Elliott D. Ross

Left‐handed mirror writing following right anterior cerebral artery infarction Evidence for nonmirror transformation of motor programs by right supplementary motor area

A patient with acquired, pathologic left-handed mirror writing and mirror movements during bimanual coordination is reported. CT demonstrated an ischemic infarction involving the right supplementary motor area, medial prefrontal cortex, and anterior cingulate gyms with nearly total sparing of the corpus callosum. This case, together with recent experimental findings in monkeys, supports the hypothesis that the supplementary motor area may be responsible for nonmirror transformation of motor programs originating in the left hemisphere prior to execution by the primary motor area in the right hemisphere.

Localization of the pyramidal tract in the internal capsule by whole brain dissection

Six human brains were dissected by blunt technique and sectioned horizontally to establish the three-dimensional relationships of the pyramidal tract and the internal capsule. In all instances, the pyramidal tract entered the rostral capsule in the anterior half of the posterior limb and progressively shifted into the posterior half of the posterior limb in the more caudal horizontal sections. These observations resolve the current controversy about the exact anatomic location of the pyramidal tract in the posterior limb of the internal capsule. This controversy arose because previous authors failed to consider the changing rostrocaudal/anterior-posterior anatomy of the pyramidal tract as it courses through the posterior limb.

Musical Skill in Dementia: A Violinist Presumed to Have Alzheimer’s Disease Learns to Play a New Song

Previous studies have described patients with possible or probable Alzheimer’s disease (AD) who continued to play familiar songs skillfully, despite their dementias. There are no reports about patients with dementia who successfully learned to play new songs, and two papers describe failures of patients with AD to learn to play a new song although they continued to play familiar songs competently. In the present paper we describe a moderately demented patient (SL) with probable AD who learned to play a song (Cossackaya!) on the violin that was published after the apparent onset of his dementia. He showed modest retention of the song at delays of 0 and 10 minutes. This contrasts with his profound disturbance in both recall and recognition on other anterograde memory tests (word lists, stories, figures, environmental sounds, sounds of musical instruments), and marked impairment on measures of remote memory (famous faces, autobiographical memory). SL showed milder deficits in confrontation naming, verbal fluency and attention, but no dyspraxia or aphasic comprehension deficits. Except for the Block Design test, his visuospatial skills were intact. SL’s learning of the new song in the absence of any evidence of episodic memory is reminiscent of patients with temporal lobe amnesia who show better memory for song melody than for lyrics or verse, although his retention was not as good.

Left medial parietal lobe and receptive language functions Mixed transcortical aphasia after left antmior cerebral artery infarction

Three aphasic patients with infarctions involving the left anterior cerebral artery have been studied. Two had transcortical motor aphasia, and one had mixed transcortical (or isolation) aphasia. Based on computerized tomography in two patients and whole-brain sections in one, the patient with mixed transcortical aphasia had a lesion that went beyond the rolandic fissure to involve the anterior precuneus lobule of the left medial parietal lobe. In the patients with transcortical motor aphasia, the lesion was confined to the frontal lobe. From these cases and other data, it seems likely that the left medial parietal lobe has receptive language functions analogous to the motor language functions of the left medial frontal lobe, thus accounting for the mixed transcortical aphasia observed in the patient whose left anterior cerebral artery infarction involved both the medial parietal and medial frontal lobes.

Cerebral Localization of Functions and the Neurology of Language: Fact versus Fiction or Is It Something Else?:

Over the last 15 years there has been a burgeoning number of publications using functional brain imaging (>40,000 articles based on an ISI/Web of Science search) to localize behavioral and cognitive processes to specific areas in the human brain that are often not confirmed by traditional, lesion-based studies. Thus, there is a need to reassess what cerebral localization of functions is and is not. Otherwise, there is no rational way to interpret the escalating claims of localization in the functional imaging literature that is taking on the appearance of neurophysiologic “phrenology”. This article will present arguments to suggest that functional localization in the brain is a robust but very dynamic, four-dimensional process. It is a learned phenomenon driven over time by large-scale, spatially distributed, neural networks seeking to efficiently maximize the processing, storage, and manipulation of information for cognitive and behavioral operations. Because of historical considerations and space limitations, the main focus will be on localization of language-related functions whose theoretical neurological basis can be generalized for any complex cognitive-behavioral function.

Comprehension of affective prosody in multiple sclerosis

Deficits in cognition have been repeatedly documented in patients with multiple sclerosis (MS), but their ability to comprehend emotional information has received little study. Forty-seven patients with MS and 19 demographic controls received the comprehension portion of the A prosodia Battery, which is known to be sensitive to the impairments of patients with strokes and other neurological conditions. Patients also received tests of hearing, verbal comprehension and naming, a short cognitive battery, and the Beck Depression Inventory. Patients with MS were impaired in identifying emotional states from prosodic cues. The magnitude of the deficits was greatest for patients with severe physical disability and under test conditions of limited prosodic information. Correlational analyses suggested that the patients’ difficulties in comprehending affective prosodic information were not secondary to hearing loss, aphasic deficits, cognitive impairment, or depression. For some patients with MS, deficits in comprehending emotional information may contribute to their difficulties in maintaining effective social interactions.

