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PubMedDate not supplied

Can music alleviate cognitive dysfunction in schizophrenia?

It has recently been reported that students performed relatively better on cognitive tasks after listening to music. Conceivably, music might reduce the level of arousal in subjects who are tense, thereby improving their performance. A test case would be schizophrenic subjects, noted for poor performance on tasks demanding attention, who have been characterized as suffering from hyperarousal, which mediates these attentional deficits. We investigated whether cognitive task performance could be facilitated by music in schizophrenics and report a beneficial effect.

Adult↗

PubMedDate not supplied

Behavioral response demands, cardiovascular reactivity, and essential hypertension.

Psychophysiologic reactions to behavioral challenges were examined in men aged 55 or less with no prior history of cardiovascular disorder. Three age-matched groups of twelve were recruited through factory screening: mild hypertensives (blood pressure in the range 175/105-145/90 persisting on retest), transient hypertensives (blood pressure above criterion on screening, falling on retest), and normotensives. Clinical examination, a laboratory rest session and period of blood pressure self-monitoring were followed by a laboratory stress session. The latter involved performance of two tasks demanding active behavioral coping (the Stroop interference task and video game) and one passive condition (a distressing movie). Mild hypertensives showed significantly greater pressor reactions (both in absolute and percentage terms) than normotensives to tasks requiring active behavioral coping, but not to the passive condition. The transient hypertension group produced heightened reactions in diastolic but not systolic pressure. Greater heart rate and pulse transit time reactions were also observed in the transient group, suggesting that exaggerated cardiac responsiveness to active challenges may be characteristic of the prehypertensive profile. No differences were recorded in electrodermal or respiratory variables, or in self-reported tension. Exaggerated pressor responses were also associated with high scores on the Hostility and Direction of Hostility questionnaire, and an absence of coronary-prone behavior. Implications for the etiology of essential hypertension are considered.

Anger↗

PubMed1998

Age-related deficits on the radial maze and in fear conditioning: hippocampal processing and consolidation.

Young adult, middle-aged, and old male F-344 rats were assessed for their hippocampal ability. This was accomplished by examining the animals on two different paradigms, each incorporating a simultaneous measure of hippocampal-dependent and -independent processing. The animals were fear conditioned and then tested for retention of the conditioning context and tone. This was followed by an 8-arm radial maze task which combined spatial working and cued reference memory elements. The two paradigms are compared in terms of task demands, potential confounds, and validity for aging studies. The results indicate that the performance of the animals on the two tasks is correlated. Age-related deficits limited to the hippocampal aspects of the above tasks were found, with no deficits found in the analogous but hippocampus-independent aspects of these tasks. The function of the hippocampus in incorporating new memories is time-related. Therefore, the possibility of age-related changes in consolidation was examined. It has previously been shown on the fear conditioning paradigm that the hippocampus is involved in retention of the aversive context for approximately 28 days. In the present study, an attempt was made to test the animals for retention of the conditioning context both early into the period of consolidation (10 days) and after consolidation should have been completed (52 days). The results indicate that, initially, the old animals show comparable retention to young rats. When examined later, young animals showed a stronger retention of the conditioning context than they had previously. The aged rats, however, did not seem to benefit from this additional period of time and in fact showed a decrease in retention of the conditioning context. The data are interpreted in terms of consolidation, alternative explanations of the data are presented, and suggestions are given for future research. Finally, the implications of such age-related changes in hippocampal consolidation on learning and memory are discussed.

Aging↗

PubMedDate not supplied

Age and experience-dependent representational reorganization during spatial learning.

Previously, we found that aged rats showed a significant enhancement of hippocampal CA1 place cell spatial specificity, as well as a reduction of hilar place cell spatial specificity, during asymptote performance of a spatial memory task. Because such an age effect was not observed when animals performed a nonspatial task, the present study tested the hypothesis that the different patterns of spatial selectivity observed in memory and nonmemory tests reflected a redistribution of spatial representations that occurred in response to changing task demands. In the present experiment, after animals became familiar with the test environment and motor demands of performance on a radial maze, CA1 and hilar place cells were recorded as they learned a spatial memory task. CA1 place cells recorded from unimpaired old, but not impaired old or young, animals became more spatially selective as animals learned the task. Hilar spatial selectivity for both age groups was not significantly related to choice accuracy. These data support the hypothesis that at least a subpopulation of aged rats may benefit from reorganization of spatial representations in such a way that the normal age-related spatial learning deficit is attenuated.

Aging↗

PubMed1997

Brain activation during an auditory 'oddball task' in schizophrenia measured by single photon emission tomography.

BACKGROUND: The study examines the effect of an auditory discrimination task on regional brain perfusion in schizophrenic patients. METHODS: Twenty patients were examined with single photon emission tomography (SPET), both resting and performing an auditory two-tone 'oddball' discrimination task. Statistical parametric mapping (SPM'95) was used to identify local activation effects and correlations between event related potential measures and regional perfusion. RESULTS: Compared with rest, patients activated left superior temporal gyrus during the task, together with right caudate. There was a (negative) correlation between P300-amplitude and perfusion during the activation procedure in both caudate nuclei and in the left lingual gyrus. No correlations were observed with P300-latency. Compared with healthy volunteers examined in earlier studies, our patients showed no frontal activation. This might be due to slightly different task demands in this study, but more likely to activation-hypofrontality in schizophrenic patients compared with controls. CONCLUSION: Auditory discrimination tasks can be used in schizophrenic patients to control their 'mental set' during brain perfusion studies with SPET. This approach can yield information about specific brain mechanisms associated with such tasks, and may make comparison with healthy volunteers easier.

Adult↗

PubMed2000

On the functions of double eyes in midwater animals.

