Differential perseverations in verbal retrieval related to anterior and posterior left hemisphere lesions

Sixty-two patients with focal cerebral lesions and 11 control patients were examined using alternating tasks of learning, generation, and recall of words beginning with "K." The results supported the hypothesis that "recurrent" and "stuck-in-set" varieties of perserveration are related to posterior and anterior left hemisphere lesions, respectively. Patients with left posterior lesions usually failed to suppress the expression of previously generated words in the subsequent generation task, whereas patients with left anterior lesions stated a greater number of new (incorrect) words in the recall of previously learned words, presumed to indicate stuck-in-set perseveration of the previous generation performance.     

Dissociated naming and locating of body parts after left anterior temporal lobe resection: An experimental case study

After resection of the left anterior temporal lobe, a 17-year-old girl showed a dissociation of the verbal and nonverbal elements of lateral body orientation. She could identify body parts and body side on herself or on a confronting person, but was impaired in producing and understanding body part names. The verbal and topographic components of body orientation are neurally separable since they can be differently affected by cerebral damage.     

Regularity of unit length boosts statistical learning in verbal and nonverbal artificial languages

Humans have remarkable statistical learning abilities for verbal speech-like materials and for nonverbal music-like materials. Statistical learning has been shown with artificial languages (AL) that consist of the concatenation of nonsense word-like units into a continuous stream. These ALs contain no cues to unit boundaries other than the transitional probabilities between events, which are high within a unit and low between units. Most AL studies have used units of regular lengths. In the present study, the ALs were based on the same statistical structures but differed in unit length regularity (i.e., whether they were made out of units of regular vs. irregular lengths) and in materials (i.e., syllables vs. musical timbres), to allow us to investigate the influence of unit length regularity on domain-general statistical learning. In addition to better performance for verbal than for nonverbal materials, the findings revealed an effect of unit length regularity, with better performance for languages with regular- (vs. irregular-) length units. This unit length regularity effect suggests the influence of dynamic attentional processes (as proposed by the dynamic attending theory; Large & Jones (Psychological Review 106: 119–159, 1999)) on domain-general statistical learning.     

Memory for verbal and nonverbal stimuli in learning disability subgroups: analysis by selective reminding

Memory for verbal and nonverbal stimuli was evaluated using selective reminding procedures in normal achieving children and four groups of disabled learners: (1) reading-spelling disabled (R-S); (2) reading-spelling-arithmetic disabled (R-S-A); (3) spelling-arithmetic disabled (S-A); and (4) arithmetic disabled (A). Each child received two analogous free-list memory tasks, one for verbal material (animal names) and the other for nonverbal material (random dot patterns). These tasks were administered using selective reminding procedures that permit separation of storage and retrieval aspects of memory by reminding children only of those words not recalled on previous trials. Results revealed that relative to controls, the A and S-A children had significantly lower storage and retrieval scores on the nonverbal task, but did not differ on the verbal task; the R-S children differed only on retrieval scores from the verbal task; and the R-S-A children on retrieval scores on the verbal task and storage and retrieval scores on the nonverbal task. Thus, results indicate that the memory performance of disabled learners varies according to (1) the type of learning problem (arithmetic vs reading), (2) the nature of the stimuli (verbal vs nonverbal), and (3) the aspect of memory being assessed (storage vs retrieval). This study provides external validation for the classification of disabled learners according to patterns of academic achievement, demonstrating a useful procedure for dealing with the intrasubject variability characteristic of disabled learners.     

Modality-specific interference with verbal and nonverbal stimulus information

Subjects recalled both letters and the locations of letters in 2 by 3 and 1 by 6 matrices after either no interfering activity or visual, auditory, or kinesthetic interfering activity. Results for each type of matrix indicated the presence of selective auditory (verbal) interference with the recall of letter identity and selective visual and kinesthetic interference with the recall of letter location. Supplementary correlational analyses indicated that the presence of such a dual encoding strategy was most consistent across subjects for the 2 by 3 matrix. Although the results indicated that use of different modes of representation was related to the verbal-nonverbal nature of the information, it was shown that the structure of the stimulus array also affected the nature of the representation.     

Matched false-belief performance during verbal and nonverbal interference

Language has been shown to play a key role in the development of a child's theory of mind, but its role in adult belief reasoning remains unclear. One recent study used verbal and nonverbal interference during a false-belief task to show that accurate belief reasoning in adults necessarily requires language (Newton & de Villiers, 2007). The strength of this inference depends on the cognitive processes that are matched between the verbal and nonverbal inference tasks. Here, we matched the two interference tasks in terms of their effects on spatial working memory. We found equal success on false-belief reasoning during both verbal and nonverbal interference, suggesting that language is not specifically necessary for adult theory of mind.     

