Obstructive sleep apnea (OSA) is a nocturnal respiratory disorder associated with cognitive and behavioral sequelae, including impairments in executive functioning (EF). Previous literature has focused on “cool” EF, meaning abilities such as working memory and planning that do not involve affective control requirements. Little is known about the impact OSA may have on “hot” EF that involves regulation of affect and risk-related decision-making, and that may be particularly salient during adolescence, when these skills are rapidly developing. This study examined performance on the Iowa Gambling Task (IGT), a task believed to assess aspects of “hot” EF, in overweight adolescents at risk for OSA. Consistent with hypotheses, individuals without OSA made more beneficial decisions on the IGT over time, but participants with OSA did not benefit from feedback and continued to make choices associated with higher initial rewards, but greater long-term losses. The relationship between developmental level and IGT performance was moderated by OSA status. Individuals with OSA did not demonstrate the expected developmental gains in performance during the IGT. This finding suggests that OSA may impact the development of critical aspects of EF, or at least the expression of these skills during the developmentally important period of adolescence. (JINS, 2012, 18, 481–489)

We hypothesized that patients with bipolar disorder would demonstrate verbal recognition performance deficits consistent with processing efficiency theory, a theory about how emotional states modulate performance by interfering with working memory resources or increasing cognitive arousal/effort. We predicted that (1) a manic group (n = 26) would demonstrate slow reaction time (RT) and low accuracy, (2) a euthymic group (n = 23) would demonstrate slow RT to maintain high accuracy; and (3) a healthy comparison group (n = 25) would demonstrate fast RT and high accuracy. The groups were administered symptom-rating scales and compared on a computerized, trial-by-trial, directed forgetting in recognition task. This task requires participants to comply with an overt instruction to forget irrelevant studied words, and it places a relatively high demand on working memory. The manic group was impaired on directed-forgetting sensitivity; however, when RT was statistically controlled, the groups demonstrated similar directed-forgetting effects. These findings are consistent with processing efficiency theory. They suggest that bipolar patients perform directed forgetting in recognition by increasing effortful control at encoding at the expense of processing efficiency, although acute mania reduces the capacity for control, thereby impairing recognition performance. Problems with processing efficiency are viewed as trait characteristics of bipolar disorder that may be overlooked by traditional error-based assessments. (JINS, 2005, 11, 871–880.)

Ecstasy (MDMA) is a popular drug that can act as a selective serotonin neurotoxin in several species. The goal of the present study was to examine the relationship between ecstasy exposure and cognitive functioning after controlling for other drug use and demographic variables. Furthermore, we assessed whether gender was a moderator of the relationship between cognitive functioning and ecstasy use. Data were collected from 31 men and 34 women with a wide range of ecstasy use (17 marijuana users with no ecstasy use and 48 ecstasy users ranging from low to heavy use). Participants were interviewed and administered a battery of neuropsychological tests. The primary finding was that ecstasy exposure was significantly related to poorer verbal learning and memory ability in a dose-dependent manner, while no such relationship was observed between ecstasy exposure and executive functioning or attentional ability. Gender was found to significantly moderate the relationship between ecstasy consumption and design fluency. These results suggest primary memory dysfunction among abstinent recreational ecstasy users. This finding is consistent with reports of hippocampal vulnerability, particularly among heavy users. (JINS, 2005, 11, 753–765.)

Bipolar disorder (BPD) is a severe psychiatric illness that is characterized by episodes of extreme mood states. The affective components of bipolar disorder have been studied extensively, but only recently have investigators begun to systematically examine its cognitive concomitants. Although executive dysfunction has been reported in this population, especially while patients are manic, the tasks administered in many previous studies have made it difficult to determine the specific executive abilities that were compromised. The present study examined 15 patients with bipolar disorder who were manic, 18 who were euthymic, and 18 healthy participants. Tests were selected to evaluate two specific aspects of executive functioning in these participants. The Object Alternation Task was given as a measure of inhibitory control, and the Delayed Response Task was included as a measure of spatial delayed working memory. All groups performed similarly on the Delayed Response Task. On the Object Alternation Task, however, the manic and euthymic patients committed significantly more perseverative errors than healthy participants. These results indicated that patients in the present sample had relatively normal working memory abilities, but had a deficit in behavioral self-regulation, which was evident across mood states. (JINS, 2005, 11, 163–172.)Location of work: Center for Bipolar Disorders Research, Department of Psychiatry, University of Cincinnati School of Medicine, Cincinnati, Ohio.

We hypothesized that patterns of sustained attention performance in bipolar disorder were consistent with processing efficiency theory—a theory of the relationship between central processing capacity and performance. We predicted (1) sustained attention deficits during mania because symptoms interfere with limited-capacity executive control processes resulting in decreased performance effectiveness; and (2) decreased processing efficiency during euthymia, as indicated by speed/accuracy tradeoffs, consistent with a stable phenotypic abnormality. Twenty-five manic bipolar, 23 euthymic bipolar, and 28 healthy comparison participants were compared on a continuous performance task and administered symptom-rating scales. The manic group was significantly impaired on overall perceptual sensitivity and demonstrated a significant linear decrease in performance over time, consistent with impaired sustained attention. The euthymic group evidenced significantly slower overall hit reaction time (RT), but when RT was controlled they performed similarly to the healthy group over time. Two discriminant functions combined to separate the groups on manic symptom severity and on-task effort/strategy use. These findings are consistent with processing efficiency theory. They suggest that euthymic patients sustain attention through effortful control at the expense of processing efficiency, while acute mania reduces the capacity for control and impairs sustained attention. Problems with processing efficiency are viewed as trait characteristics of bipolar disorder that may be overlooked by traditional error-based assessments. (JINS, 2005, 11, 49–57.)

