The purpose of the current study was to determine if self-reported lifetime marijuana use moderates the relationship between interleukin-6 (IL-6) and neurocognitive performance. Participants included 161 African American adults (50.3% women), with a mean age of 45.24 (SD=11.34). Serum was drawn upon entry into the study and participants completed a demographic questionnaire, which included drug use history, and a battery of neuropsychological tests. Using multiple regression analyses and adjusting for demographic covariates, the interaction term comprised of IL-6 and self-reported lifetime marijuana use was significantly associated with poorer performance on the Written (β=−.116; SE=.059; p=.049) and Oral trials (β=−.143; SE=.062; p=.022) of the Symbol Digit Modalities Test, as well as the Trail Making Test trial A (β=.157; SE=.071; p=.028). Current findings support previous literature, which presents the inverse relationship between IL-6 and neurocognitive dysfunction. The potential protective properties of marijuana use in African Americans, who are at increased risk for inflammatory diseases, are discussed. (JINS, 2014, 20, 773–783)

Objectives: A limited body of research is available on the relationships between multiplicity of birth and neuropsychological functioning in preterm children who were conceived in the age of assisted reproductive technology and served by the modern neonatal intensive care unit. Our chief objective was to evaluate whether, after adjustment for sociodemographic factors and perinatal complications, twin birth accounted for a unique portion of developmental outcome variance in children born at-risk in the surfactant era. Methods: We compared the neuropsychological functioning of 77 twins and 144 singletons born preterm (<34 gestational weeks) and served by William Beaumont Hospital, Royal Oak, MI. Children were evaluated at preschool age, using standardized tests of memory, language, perceptual, and motor abilities. Results: Multiple regression analyses, adjusting for sociodemographic and perinatal variables, revealed no differences on memory or motor indices between preterm twins and their singleton counterparts. In contrast, performance of language and visual processing tasks was significantly lower in twins despite reduced perinatal risk in comparison to singletons. Effect sizes ranged from .33 to .38 standard deviations for global language and visual processing ability indices, respectively. No significant group by sex interactions were observed, and comparison of first-, or second-born twins with singletons yielded medium effect sizes (Cohen’s d=.56 and .40, respectively). Conclusions: The modest twin disadvantage on language and visual processing tasks at preschool-age could not be readily attributable to socioeconomic or perinatal variables. The possibility of biological or social twinning-related phenomena as mechanisms underlying the observed performance gaps are discussed. (JINS, 2016, 22, 865–877)

Memory deficits are frequently observed in schizophrenia but their intrinsic characteristics have not been clarified. We studied remote memory in a group of 20 schizophrenics and 20 healthy age and education matched controls using a newly devised public event questionnaire (PEQ) that employs a free recall, progressive cueing and recognition protocol and requires dating of events. Results indicate that patients with chronic schizophrenia perform significantly more poorly on the PEQ than a group of age and education matched controls both in terms of content and dating of events. The number of events recalled does not improve with progressive cuing or recognition. No distinctive pattern was observed in their temporal gradient. There was no significant difference in content scores for pre- and post-onset events in the schizophrenics. These findings indicate that remote memory deficits in chronic schizophrenics arise from deficient encoding rather than from a retrieval deficit secondary to executive dysfunction. (JINS, 2002, 8, 861–866.)

Background: Verbal memory (VM) impairment is prominent in bipolar disorder (BD) and is linked to functional outcomes. However, the intricacies of VM impairment have not yet been studied in a large sample of BD patients. Moreover, some have proposed VM deficits that may be mediated by organizational strategies, such as semantic or serial clustering. Thus, the exact nature of VM break-down in BD patients is not well understood, limiting remediation efforts. We investigated the intricacies of VM deficits in BD patients versus healthy controls (HCs) and examined whether verbal learning differences were mediated by use of clustering strategies. Methods: The California Verbal Learning Test (CVLT) was administered to 113 affectively stable BD patients and 106 HCs. We compared diagnostic groups on all CVLT indices and investigated whether group differences in verbal learning were mediated by clustering strategies. Results: Although BD patients showed significantly poorer attention, learning, and memory, these indices were only mildly impaired. However, BD patients evidenced poorer use of effective learning strategies and lower recall consistency, with these indices falling in the moderately impaired range. Moreover, relative reliance on semantic clustering fully mediated the relationship between diagnostic category and verbal learning, while reliance on serial clustering partially mediated this relationship. Conclusions: VM deficits in affectively stable bipolar patients were widespread but were generally mildly impaired. However, patients displayed inadequate use of organizational strategies with clear separation from HCs on semantic and serial clustering. Remediation efforts may benefit from education about mnemonic devices or “chunking” techniques to attenuate VM deficits in BD. (JINS, 2017, 23, 358–366)

