Psychological functioning after severe closed head injury

The residual effects of severe closed head injury on psychological functioning, as determined by data from the Rorschach test, were examined. Thirty-five young adult patients with severe closed head injury were compared to a nonpatient, non-head injured matched group sample of 36 subjects. The utility of the Rorschach test in distinguishing the characteristic psychological functioning of inpatients who have suffered from severe closed head injury was outlined. The apperceptive disturbance, affective/cognitive problems, and interpersonal difficulties were discussed.     

Question-asking strategies after severe closed head injury.

This investigation examined problem solving behaviors in survivors of severe closed head injury. Fourteen patients and 10 neurologically intact controls were administered the Twenty Questions procedure, requiring them to guess items the examiner was thinking of in a picture array. Relative to controls, survivors required more trials to guess the items and utilized a strategy characterized by attention to the individual pictures rather than to their shared conceptual features. The importance of problem solving impairments to neurobehavioral outcome after head injury is discussed.     

Automatic and effortful processing after severe closed head injury

To investigate the automatic versus effortful distinction following severe closed head injury (CHI), we administered free recall and frequency of occurrence tasks to patients and controls. In Experiment 1 we found that both free recall (an effortful task) and judgment of relative frequency of occurrence (an automatic task) were impaired in 15 CHI patients as compared to 14 controls. In Experiment 2 we corroborated this finding and showed that absolute estimates of frequency were also impaired in new samples of 16 patients and 16 controls. We infer that cognitive tasks which normal individuals can perform without practice, feedback, or instructions may demand more effortful strategies following severe CHI.     

Neuropragmatics: extralinguistic communication after closed head injury

This work is concerned with the decay of communicative abilities after head trauma. A protocol composed of 16 videotaped scenes was devised in order to investigate the comprehension of several types of communicative actions realized with extralinguistic means, like pointing or clapping. The protocol was administered to 30 closed-head-injured individuals. The results showed that performance decreased from simple standard acts to complex standard acts, deceits, and ironies. The subjects' performance was worse with the scenes reproducing failing, rather than successful, communicative actions. The results are compared with those we previously obtained with a linguistic protocol. A theory of the cognitive processes underlying intentional communication is outlined and used to explain the results.     

Linguistic recovery after closed head injury

Recovery from acute aphasia after closed head injury was studied in 21 young adults at least 6 months after injury. Three profiles of scores were found using standardized language tests. Persistent expressive and receptive impairment was present in 6 patients who sustained severe diffuse brain injury resulting in global cognitive deficit. Residual expressive impairment, primarily of naming, was associated with mild diffuse brain injury though focal left-hemisphere injury was present in 3 of 6 cases. Patients who recovered to normal levels on all language tests generally had acute neurologic findings consistent with mild diffuse brain injury. Cranial computed tomography at the time of followup frequently disclosed ventricular enlargement.     

Speed of processing within semantic memory following severe closed head injury.

This study investigated the effects of severe closed head injury (CHI) on the speed of information processing within semantic categories. The question of whether subjects were able to benefit from priming was also investigated. Survivors of severe CHI who were less than 1 year postinjury and survivors who were greater than 1 year postinjury were compared with neurologically normal matched controls utilizing a category judgement task. The results demonstrated slower processing within semantic memory for both groups of CHI patients compared to normal controls. Furthermore, individuals with CHI were able to benefit from priming to the same relative degree as control subjects. Overall, the results suggested semantic organization remains intact after severe CHI, but accessing semantic information is slowed.     

Referential cohesion and logical coherence of narration after closed head injury

A group with closed head injury was compared to neurologically intact controls regarding the referential cohesion and logical coherence of narrative production. A sample of six stories was obtained with tasks of cartoon-elicited story-telling and auditory-oral retelling. We found deficits in the clinical group with respect to referential cohesion, logical coherence, and accuracy of narration. The occurrence of deficits depended on the condition of narrative production and, to some extent, on the particular story used. The primary implications of this study pertain to the attention given by researchers to the feature of discourse production being studied and processing demands of the task.     