Patients diagnosed with bipolar disorder (BPD), by definition, have problems with emotional regulation. However, it remains uncertain whether these patients are also deficient at processing other people's emotions, particularly while manic. The present study examined the ability of 25 manic bipolar patients and 25 healthy participants on tasks of facial recognition and facial affect recognition at three different presentation durations: 500 ms, 750 ms, and 1000 ms. The groups did not differ in terms of age, education, sex, ethnicity, or estimated IQ. The groups did not differ significantly on either a novel computerized facial recognition task or the Benton Facial Recognition Test. In contrast, the bipolar group performed significantly more poorly than did the comparison group on a novel facial affect labeling task. Although the patient group had slower reaction times on all 3 computerized tasks, the presentation duration did not have an effect on performance in the patients. This study suggests that patients with bipolar disorder are able to recognize faces, but have difficulty processing facial affective cues. (JINS, 2003, 9, 623–632.)

Neuroimaging and lesion studies have demonstrated that hippocampal volume correlates with memory performance, but material-specific lateralization of this structure-function relationship has been inconsistent. This MRI study examined the relative contributions of left and right temporal lobe volumes to verbal and nonverbal recognition memory in a group of 20 Alzheimer's disease (AD) patients. There was a significant relationship between extent of right hippocampal and right temporal gray matter tissue volume deficit and performance on the face recognition subtest of the Warrington Recognition Memory Test. The face recognition test correlated with right hemisphere volume but not to left, indicating a material-specific relationship between brain structure and function in this patient group. Right temporal horn volume did not account for a significant proportion of variance in face recognition memory. Although word recognition was not significantly correlated with either left or right hippocampal volume in the total group, there was a strong correlation between left hippocampal volume and word recognition memory in the female AD patients. Thus, face recognition shows a material specific relationship with select lateralized hippocampal and temporal cortical volumes in AD patients, regardless of gender, whereas the verbal recognition–left-hippocampal volume relationship may be mediated by gender. (JINS, 1998, 4, 106–114.)

This study examined the relationships between regional cortical and hippocampal brain volumes and components of remote memory (recall, recognition, sequencing, and photo naming of presidential candidates) in 13 individuals with Alzheimer's disease (AD). Recognition and sequencing of remote memory for public figures were associated with regional cortical volumes. Specifically, lower recognition and sequencing scores were associated with smaller parietal–occipital cortical volumes; poorer sequencing was also associated with smaller prefrontal cortical volumes. By contrast, poorer anterograde but not remote memory scores were correlated with smaller hippocampal volumes. Within the constraints of the brain regions measured, these findings highlight the importance of the posterior cortical areas for selective remote memory processes and provide support for the dissociation between cortically mediated remote memory and hippocampally mediated anterograde memory. (JINS, 2001, 7, 384–390.)

The Clock Drawing Test (CDT) is widely used in the assessment of dementia and is known to be sensitive to the detection of deficits in neurodegenerative disorders such as Alzheimer's disease (AD). CDT performance is dependent not only on visuospatial and constructional abilities, but also on conceptual and executive functioning; therefore, it is likely to be mediated by multiple brain regions. The purpose of the present study was to identify component cognitive processes and regional cortical volumes that contribute to CDT performance in AD. In 29 patients with probable AD, CDT performance was significantly related to right-, but not left-hemisphere, regional gray matter volume. Specifically, CDT score correlated significantly with the right anterior and posterior superior temporal lobe volumes. CDT scores showed significant relationships with tests of semantic knowledge, executive function, and visuoconstruction, and receptive language. These results suggest that in AD patients, CDT performance is attributable to impairment in multiple cognitive domains but is related specifically to regional volume loss of right temporal cortex. (JINS, 1999, 5, 502–509.)

Although mesial temporal lobe brain damage is frequently associated with memory loss, it is unclear whether the deficit results entirely from a disruption in the processing of relevant information or whether it also reflects interference from irrelevant information. Directed forgetting is one procedure that can be used, along with standard tests of memory, to investigate this distinction. Seventeen patients with a diagnosis of complex–partial seizures of temporal lobe origin and 17 healthy volunteers were compared on lexical decision, free recall, and recognition tests in a directed-forgetting paradigm. These tests created a memory profile to measure the influence of task relevant and irrelevant information in implicit and explicit memory. Compared with healthy volunteers, the patients were significantly impaired on the memory tasks overall [F(5,25) = 5.01, p < .01]. Specifically, directed forgetting in lexical decision and recognition both discriminated between the groups [stepdown F(1,26) = 6.84, η2 = .26, p < .05 and stepdown F(1,25) = 5.36, η2 = .13, p < .05, respectively]. The results suggest that interictal memory performance in temporal lobe epilepsy may be disrupted in part because of a deficit in the differential processing of task relevant and task irrelevant information, particularly at retrieval. (JINS, 1999, 5, 549–555.)