Learning your way around town: how virtual taxicab drivers learn to use both layout and landmark information

By having subjects drive a virtual taxicab through a computer-rendered town, we examined how landmark and layout information interact during spatial navigation. Subject-drivers searched for passengers, and then attempted to take the most efficient route to the requested destinations (one of several target stores). Experiment 1 demonstrated that subjects rapidly learn to find direct paths from random pickup locations to target stores. Experiment 2 varied the degree to which landmark and layout cues were preserved across two successively learned towns. When spatial layout was preserved, transfer was low if only target stores were altered, and high if both target stores and surrounding buildings were altered, even though in the latter case all local views were changed. This suggests that subjects can rapidly acquire a survey representation based on the spatial layout of the town and independent of local views, but that subjects will rely on local views when present, and are harmed when associations between previously learned landmarks are disrupted. We propose that spatial navigation reflects a hierarchical system in which either layout or landmark information is sufficient for orienting and wayfinding; however, when these types of cues conflict, landmarks are preferentially used.     

Narcissism and Cardiovascular Reactivity to Rejection Imagery1

This study examined the interactive effects of imagined rejection and narcissism on cardiovascular reactivity (CVR). Participants completed measures of overt narcissism (Narcissistic Personality Inventory, NPI; Raskin & Hall, 1979 ), overt–covert narcissism ( Margolis & Thomas, 1980 ), and trait self‐esteem. They then imagined 2 scenarios culminating in either interpersonal acceptance or rejection. Systolic (SBP) and diastolic blood pressure (DBP) and heart rate (HR) were assessed before, during, and after the imagery. Overt–covert narcissism was positively associated with task increases in SBP and DBP and recovery elevation of HR following rejection, but not acceptance. Similar effects on SBP were found for the Entitlement/Exploitativeness dimension of the NPI. Lower self‐esteem predicted greater task increases in SBP, DBP, and HR across conditions. Implications for health are discussed.     

Infants’ listening in multitalker environments: Effect of the number of background talkers

Infants are often spoken to in the presence of background sounds, including speech from other talkers. In the present study, we compared 5- and 8.5-month-olds’ abilities to recognize their own names in the context of three different types of background speech: that of a single talker, multitalker babble, and that of a single talker played backward. Infants recognized their names at a 10-dB signal-to-noise ratio in the multiple-voice condition but not in the single-voice (nonreversed) condition, a pattern opposite to that of typical adult performance. Infants similarly failed to recognize their names when the background talker’s voice was reversed—that is, unintelligible, but with speech-like acoustic properties. These data suggest that infants may have difficulty segregating the components of different speech streams when those streams are acoustically too similar. Alternatively, infants’ attention may be drawn to the time-varying acoustic properties associated with a single talker’s speech, causing difficulties when a single talker is the competing sound.     

Development and initial reliability and validity of a new measure of distorted maternal representations: The Mother–Infant Relationship Scale

Distorted maternal representations (DMRs)—mother's ideas, understanding, and feelings about the infant—shape early interaction and the emerging relationship. Distorted interactions reportedly affect infant attachment and socioemotional development and may be associated with maternal early adversity and trauma. Limited measures are available that could be used as screening tools of DMRs. The aims of this study were to (a) describe the development of the Mother–Infant Relationship Scale (MIRS) and (b) to evaluate its psychometric properties. The development and validation of the MIRS closely followed standard guidelines for the development of psychometric tests. Psychometric properties were examined across two samples: 78 adult psychiatric patients with features of borderline personality and 86 individuals from a nonclinical sample (N = 164). The scale demonstrated excellent internal consistency (Cronbach's α = .91) for the clinical sample and adequate internal consistency (.78) for the nonclinical sample, excellent test-retest reliability (intraclass correlation coefficient = .81), and good concurrent validity with an observational (Pearson's correlation coefficients = −.35 to −.54) and a representational measure (.53). Factor analysis revealed three components: DMRs specific to (a) maternal hostility/rejection of the infant, (b) issues about parenting/attachment, and (c) anxiety/helplessness about infant care. Findings suggest that the MIRS is a reliable and valid screening tool of DMRs. Potential uses in clinical and research settings are discussed.     

Making reference: The cohesive use of pronouns in the narrative discourse of hemidecorticate adolescents

The cohesive use of referential language in narrative production reveals communicative goals as well as specific aspects of language use. A formalism for analyzing pronominal cohesion was developed and applied to the narrative discourse of three hemidecorticate adolescents. The results revealed hemisphere-dependent differences in overall narrative skill as well as distinct individual discourse strategies. Neither left hemidecorticate planned narration in extended discourse units: One demonstrated a linear and highly explicit discourse style with redundant over-statement of referent nouns and the other produced narratives cluttered with pronouns of both correct and ambiguous reference, relying on nonpersonal pronouns at considerable cost to narrative specificity. The right hemidecorticate produced narratives that were more economical in form and richer in content: He was the only subject able to maintain simultaneous story lines with multiple pronouns and referential relationships cohesively embedded. All subjects expressed at least some story content, but only the right hemidecorticate narratives conveyed suggestion and implication as well as explicit statement.     

Self-management of a DRO procedure by three students with autism

Three students with autism were taught to self-manage a DRO program to reduce their disruptive behavior. During baseline conditions, all students showed high rates of disruptive behavior (either out-of-seat or nail-flicking). Students were taught to self-manage a DRO program during external reinforcement and prompted self-management conditions. Student gains were maintained during unprompted self-management and follow-up conditions. ©1997 John Wiley & Sons, Ltd.     

Self‐management of varied responding in three students with autism

One of the aspects of autism that is often held up as a hallmark of the disorder is a desire for sameness. Students with autism often show a marked lack of variability in language and play skills. The same behavioral patterns are repeated perseveratively, rather than attempting new patterns. In the current study, students diagnosed with autism were taught to self‐manage varied responding. Using a multiple baseline design, three children with autism were taught to self‐monitor and then to self‐manage in order to increase variability in play and social language. All three students demonstrated marked increases in variability during self‐management phases. These gains were maintained at one month follow‐up. Copyright © 2000 John Wiley & Sons, Ltd.