The cerebellum's role in cognitive skills was examined in a child (L.C.) with focal injury to the left cerebellum. Initial symptoms included aphasia and dysarthria. At 3 and 9 months post-injury, clinical neuropsychological tests revealed persistent psychomotor slowing as well as deficits in executive functions. Further cognitive testing at 13 and 16 months post-injury demonstrated that L.C. processed information from both the linguistic and nonlinguistic domains more slowly than age-, grade- and sex-matched controls. Notably, her linguistic processing was more than twice as slow as that of her peers, whereas her nonlinguistic processing was only approximately 20% slower. Within each domain the degree of cognitive slowing was approximately the same across diverse tasks. These results are consistent with the hypothesis of a cerebellar contribution to cognitive processing, particularly the processing of linguistic information. (JINS, 1998, 4, 491–501.)

Numerous reports have assessed the neuropsychological functioning of medically asymptomatic HIV-1 infected men. However, to date there have been no published studies of the neuropsychological functioning of asymptomatic HIV-1 infected women, even though women represent the fastest-growing demographic group of HIV-1 infected individuals. In this investigation, 31 women (17 asymptomatic HIV-1 seropositive, 14 seronegative) were administered a battery of neurocognitive and neuropsychiatric instruments. Participants in both groups were matched for age, education, months since injection drug use, and substance use. Group comparisons revealed no significant differences in any of the neurocognitive or neuropsychiatric measures. The results of this preliminary study suggest that clinically significant differences in neurobehavioral function are unlikely in medically asymptomatic HIV-1 infected women compared to seronegative controls. However, additional studies are needed with larger sample sizes and with careful attention to possible confounding or masking variables. (JINS, 1998, 4, 172–178.)

We report the results of a letter naming treatment designed to facilitate letter-by-letter reading in an aphasic patient with no reading ability. Patient M.R.'s anomia for written letters reflected two loci of impairment within visual naming: impaired letter activation from print (a deficit commonly seen in pure alexic patients who read letter by letter) and impaired access to phonology via semantics (documented in a severe multimodality anomia). Remarkably, M.R. retained an excellent ability to pronounce orally spelled words, demonstrating that abstract letter identities could be activated normally via spoken letter names, and also that lexical phonological representations were intact when accessed via spoken letter names. M.R.'s training in oral naming of written letters resulted in significant improvement in her oral naming of trained letters. Importantly, as M.R.'s letter naming improved, she became able to employ letter-by-letter reading as a compensatory strategy for oral word reading. M.R.'s success in letter naming and letter-by-letter reading suggests that other patients with a similar pattern of spared and impaired cognitive abilities may benefit from a similar treatment. Moreover, this study highlights the value of testing the pronunciation of orally spelled words in localizing the source of prelexical reading impairment and in predicting the functional outcome of treatment for impaired letter activation in reading. (JINS, 1998, 4, 595–607.)

A longitudinal case study of a patient with a progressive loss of meaning of objects with preserved phonology and syntax is presented. Repeated measures of language, praxis, visual cognition, and semantic processing were carried out. The patient still has preserved conversational speech, social skills, and orientation in her 8th year of her illness, but shows severe anomia and comprehension deficit in all modalities of stimulus presentation. In addition to standardized tests of language, cognition, and memory, specific experiments of categorization, modalities of word access, item consistency, category specificity, and definition of words were carried out. Results indicate a frequency dependent loss of meaning that was consistent in all modalities and throughout all object categories. However, the relative preservation of visual categorization of all categories tested and the language based categorization of animals suggested some fractionation of semantic memory. Relative preservation of autobiographical and personal memories versus semantic memory was a striking observation. Evidence for selective impairment of central semantic processing was obtained from experiments indicating item consistency of loss and the lack of semantic cuing. Neuroimaging evidence of left temporal lobe atrophy and the classical picture is compatible with similar cases published under the term semantic dementia or “transcortical sensory aphasia with visual agnosia” and suggest the diagnosis of Pick's disease. (JINS, 1998, 4, 388–398.)

Recognition memory for words and designs was assessed in epilepsy patients who underwent unilateral anterior temporal lobectomy. Memory was assessed during the intracarotid amobarbital test (IAT) performed prior to surgery and also following surgery. Memory discrimination and response bias lateralized differently. Memory discrimination, or memory accuracy, lateralized as a function of the type of material used in memory testing. Left temporal lobe lesions resulted in more impaired discrimination of verbal materials; right temporal lobe lesions resulted in more impaired discrimination of visuospatial materials. Response bias, the decision rule adopted in situations of uncertainty, was more liberal following left temporal lobe lesions for both verbal and visuospatial materials. Findings suggest that the two cerebral hemispheres are differentially specialized for encoding different types of information in long term memory, and that this impacts on decision strategies in situations of memory uncertainty. (JINS, 1998, 4, 502–511.)

