic structure from the analysis of large linguistic corpora. Two approaches are described here. In each case the data consist of a document-by-word matrix, counting the number of times a word was used in a document. Latent Semantic Analysis uses dimension reduction to construct a high-dimensional semantic space from such a matrix. Information in sema...

Meaning is a fundamental component of nearly all aspects of human cognition, but formal models of semantic memory have classically lagged behind many other areas of cognition. However, computational models of semantic memory have seen a surge of progress in the last two decades, advancing our knowledge of how meaning is constructed from experience, how knowledge is represented and used, and wha...

This study examined the recollection of autobiographical material in memory among Iranian military veterans with and without posttraumatic stress disorder (PTSD), and healthy non-trauma-exposed control subjects. Participants completed the Autobiographical Memory Test, Autobiographical Memory Interview (counterbalanced), Impact of Event Scale-Revised, Beck Depression Inventory-II, Wechsler Memor...

We present an extension of the search of associative memory (SAM) model that simulates the effects of both prior semantic knowledge and prior episodic experience on episodic free recall. The model incorporates a memory store for preexisting semantic associations, a contextual drift mechanism, a memory search mechanism that uses both episodic and semantic associations, and a large lexicon includ...

This study investigated the neural bases of event-related semantic-memory deficits among people with aphasia due to left-hemisphere (LH) stroke. A novel task using naturalistic photographic stimuli and patient-friendly procedures was used to test event-related semantic knowledge. In the task, participants decided whether depicted events were normal (represented in semantic memory) or were abnor...

The distinction between memory for events and memory for facts rests on a range of findings indicating that different memory systems respectively subserve episodic and semantic memory functions. Whereas general knowledge clearly affects memory for events, the respective roles of encoding and retrieval processes in this interaction remain unclear. Using intracranial electroencephalography and mu...

This study examined the case of a brain-damaged patient, I.R., who exhibits the pattern of performance typical of persons with a selective short-term memory deficit. Part 1 reveals a dissociation in performance between impaired shortterm memory and preserved long-term memory. Part 2 examines an alternative explanation of I.R. s performance under a processing view of memory that rejects the noti...

We examined autobiographical memory performance in two patients with semantic dementia using a novel measure, the Autobiographical Interview [Levine, Svoboda, Hay, Winocur, & Moscovitch (2002). Aging and autobiographical memory: Dissociating episodic from semantic retrieval. Psychology and Aging, 17, 677-689], that is capable of dissociating episodic and personal semantic recall under varying l...

Semantic memory is an integral part of intelligent systems dealing with natural language processing (NLP). Building these memories is a challenging task. Different approaches have been proposed and tested, using a variety of corpuses. The corpora used to build the semantic memories vary from well structured to highly unstructured. The more structured a corpus, the easier it is to build a semant...