Emotional reactions are sometimes observed during the intracarotid sodium amobarbital test. For instance, euphoric/indifference reactions can be seen during right hemisphere inactivation and catastrophic reactions may accompany left hemisphere inactivation. Less dramatic changes can also be detected in affective self-report during left and right hemisphere amobarbital tests, with more negative affect reported during left hemisphere inactivation and either neutral or mildly positive affective states reported during right hemisphere inactivation. The current study not only replicated this effect, but in addition, found significant group differences. The first group (right way) showed a pattern of affective self-report during left and right amobarbital tests entirely consistent with prior findings, while a second group (wrong way) showed results that behaved in a diametrically opposite fashion. A third group (no change) showed little, if any, difference in affective self-report during left and right amobarbital tests. The major factor distinguishing the wrong way group from the other two appeared to be an asymmetrical distribution of left and right temporal lobe lesions in the former group. In contrast, the factor differentiating the right way group from the no change group appeared to be the relative degree of left hemisphere inactivation during the left hemisphere amobarbital test. The results are discussed not only in terms of their impact on theories of cerebral lateralization for emotion, but also in terms of methodological issues in this field. (JINS, 2000, 6, 659–667.)

It is still an open question whether short-term and long-term memory are two anatomically dissociable memory systems working in parallel or whether they are represented by neural circuits within similar cortical areas. Epilepsy may be used as a model to study these memory processes. We hypothesized that a double dissociation of short-term and long-term memory exists in temporal lobe epilepsy (TLE) and idiopathic generalized epilepsy (IGE). Immediate and 24-hour face recognition was tested in 10 TLE patients, 9 IGE patients, and 10 healthy controls. TLE patients’ immediate recognition was unimpaired, but their memory scores were reduced as compared to healthy controls after 24 hours. In IGE patients, memory was already reduced during immediate recognition. These results are in line with the idea that short-term memory is a transient trace that requires consolidation supported by the medial temporal lobe to change into a more stable status of long-term memory. (JINS, 2010, 16, 574–578.)

Objectives: To investigate whether the relationship between arm use and motor impairment post-stroke is influenced by the hemisphere of damage. Methods: Right-handed patients with unilateral left hemisphere damage (LHD) or right (RHD) (n=58; 28 LHD, 30 RHD) were recruited for this study. The Arm Motor Ability Test and Functional Impact Assessment were used to derive arm use patterns. The Fugl-Meyer motor assessment scale was used to quantify the level of motor impairment. Results: A significant interaction between patient group and impairment level was observed for contralesional, but not ipsilesional arm use. For lower impairment levels, contralesional (right arm for LHD and left arm for RHD) arm use was greater in LHD than RHD patients. In contrast, for greater levels of impairment, there were no arm use differences between the two patient groups. Conclusions: When motor impairment is significant, it overrides potential effects of stroke laterality on the patterns of arm use. However, a robust influence of hemisphere of damage on the patterns of arm use is evident at lower impairment levels. This may be attributed to previously described arm preference effects. These findings suggest adoption of distinct strategies for rehabilitation following left versus right hemisphere damage in right-handers, at least when the impairment is moderate to low. (JINS, 2019, 25, 470–478)

This study explored Closing-in behavior (CIB), the tendency in figure copying to draw very close to or on top of the model, in mild cognitive impairment (MCI). The files of 154 people diagnosed with MCI were reviewed and CIB was identified in 21% of cases. Two approaches were used to explore CIB. First, we capitalized on the diverse cognitive profiles within MCI, subdividing the overall sample into people with and without memory deficits. The frequency of CIB was significantly higher in multidomain non-amnestic MCI than in multidomain amnestic MCI, suggesting that CIB is not associated with specific memory impairment. Second, we assessed the cognitive correlates of CIB, by selecting patients with MCI who completed a battery of executive, visuo-constructional and memory tasks. Sub-groups of patients with and without CIB showed a similar overall severity of cognitive decline and comparable performance in visuo-constructional and memory tasks, but those with CIB were slightly but significantly more impaired on executive function tasks. The study provides evidence against memory-based accounts of CIB, and supports recent suggestions that executive impairments are the dominant cognitive correlate of this clinical sign. (JINS, 2012, 18, 269–276)

We investigated verb generation in children with spina bifida meningomyelocele (SBM; n = 55) and in typically developing controls (n = 32). Participants completed 6 blocks (40 trials each) of a task requiring them to produce a semantically related verb in response to a target noun and an additional 40 trials on which they were simply required to read target nouns aloud. After controlling for reading response time, groups did not differ significantly in verb generation response time or learning. Children with SBM produced more non-verb errors than controls and tended to repeat their mistakes over blocks. Verb generation performance was associated with brain volume measures in participants with SBM. Congenital cerebellar dysmorphology is associated with impaired performance in verb generation accuracy, although not with increased response times to produce verbs.(JINS, 2008, 14, 181–191.)