Exploring the recognition memory deficit in Parkinson's disease: estimates of recollection versus familiarity.
(1/5)
Current theories postulate that recognition memory can be supported by two independent processes: recollection (i.e. vivid memory for an item and the contextual details surrounding it) versus familiarity (i.e. the mere sense that an item is old). There is conflicting evidence on whether recognition memory is impaired in Parkinson's disease, perhaps because few studies have separated recollection from familiarity. We aimed to explore whether recollection or familiarity is more likely to be affected by Parkinson's disease, using three methods: (i) the word-frequency mirror effect to make inferences about recollection and familiarity based on recognition of high- versus low-frequency words, (ii) subjective estimates of recollection (remembering) versus familiarity (knowing), and (iii) a process-dissociation procedure where participants are required to endorse only some of the previously studied items on a recognition memory test, but not others. We tested Parkinson's disease patients (n = 19 and n = 16, age range = 58-77 years and age range = 50-75 in Experiments 1 and 2, respectively) and age- and education-matched controls (n = 23 and n = 16 in Experiments 1 and 2, respectively). Overall, the Parkinson's disease group showed a reduction in recognition memory, but this appeared to be primarily due to impairment of familiarity, with a lesser decline in recollection. We discuss how this pattern may be related to dysfunction of striatal, prefrontal and/or medial temporal regions in Parkinson's disease. (+info)
The FN400 indexes familiarity-based recognition of faces.
(2/5)
Separate event-related brain potential (ERP) components have been hypothesized to index familiarity and recollection processes that support recognition memory. A 300- to 500-ms mid-frontal FN400 old/new difference has been related to familiarity, whereas a 500- to 800-ms parietal old/new difference has been related to recollection. Other recent work has cast doubt on the FN400 familiarity hypothesis, especially its application to familiarity-based recognition of conceptually impoverished stimuli such as novel faces. Here we show that FN400 old/new differences can be observed with novel faces, and as predicted by the familiarity hypothesis, these differences are observed regardless of whether or not recognition is accompanied by the recollection of specific details from the study episode. Furthermore, FN400 differentiation between hits and misses is more consistent with an explicit familiarity process than an implicit memory process. (+info)
Impaired familiarity with preserved recollection after anterior temporal-lobe resection that spares the hippocampus.
(3/5)
It is well established that the medial-temporal lobe (MTL) is critical for recognition memory. The MTL is known to be composed of distinct structures that are organized in a hierarchical manner. At present, it remains controversial whether lower structures in this hierarchy, such as perirhinal cortex, support memory functions that are distinct from those of higher structures, in particular the hippocampus. Perirhinal cortex has been proposed to play a specific role in the assessment of familiarity during recognition, which can be distinguished from the selective contributions of the hippocampus to the recollection of episodic detail. Some researchers have argued, however, that the distinction between familiarity and recollection cannot capture functional specialization within the MTL and have proposed single-process accounts. Evidence supporting the dual-process view comes from demonstrations that selective hippocampal damage can produce isolated recollection impairments. It is unclear, however, whether temporal-lobe lesions that spare the hippocampus can produce selective familiarity impairments. Without this demonstration, single-process accounts cannot be ruled out. We examined recognition memory in NB, an individual who underwent surgical resection of left anterior temporal-lobe structures for treatment of intractable epilepsy. Her resection included a large portion of perirhinal cortex but spared the hippocampus. The results of four experiments based on three different experimental procedures (remember-know paradigm, receiver operating characteristics, and response-deadline procedure) indicate that NB exhibits impaired familiarity with preserved recollection. The present findings thus provide a crucial missing piece of support for functional specialization in the MTL. (+info)
Posttraumatic stress disorder caused by the misattribution of seizure-related experiential responses.
(4/5)