Narrative discourse after closed head injury in children and adolescents.

This study examined narrative discourse in 20 children and adolescents at least 1 year after sustaining a head injury. Narratives were analyzed along the dimensions of language structure, information structure, and flow of information. Severity of impaired consciousness was associated with a significant reduction in the amount of language and information. The most important finding which emerged was the disruption in information structure. This pattern confirms the impression of disorganized discourse in severely injured children. Explanations for the disruption in information structure are explored in terms of the role of vocabulary, memory, and localization of lesion according to magnetic resonance imaging. In view of recent evidence that frontal lobe damage is associated with discourse formulation deficits in adults and is the most common site of focal lesion in closed head injury, we examined discourse patterns in individual patients with frontal lobe lesions. Preliminary data from our single-case studies suggest discourse patterns similar to those reported for adults with frontal lobe injuries.     

Actual versus self-reported scholastic achievement of litigating postconcussion and severe closed head injury claimants

Psychologists typically rely on patients' self-report of premorbid status in litigated settings. The authors examined the fidelity between self-reported and actual scholastic performance in litigating head injury claimants. The data indicated late postconcussion syndrome (LPCS) and severe closed head injury litigants retrospectively inflated scholastic performance to a greater degree than nonlitigating control groups. The LPCS group showed the highest magnitude of grade inflation, but discrepancy scores did not significantly correlate with a battery of malingering measures or with objective cerebral dysfunction. These findings support previous studies, which showed self-report is not a reliable basis for estimation of preinjury cognitive status. Retrospective inflation may represent a response shift bias shaped by an adversarial context rather than a form of malingering.     

The relationship between post-trauma problem reporting and carer quality of life after severe head injury

Abstract

Head injury is a significant cause of death and disability. This study examined the quality of life of carers of individuals following severe head injury from the acute neurosurgical care period to one year post discharge from hospital. The contribution of patterns of problem reporting by patients and their carers to quality of life was examined. Carer psychosocial adjustment and individual quality of life evaluations were significantly poorer than general population levels and did not change over a one year period. However, significant increases in the number of problems reported were noted over time. No significant differences were found between patients and carers in the numbers of problems identified at each of three assessments, although the level of agreement about problems identified was quite low. Female patients reported significantly more problems than male patients. Carer problem reporting was found to significantly predict carer quality of life and psychosocial functioning to a greater extent than patient problem reporting, a pattern which emerged after the patient had been discharged from hospital. The study demonstrates increasing problem profiles and differing perceptions of patients and carers over time. Combined with a lack of improvement in carer quality of life over a one year recovery period, this highlights the need for longer-term professional support and advice services aimed at both patients and carers.     

Divided attention enhances the recognition of emotional stimuli: evidence from the attentional boost effect

The present study examined predictions of the early-phase-elevated-attention hypothesis of the attentional boost effect (ABE), which suggests that transient increases in attention at encoding, as instantiated in the ABE paradigm, should enhance the recognition of neutral and positive items (whose encoding is mostly based on controlled processes), while having small or null effects on the recognition of negative items (whose encoding is primarily based on automatic processes). Participants were presented a sequence of negative, neutral and positive stimuli (pictures in Experiment 1, words in Experiment 2) associated to target (red) squares, distractor (green) squares or no squares (baseline condition). They were told to attend to the pictures/words and simultaneously press the spacebar of the computer when a red square appeared. In a later recognition task, stimuli associated to target squares were recognised better than stimuli associated to distractor squares, replicating the standard ABE. More importantly, we also found that: (a) the memory enhancement following target detection occurred with all types of stimuli (neutral, negative and positive) and (b) the advantage of negative stimuli over neutral stimuli was intact in the DA condition. These findings suggest that the encoding of negative stimuli depends on both controlled (attention-dependent) and automatic (attention-independent) processes.     