Human Facial Expressions Are Organized Functionally Across the Upper-Lower Facial Axis

Most clinical research has focused on intensity differences of facial expressions between the right and left hemiface to explore lateralization of emotions in the brain. Observations by social psychologists, however, suggest that control of facial expression is organized predominantly across the upper-lower facial axis because of the phenomena of facial blends: simultaneous display of different emotions on the upper and lower face. Facial blends are related to social emotions and development of display rules that allow individuals to sculpt facial expressions for social and manipulative purposes. We have demonstrated that facial blends of emotion are more easily and accurately posed on the upper-lower than right-left hemiface, and that upper facial emotions are processed preferentially by the right hemisphere whereas lower facial emotions are processed preferentially by the left hemisphere. Based on these results, recent anatomical studies showing separate cortical areas for motor control of upper and lower face and the neurology of posed and spontaneous expressions of emotion, a functional-anatomic model of how the forebrain modulates facial expressions, is presented. The unique human ability to produce facial blends of emotion is, most likely, an adaptive modification linked to the evolution of speech and language. NEUROSCIENTIST 13(5):433—446, 2007.

fMRI evidence for the effect of verbal complexity on lateralisation of the neural response associated with decoding prosodic emotion

The pattern of intonation accompanying an utterance provides a powerful cue as to a speakers emotional state of mind. Most prior lesion studies have demonstrated that the nodal point for decoding these prosodic emotion cues is mediated by unimodal auditory cortex in the right posterior lateral temporal lobe. However, functional neuroimaging has brought with it increasing attention to the equivalent left hemisphere region in this role. This study used fMRI to quantitatively assess the hypothesis that involvement of the left posterior lateral temporal lobe depended on the linguistic load or verbal complexity of the prosodic emotion stimuli. BOLD contrast data was acquired on a 3T scanner whilst 16 healthy young adults identified the prosodic emotion in three conditions: sentences comprised of words, a repeated monosyllable, and a single prolonged syllable (asyllabic). Whole-brain analyses were performed using SPM5 and supplemented by posterior lateral temporal lobe region of interest (ROI) analyses. The whole-brain analyses appeared to show bilateral temporal lobe activation across the conditions, however, the ROI analyses indicated a highly significant decrease in activity in the left ROI as verbal complexity decreased. Changes in right ROI activity were not statistically significant. Our results indicate that the likelihood of observing a notable left temporal lobe response in functional neuroimaging studies of emotional prosody comprehension depends on the verbal complexity of the prosodic emotion stimuli. Despite the right hemisphere dominance underlying this task, the left hemisphere region may be co-activated in its attempt to extract phonetic-segmental information from the acoustic stimuli whether or not the stimuli contain meaningful phonetic-segmental information.

Relationship of leukoaraiosis to cognitive decline and cognitive aging

Objective:Leukoaraiosis (LA) is a common finding on MRI scans of the elderly. However, its exact relationship to cognitive decline and dementia is in dispute. Because LA involves the paracallosal white matter, we sought to determine if LA, uncomplicated by ischemic lesions or complaints of cognitive impairment, is associated with cognitive loss or difficulties with interhemispheric integration of behavioral functions. Methods:Two hundred fifty-seven MRI scans with deep white matter changes were screened. After a chart review, 38 patients had uncomplicated LA, and 31 gave informed consent to undergo cognitive and behavioral testing. Results:LA severity was not related to any of the cognitive or behavioral assessments. However, some dependent measures showed medium effect sizes that were in keeping with published findings, indicating that LA has a marginal impact on cognition. In comparison, robust relationships with age were found for certain tasks, suggesting that our cohort size was sufficient to detect meaningful clinical relationships. Conclusion:Based on statistical interpretations using effect sizes, LA severity may be better viewed as a biomarker for physiological brain aging that is in advance of chronological age, leaving the elderly individual at greater risk for developing dementia.

Psychological or physiological. Why are tetraplegic patients content

Objective: To assess the effects of spinal cord injury (SCI) on perceived health-related quality of life (QOL). Background: SCI is physically disabling, socially handicapping, and romantically limiting. Nevertheless, little is known about post-SCI neurocognitive and psychosocial life. Better understanding of the cognitive and emotional worlds of SCI patients is essential to better address and meet their needs and expectations. Methods: Twenty subjects with high-cord (T6 and above) complete (American Spinal Injury Association [ASIA] A) SCI (High SCI) were compared with 10 subjects with low-cord (T7 and below) ASIA A SCI (Low SCI) and with 11 Able-Bodied control subjects. Satisfaction with Life and Short Form-36 instruments were used to assess physical and emotional aspects of QOL. Analyses of variance were used to assess potential differences across groups. Results: Overall, satisfaction with life was the same among the groups. Expectedly, High SCI and Low SCI subjects reported lower physical functioning than Able-Bodied subjects (p < 0.0001). But, oddly, there were no differences in perceived physical role, physical health, or social functioning. Furthermore, High SCI subjects reported better perceived mental health than Able-Bodied control subjects (p = 0.004) and a trend over Low SCI subjects (p = 0.06), better perceived emotional role in society (p = 0.02), and greater vitality (p = 0.01) than Low SCI subjects and Able-Bodied subjects. Conclusions: Despite severe physical impairment and disability and frequent medical complications, subjects with complete spinal cord injury at high anatomic levels report better than average quality of life, being overall content. Reasons for these findings are unclear. Psychological adaptive reactions are likely, but the possible role of physiologic and neurocognitive changes needs further exploration.