The effect of newly trained verbal and nonverbal labels for the cues in probabilistic category learning

Learning in a well-established paradigm of probabilistic category learning, the weather prediction task, has been assumed to be mediated by a variety of strategies reflecting explicit learning processes, such as hypothesis testing, when it is administered to young healthy participants. Higher categorization accuracy has been observed in the task when explicit processes are facilitated. We hypothesized that furnishing verbal labels for the cues would boost the formation, testing, and application of verbal rules, leading to higher categorization accuracy. We manipulated the availability of cue names by training separate groups of participants for three consecutive days to associate hard-to-name artificial auditory cues to pseudowords or to hard-to-name ideograms, or to associate stimulus intensity with colors; a fourth group remained unexposed to the cues. Verbal labels, cue individuation, and exposure to the stimulus set each had an additive effect on categorization performance in a subsequent 200-trial session of the weather prediction task using these auditory cues. This study suggests that cue nameability, when controlled for cue individuation and cue familiarity, has an effect on hypothesis-testing processes underlying category learning.     

Temporal ordering deficits following anterior temporal lobectomy

Subjects were required to report the pitch sequence of two 10-msec tones of different frequency presented monaurally while the stimulus onset asynchrony (SOA) between the two tones was varied. The value of the SOA at which the subjects achieved an 80% correct sequence report was determined by an adaptive procedure without feedback. This measure was compared in the right and left ears, on subjects with a right or left anterior temporal lobectomy and on a normal control group. The results reveal an elevated threshold for performing temporal order judgments in the ear contralateral to the surgical lesion.     

Identifying emergent leaders from verbal and nonverbal communications.

Subject/observers were accurate in identifying emergent leadership hierarchies on four leadership dimensions when provided records of target groups' meetings containing only verbal communications, only nonverbal communications, or both types of behavior. With knowledge of participation rates controlled by covariance, the subject/observers' accuracy scores retained significance in three of the information conditions demonstrating the presence of verbal and nonverbal leadership cues independent of participation rates. The value of verbal and nonverbal communications to identifying leaders varied with the type of leadership hierarchy being identified. The findings are presumed to hold for leader selection as well. The author proposes that the question of why a group member has emerged to fulfill a leadership role in a group be studied from the point of view of group members' selecting leaders or permitting emergence rather than leaders emitting behaviors.     

Dichhaptic hand-order effects with verbal and nonverbal tactile stimulation

The palms of normal right-handed subjects were stimulated dichhaptically, i.e., with competing, bimanually presented tactile stimuli consisting of pairs of letters, pairs of digits, or pairs of line orientations. The subjects were required to identify both stimuli in a particular order, and order of report was compared between hands and across stimulus materials. Results indicated right-hand superiority for letters and left-hand superiority for lines; no hand differences occurred for digits. However, observed differences between hands appeared with second reports only, suggesting that measures of tactile storage are more sensitive to laterality differences than measures closer in time to actual stimulation.     

Effects of repeated retrieval on long-term retention in a nonverbal learning task in younger children

Many studies have shown the benefits for long term retention of repeated retrieval during learning in verbal tasks, but few have shown its effectiveness using nonverbal materials. The aim of this study was to examine whether the retention benefits of repeated retrieval extend to preschool children performing a spatial location memory task. In this task, the children first studied where eight small toys were located in a partitioned box. Then, in the repeated retrieval condition, the children were asked to put each one of the toys in its place by themselves three times successively with feedback, whereas in the repeated study condition, they were asked to put each toy in its place with the experimenter showing them the correct location. Half of the children were then immediately tested and the remaining half tested after one day. The results showed that the 5 and 6 year old children in the retrieval condition retained location memory for the toys longer than those in the study condition in a memory task involving spatial content and enactment components. These findings have deep theoretical implications for the critical role of retrieval effort in long-term retention, and highlight the efficacy of repeated retrieval for different developmental ages and tasks.     

Deception and truth detection when analyzing nonverbal and verbal cues

In this article, I present my view on the significant developments and theoretical/empirical tipping points in nonverbal and verbal deception and lie detection from the last 30 years and on prospects for future research in this domain. I discuss three major shifts in deception detection research: (a) From observing target persons' nonverbal behavior to analyzing their speech; (b) from lie detection based on differences between truth tellers and liars' levels of arousal to lie detection based on the different cognitive processes or strategies adopted to appear convincing; and (c) from passively observing target persons to actively interviewing them to elicit or enhance verbal cues to deceit. Finally, I discuss my ideas for future research, focusing on initiatives from my own lab. Hopefully, this will stimulate other researchers to explore innovative ideas in the verbal deception research domain, which already has seen so much progress in the last decade.