The use of a mnemonic cueing system (NeuroPage®) and a paper and pencil checklist in the rehabilitation of executive problems in a 50-year-old woman are described. Following a CVA 7 years earlier, the patient, despite intact general intellectual and memory functioning, had specific executive impairments of attention, planning, realizing intended actions, and also exhibited behavioral routines similar in form to obsessive–compulsive rituals. In a series of ABAB single-case experimental designs, the efficacy of 2 external cueing systems in prompting appropriately timed action is demonstrated. It is argued that the combination of external control and increased sustained attention to action were critical to the success of NeuroPage with this patient. Furthermore it is hypothesized that the checklist was effective in facilitating the patient's ability to foresee and recognize the consequences of her actions, which in turn had an impact on the probability of her changing those same actions. (JINS, 1998, 4, 399–408.)

While the neuropsychological literature includes few cases of child-onset amnesia, 2 previous case studies suggest that these patients may be able to learn new information of a semantic or academic nature. The previous studies were, in large part, based on neuropsychological testing performed during adulthood and a retrospective review of academic achievement test scores during childhood. We present patient A.C., who acquired severe anterograde amnesia at age 10 years but demonstrated average levels of performance on tests of reading, spelling and arithmetic upon examination at age 19 years. Episodic and semantic memory test scores were severely impaired, but near normal performances were found on tests of implicit and procedural memory. In a prospective study, A.C. learned to read new irregular and pseudowords and retained this learning over a 1-month period, similar to the performance of age-matched controls. This demonstration of postmorbid, acquired oral reading vocabulary supports a previous conclusion that oral reading can progress in childhood following the onset of severe anterograde amnesia. The data also suggest that this new learning probably reflects nondeclarative memory processes rather than preservation of semantic memory, as was proposed in an earlier case study. (JINS, 1998, 4, 179–189.)

Phonological alexia and agraphia are acquired disorders characterized by an impaired ability to convert graphemes to phonemes (alexia) or phonemes to graphemes (agraphia). These disorders result in phonological errors typified by adding, omitting, shifting, or repeating phonemes in words during reading or graphemes when spelling. In developmental dyslexia, similar phonological errors are believed to result from deficient phonological awareness, an oral language skill that manifests itself in the ability to notice, think about, or manipulate the individual sounds in words. The Auditory Discrimination in Depth (ADD) program has been reported to train phonological awareness in developmental dyslexia and dysgraphia. We used a multiple-probe design to evaluate the ADD program's effectiveness with a patient with a mild phonological alexia and mixed agraphia following a left hemisphere infarction. Large gains in phonological awareness, reading and spelling nonwords, and reading and spelling real words were demonstrated. A follow-up reassessment, 2 months posttreatment, found the patient had maintained treatment gains in phonological awareness and reading, and attained additional improvement in real word reading. (JINS, 1998, 4, 608–620.)

This study describes changes in cognitive function in patients who are typically excluded from longitudinal studies due to their inability to complete most standardized batteries. Thirty-three patients with moderate to severe Alzheimer's disease were assessed by means of the Severe Impairment Battery (SIB), Mini Mental State Examination (MMSE), Clinical Dementia Rating (CDR), and measures of functional status. Follow-up evaluations were conducted, and annual rates of change were calculated. Patients with severe cognitive impairment demonstrated rates of progression similar to patients who were moderately impaired at initial evaluation. Rates of decline on the SIB were unrelated to baseline cognitive function, and annual rate of decline in Year 1 was not correlated with disease progression in the subsequent year. This study demonstrates that, with appropriate assessments, severely impaired patients can exhibit a range of performance and rates of decline that are comparable to those of moderately impaired patients. (JINS, 1998, 4, 512–516.)

Two individuals with anomic aphasia and acquired alexia were each provided treatment for their reading impairment. Although reading of single words in isolation was fairly accurate, their text reading was slow and effortful, including functor substitutions and semantic errors. Prior to treatment, reading reaction times for single words showed grammatical class and word-length effects. Both patients responded positively to a treatment protocol that included two phases: (1) multiple oral rereading of text, and (2) reading phrase-formatted text that had increased spacing between phrasal clauses. Their reading rates for text improved while maintaining good comprehension. Following treatment, reading reaction times for single words showed the elimination of grammatical class and word-length effects, suggesting improved access to word forms, particularly functors. (JINS, 1998, 4, 621–635.)

