Psychometric properties of the Folstein Mini-Mental State Examination

Criterion-referenced (Livingston) and norm-referenced (Gilmer-Feldt) techniques were used to measure the internal consistency reliability of Folstein's Mini-Mental State Examination (MMSE) on a large sample (N = 418) of elderly medical patients. Two administration and scoring variants of the MMSE Attention and Calculation section (Serial 7s only and WORLD only) were investigated. Livingston reliability coefficients (rs) were calculated for a wide range of cutoff scores. As necessary for the calculation of the Gilmer-Feldt r, a factor analysis showed that the MMSE measures three cognitive domains. Livingston's r for the most widely used MMSE cutoff score of 24 was .803 for Serial 7s and .795 for WORLD. The Gilmer-Feldt internal consistency reliability coefficient was .764 for Serial 7s and .747 for WORLD. Item analysis showed that nearly all of the MMSE items were good discriminators, but 12 were too easy. True score confidence intervals should be applied when interpreting MMSE test scores.     

The<Emphasis Type="Italic">remember</Emphasis> response: Subject to bias,graded, and not a process-pure indicator of recollection

Recognition memory judgments have long been assumed to depend on the contributions of two underlying processes: recollection and familiarity. We measured recollection with receiver-operating characteristic (ROC) data and remember-know judgments. Under standard remember-know instructions, the two estimates of recollection diverged. When subjects were told they might need to justify theirremember responses to the experimenter, the two estimates were more likely to agree. The data support the conclusion thatremember responses are generally based on a continuous underlying process but that specific task instructions can produce data that appear consistent with a high-threshold recollective process. Models based on signal detection theory provide a better account of these data than does the dual-process model (Yonelinas, 1994) or process-pure interpretations.     

Short-term recall of order information: Influence of encoding and generation processes on distinctiveness,isolation, and background effects

We examined the influence of encoding and generation processes on distinctiveness, isolation, and background effects in short-term recall of order information. Adults recalled the order of letters in one of two segments following a distractor task, knowing in advance the identity of the letters. A distinctive letter was one that was either in red or absent and replaced with a red dash, thereby requiring generation. On trials with a distinctive letter, the letter was primed in advance. A negative generation effect was found; in addition, there was a positive distinctiveness effect but a negative background effect on trials in which generation was required. These effects can be explained in terms of the extra processing given to distinctive items when they need to be generated.     

Basic processes in reading: Is visual word recognition obligatory?

Visual word recognition is commonly argued to be automatic in the sense that it is obligatory and ballistic. The present experiments combined Stroop and visual search paradigms to provide a novel test of this claim. An array of three, five, or seven words including one colored target (a word in Experiments 1 and 2, a bar in Experiment 3) was presented to participants. An irrelevant color word also appeared in the display and was either integrated with or separated from the colored target. The participants classified the color of the single colored item in Experiments 1 and 3 and determined whether a target color was present or absent in Experiment 2. A Stroop effect was observed in Experiment 1 when the color word and the color target were integral, but not when the color word and the color target were separated. No Stroop effect was observed in Experiment 2. Visual word recognition is contingent on both the distribution of spatial attention and task demands.     

Revisiting the role of recollection in item versus forced-choice recognition memory

Many memory theorists have assumed that forced-choice recognition tests can rely more on familiarity, whereas item (yes-no) tests must rely more on recollection. In actuality, several studies have found no differences in the contributions of recollection and familiarity underlying the two different test formats. Using word frequency to manipulate stimulus characteristics, the present study demonstrated that the contributions of recollection to item versus forced-choice tests is variable. Low word frequency resulted in significantly more recollection in an item test than did a forced-choice procedure, but high word frequency produced the opposite result. These results clearly constrain any uniform claim about the degree to which recollection supports responding in item versus forced-choice tests.     

Speeded retrieval abolishes the false-memory suppression effect: Evidence for the distinctiveness heuristic

We examined two different accounts of why studying distinctive information reduces false memories within the DRM paradigm. The impoverished relational encoding account predicts that less memorial information, such as overall familiarity, is elicited by the critical lure after distinctive encoding than after nondistinctive encoding. By contrast, the distinctiveness heuristic predicts that participants use a deliberate retrieval strategy to withhold responding to the critical lures. This retrieval strategy refers to a decision rule whereby the absence of memory for expected distinctive information is taken as evidence for an event’s nonoccurrence. We show that the typical false-recognition suppression effect only occurs when the recognition test is self paced. This suppression effect is abolished when participants make recognition decisions under time pressure, such as within 1 second of seeing the test item. These results are consistent with the distinctiveness heuristic that a time-consuming retrieval strategy is used to reduce false-recognition responses.     

Stimulus-response compatible orienting and the effect of an action not taken: Perception delayed is automaticity denied

Orienting to a signal source is widely viewed asautomatic in the sense that it is triggered by the stimulus. However, this behavior is typically assessed in a context in which the subject knows beforehand what he or she has to do. In the present experiments, the role of task set was investigated by having the response vary randomly from trial to trial. On some trials, a cue signaled the subject to respond, and on the remaining trials, another cue signaled the subject to withhold a response. Stimulus contrast and temporal overlap between task cue and target were manipulated. The effect of a reduction in stimulus contrast was sometimes absorbed into the time taken to decode the cue, but critically, other times not. These results highlight the theoretical importance of considering task set as an essential element in processing, and they undermine the theoretical claim that putatively automatic processes are not subject to interference from other mental activities.     

Looking at the rope when looking for the snake: Conceptually mediated eye movements during spoken-word recognition

Participants’ eye movements to four objects displayed on a computer screen were monitored as the participants clicked on the object named in a spoken instruction. The display contained pictures of the referent (e.g., a snake), a competitor that shared features with the visual representation associated with the referent’s concept (e.g., a rope), and two distractor objects (e.g., a couch and an umbrella). As the first sounds of the referent’s name were heard, the participants were more likely to fixate the visual competitor than to fixate either of the distractor objects. Moreover, this effect was not modulated by the visual similarity between the referent and competitor pictures, independently estimated in a visual similarity rating task. Because the name of the visual competitor did not overlap with the phonetic input, eye movements reflected word-object matching at the level of lexically activated perceptual features and not merely at the level of preactivated sound forms.     

An introduction to Bayesian hierarchical models with an application in the theory of signal detection

Although many nonlinear models of cognition have been proposed in the past 50 years, there has been little consideration of corresponding statistical techniques for their analysis. In analyses with nonlinear models, unmodeled variability from the selection of items or participants may lead to asymptotically biased estimation. This asymptotic bias, in turn, renders inference problematic. We show, for example, that a signal detection analysis of recognition memory data leads to asymptotic underestimation of sensitivity. To eliminate asymptotic bias, we advocate hierarchical models in which participant variability, item variability, and measurement error are modeled simultaneously. By accounting for multiple sources of variability, hierarchical models yield consistent and accurate estimates of participant and item effects in recognition memory. This article is written in tutorial format; we provide an introduction to Bayesian statistics, hierarchical modeling, and Markov chain Monte Carlo computational techniques.