Planning times during traveling salesman's problem: differences between closed head injury and normal subjects

We studied planning behavior in a group of normal subjects and a group of closed head injury patients (CHI). A computerized version of the traveling salesman's problem was used as a visuospatial planning ability task. The program collected measurements of partial times, number of moves, and number of skipped subgoals. These measures allow us to calculate a "planning index" of subjects' planning ability. Results show that CHI patients present limitations in the planning process due to the lack of ongoing planning.     

Successful treatment of stuttering following closed head injury

Based on a review of the literature, sudden onset of stuttering following a closed head injury has generally had a prognosis of poor recovery. The present case study of an adult male reviews the relevant neurologic data, psychologic information, and subsequent speech therapy methods used to facilitate an essentially complete recovery of normal speech within a few months. A possible neurologic explanation for the stuttering behavior and associated factors in recovery is discussed.     

Exploration of head injury without medical attention.

In surveys of prison inmates and four other populations, 1,055 subjects reported having a history of 489 head injuries, with 31% of these "unattended" by a physician and 60% "undocumented" in that they were not hospitalized. The prison inmates did not have a history of more unattended injuries or undocumented injuries than the other groups of subjects as was predicted. However, the inmates reported more permanent effects from their unattended and undocumented injuries. Also, the inmates had more permanent effects and longer unconsciousness than did the other groups for their attended and documented head injuries.     

Divided attention between lyrics and tunes of operatic songs: Evidence for independent processing

Excerpts from French operatic songs were used to evaluate the extent to which language and music compete for processing resources. Do these two dimensions conflict? Are they integrated into a single percept? Or are they independent? The final word of each excerpt was either semantically congruous or incongruous relative to the prior linguistic context and was sung either in or out of key. Participants were asked to detect either the semantic or the melodic incongruity (single task) or both (dual task). We predicted a dual-task deficit if these tasks conflicted and no deficit if they were either independent or integrated. In order to distinguish between these last two outcomes, trial-by-trial contingency analyses were also computed, predicting no correlation if the tasks were conflicting or independent, a positive correlation under the assumption of integration and a negative correlation if dividing attention is impossible. Our results show similar levels of performance in single and dual tasks and no correlation between dual-task judgments, thus suggesting that semantic and melodic aspects of language are processed by independent systems. In addition, a comparison between musicians and nonmusicians shows that these conclusions are independent of musical expertise.     

Divided attention between lyrics and tunes of operatic songs: evidence for independent processing.

Excerpts from French operatic songs were used to evaluate the extent to which language and music compete for processing resources. Do these two dimensions conflict? Are they integrated into a single percept? Or are they independent? The final word of each excerpt was either semantically congruous or incongruous relative to the prior linguistic context and was sung either in or out of key. Participants were asked to detect either the semantic or the melodic incongruity (single task) or both (dual task). We predicted a dual-task deficit if these tasks conflicted and no deficit if they were either independent or integrated. In order to distinguish between these last two outcomes, trial-by-trial contingency analyses were also computed, predicting no correlation if the tasks were conflicting or independent, a positive correlation under the assumption of integration and a negative correlation if dividing attention is impossible. Our results show similar levels of performance in single and dual tasks and no correlation between dual-task judgments, thus suggesting that semantic and melodic aspects of language are processed by independent systems. In addition, a comparison between musicians and nonmusicians shows that these conclusions are independent of musical expertise.     

Divided attention enhances explicit but not implicit conceptual memory: an item-specific account of the attentional boost effect

The Attentional Boost Effect (ABE) refers to the counterintuitive finding that words encoded with to-be-responded targets in a divided-attention condition are remembered better than words encoded with distractors. Previous studies suggested that the ABE-related enhancement of verbal memory depends upon the activation of abstract lexical representations. In the present study, we extend this hypothesis by embedding it in the context of a broader perspective, which proposes that divided attention in the ABE paradigm affects item-specific, but not relational, processing. To this purpose, we examined the ABE in the matched tasks of category-cued recall (CCRT: explicit memory) and category exemplar generation (CEGT: implicit memory). In addition, study time was varied (500, 1500 or 4000?ms), to further determine whether the attentional boost manipulation could influence late-phase elaborative processing. In agreement with the predictions of the item-specific account, the results showed that exemplars encoded with targets were recalled better than exemplars encoded with distractors in the CCRT, but not in the CEGT. Moreover, performance in the CCRT increased with study time, whereas the size of the ABE-related enhancement tended to decrease, further confirming that this effect hinges upon early phase encoding processes.     