Fortunately, it is the rare neuropsychologist who still uses the term “frontal lobe functions” to refer to the collection of supervisory and regulatory mental processes we now typically call the “executive functions.” Most of us have come to realize that simply using a neuroanatomic moniker for a set of cognitive processes does not a neuropsychology make.

Recently an outbreak of acute respiratory infection associated with the hantavirus occurred in the southwestern United States. Hantavirus pulmonary syndrome (HPS) is a life threatening illness that carries with it a high mortality rate. Patients with HPS experience prolonged periods of hypoxemia requiring mechanical ventilation and treatment in intensive care units. We have recently seen 2 survivors of HPS. A neuropsychological test battery was administered immediately following their acute hospitalization and at 1 year postrecovery from HPS. Both patients exhibited cognitive impairments immediately following HPS as well as persistent cognitive impairments at 1 year. The cognitive impairments seen in these two HPS survivors are similar to those seen in other patients who have experienced brain anoxia, including memory impairments. It is also possible that hantavirus may directly cause brain injury with concomitant cognitive impairments. Additional research needs to be carried out in order to determine the extent and severity of the cognitive impairments in survivors of HPS. (JINS, 1998, 4, 190–196.)

In their dialogue published in JINS, Wilson (1997) and Prigatano (1997) have eloquently and concisely presented the challenges facing neuropsychology with respect to cognitive rehabilitation. However, both authors neglect two important issues that must be addressed if people with cognitive disorders are to be effectively treated. First, cognitive impairment must be treated during the acute stages of recovery; as to ignore cognitive deficits until patients are more fully recovered may bypass an opportune time for intervention. Evidence is mounting that the injured brain adapts to the losses sustained and that the adaptation will be enhanced by increasing interaction with the environment, as compared to more passive states (Johansson & Ohlsson, 1996; Stein et al., 1995). Given such information, it is difficult to justify withholding cognitive stimulation and remediation from people during acute stages of recovery and instead awaiting a point when spontaneous recovery (presumably) will be complete.

In this article I critically review the concept of the central executive. I argue that the experimental evidence for a central executive lacks rigor to the point where it is an unfalsifiable construct. I examine the neuropsychological and neuroradiological evidence and demonstrate that there is no localization evidence for a central executive. What emerges instead is a pattern of extensive heterogeneity with different executive tasks associated with different neural substrates. In sum it is argued that the idea of a central executive should be abandoned, and, from a neuropsychological perspective, tests that purport to measure executive function should do so in a qualitative way rather than assume that a range of tests load on a unitary dimension of performance. (JINS, 1998, 4, 518–522.)

We present a case study of a 43-year-old woman with chronic and stable pure alexia. Using a multiple baseline design we report the results of two different interventions to improve reading. First, a restitutive treatment approach using an implicit semantic access strategy was attempted. This approach was designed to exploit privileged access to lexical–semantic representations and met with little success. Treatment was then switched to a substitutive treatment strategy, which involved using the patient's finger to pretend to copy the letters in words and sentences. Reading using this motor cross-cuing strategy was 100% accurate and doubled in speed after 4 weeks of intervention. We propose that this patient's inability to benefit from the implicit semantic access treatment approach may be in part related to her inability to suppress the segmental letter identification process of word recognition. (JINS, 1998, 4, 636–647.)

I report a series of single case studies involving an aphasic patient, H.G., which illustrates both the usefulness and the limitations of cognitive neuropsychological models and methods in aphasia rehabilitation. The first set of experiments analyze H.G.'s pattern of performance across lexical tasks in order to identify the loci of her damage to the cognitive mechanisms underlying the tasks of naming, comprehension, repetition, reading, and spelling. The second set of studies evaluates her response to two different types of treatment and identifies a few of the variables that influence the effectiveness of treatment. (JINS, 1998, 4, 648–660.)

Parkin's criticisms of the central executive are based on a series of misconceptions. The central executive is not an organ that might or might not exist, but a scientific concept. Part of its function is to separate the analysis of executive processes from the question of their anatomical location. Like other components of working memory, it is fractionable into subsystems. How the subsystems interrelate and how they map onto the anatomical substrate are empirical questions under active current investigation. (JINS, 1998, 4, 523–526.)