Divided attention: the whole is more than the sum of its parts

A divided attention situation is more than the sum of its component single tasks. Emergent aspects of the whole situation must also be considered. Three examples illustrate this. (a) When several complex stimuli (e.g., letters) are identified at once, their perceived components or features must be appropriately bundled together. Otherwise, components of two different stimuli may appear combined. This (emergent) problem is shown to depend on attention to multiple stimuli, not simply their presentation. (b) In the psychological refractory period (PRP) situation, especial difficulties arise when stimulus-response mappings are different for first and second reactions. It appears that for each reaction there is some (emergent) uncertainty over which mapping to use. This is only one of many possible emergent processes in the PRP situation. (c) When the two hands perform different actions (internally programmed sequences of taps), there is some tendency for each hand to carry out the action assigned to the other. This again is only a small part of the (emergent) problem of motor coordination. Thus the simple idea of competition for limited resources captures only a part of the problem of divided attention. Performance under divided attention will reflect an interaction between resource limitation, single task processes, and emergent aspects of the whole situation.     

Attributions of behavior in the pediatric mild closed head injury (CHI) population

Forty-one children between the ages of 6 and 11 years with a history of a mild closed head injury and 23 age-, gender-, and IQ-matched typically developing control children participated. All of the children in the CHI sample were referred for a magnetic resonance imaging (MRI) scan at 3 months post-injury and children in the CHI sample were further divided into MRI-Negative (n=31) and MRI-Positive (n=10) conditions according to the MRI results. Parents and teachers completed behavioral checklists at three points, including just prior to the MRI and 6 months post-injury. Prior to the MRI (Time 2), in both samples of children with a CHI, parents reported an increase in externalizing symptoms after the CHI. At 6 months post-injury (Time 3: post-MRI), parents of children in the MRI-Positive group did not report any significant changes in their child's externalizing behaviors when compared with pre-MRI, yet parents of children in the MRI-Negative group reported a further increase in externalizing behaviors. Parent attributions also changed as a function of group membership; whereas no changes were noted in the other two groups, parents of children in the MRI-Negative sample ascribed more controllability at Time 3 when compared with Time 2.     

Dissociations and dependencies between speed and accuracy: Evidence for a two-component theory of divided attention in simple tasks

Previous work has amply demonstrated divided attention “costs” both in single-task multistimulus visual processing and in performance of multiple simple tasks; however, the relationship between the two has not been clarified. This article postulates two distinct causes: (1) visual processes that commence without delays and proceed simultaneously, but show lingering mutual interference dependent upon complexity, and (2) discrete queueing of the response selection stage. The first has resource-like properties, while the second has bottleneck-like properties. Either or both can generate performance costs observed in any particular situation, accounting for a variety of previous results. To test this theory, the effects of stimulus onset asynchrony (SOA) on accuracy and speed in performing dual choice tasks were examined. The first two experiments involved a choice response to a tone as a first task, and a second task requiring complex perceptual decisions (digit identification or conjunction search) with masked displays and unspeeded second responses. Reducing the SOA had negligible effects upon second-task accuracy, and performance in the two tasks was virtually independent. However, when speeded manual (Exp. 3) or vocal (Exp. 4) responses were required on the same second task, dramatic interference was observed, with strong positive dependencies between reaction times (RTs) on the two tasks. When both tasks involved complex visual displays, SOA reductions produced dramatic interference, but no dependencies between performance, whether the first task involved a speeded (Exp. 5) or unspeeded (Exp. 6) response. The results reject pure late-selection accounts and general capacity sharing models, and support the two-component theory. They also suggest that standard use of the term “attention,” suggesting a single resource or mechanism, is highly misleading.