Midwater predators often have double eyes consisting of a large upward-pointing part with a narrow field of view and high resolution, and a small downward-pointing part with a wide field of view and low resolution. In crustaceans with compound eyes the different eye parts are of basically similar construction, but in fishes the downward-pointing regions may employ unusual optical systems with unknown image-forming capabilities. It has been suggested that the upward-directed parts are used to detect silhouettes of animals against the residual daylight, whereas the lower parts look out for luminescent organisms. Here I calculate the sizes that apposition compound eyes would need to attain in order to fulfil these tasks, and the way that size should vary with depth. It is concluded that silhouette detection is much the more demanding task, and becomes increasingly difficult as light levels decrease. For this reason the upward-pointing parts must increase rapidly with depth. This is not the case with luminescence detectors, where the task is most difficult near the surface because of upwelling background light, and becomes easier with depth. On the whole these predictions fit well with the sizes and shapes of real midwater eyes, especially in the case of the hyperiid amphipods.

Animals↗

PubMed1975

Diurnal variation in logical reasoning.

Subjects performed two tests of logical reasoning at each of six different times of day. In terms of speed, preformance on both tests was found to improve markedly from 08.00 to 14.00 and then to fall off fairly rapidly. Accuracy was found to decrease fairly linearly over the day. The results are interpreted as indicating that the different functions relating performance efficiency to time of day found by previous workers are due to differences in task demands rather than to individual differences. It is suggested that the larger the short-term memory component of a task the earlier in the day performance peaks.

Achievement↗

PubMed2006

Imaging response inhibition in a stop-signal task: neural correlates independent of signal monitoring and post-response processing.

Execution of higher cortical functions requires inhibitory control to restrain habitual responses and meet changing task demands. We used functional magnetic resonance imaging to show the neural correlates of response inhibition during a stop-signal task. The task has a frequent "go" stimulus to set up a pre-potent response tendency and a less frequent "stop" signal for subjects to withhold their response. We contrasted brain activation between successful and failed inhibition for individual subjects and compared groups of subjects with short and long stop-signal reaction times. The two groups of subjects did not differ in their inhibition failure rates or the extent of signal monitoring, error monitoring, or task-associated frustration ratings. The results showed that short stop-signal reaction time or more efficient response inhibition was associated with greater activation in the superior medial and precentral frontal cortices. Moreover, activation of these inhibitory motor areas correlated negatively with stop-signal reaction time. These brain regions may represent the neural substrata of response inhibition independent of other cognitive and affective functions.

Adult↗

PubMed1993

Incidental and intentional recall in Parkinson's disease: an account based on diminished attentional resources.

The recall of common objects and their spatial location was examined in 65 patients with Parkinson's disease (PD) under conditions in which available attentional resources were manipulated by secondary task demands. PD patients were impaired at item recall particularly under intentional learning conditions but were unimpaired at recall of spatial location. These findings were similar in newly diagnosed, untreated cases as well as patients who had suffered with the disease for an average of 9.6 years. Test performance was not improved by levodopa therapy, despite it benefiting motor control, and was not impaired by anticholinergic medication. Item recall correlated significantly with other memory measures (particularly tasks of working memory) but only weakly with indices of physical disability and traditional frontal-lobe measures. Spatial recall, by contrast, correlated with memory quotient but no other cognitive measure and depression and disease duration failed to correlate significantly with performance on either recall task. These results are attributed to a deficit in attentional resources in PD that impairs performance most markedly for tasks and conditions that make the greatest demands upon effort.

Adult↗

PubMed1999

Neurophysiological correlates of the recognition of facial expressions of emotion as revealed by magnetoencephalography.

MEG correlates of the recognition of facial expressions of emotion were studied in four healthy volunteers. Subjects performed a facial emotion recognition task and a control task involving recognition of complex objects including faces. Facial emotion recognition activated inferior frontal cortex, amygdala and different parts of temporal cortex in a relatively consistent time sequence. The characteristics of these activations were clearly different from those recorded during the control task. Most interesting was the fact that faces evoked different MEG responses as a function of task demands, i.e., the activations recorded during facial emotion recognition were different from those recorded during simple face recognition in the control task. These findings support the assumption that MEG is able to specifically identify the activation pattern of the brain when recognition of the emotional expression of a face is performed.

Adult↗

PubMed2003

A biomechanical analysis of loads on x-ray technologists: a field study.

The aim of the study was to determine the biomechanical loads on radiographers in their occupation. Seven x-ray technologists (one male and six females with combined mean age 32.5 years, mean height 164.6 cm and mean weight 68.3 kg) volunteered to be videotaped while doing their jobs (same as normal and others in a simulated manner). X-ray technologists perform all these tasks regularly every day as part of their assignments. The magnitude of the load handled was measured on weighing scale and recorded. The videotape was played back in the laboratory and the initial and final frames of the tasks investigated were frozen for analysis. The joint angles, the height and weight of the technologist, and the load on their hands (weighed before the task was performed) were input into the 3-D Michigan static strength model for calculation of the lumbosacral load and loads on the joints of the extremities. The lumbosacral compression and shear loads were calculated for 16 tasks commonly performed by all x-ray technologists. The x-ray technologists' work was found to be biomechanically quite demanding. Tasks such as repositioning patients horizontally and lifting a patient from a wheelchair caused lumbosacral compression loads of 7,936N and 8,335N respectively, in which exceeded the maximum permissible limit set by NIOSH in 1981. The action limit defined by NIOSH was exceeded by other tasks. It is also of interest that the majority of the x-ray technologists were female.

Adult↗

PubMed2006

Sequential tapping interferes selectively with multiple-object tracking: do finger-tapping and tracking share a common resource?

Multiple-object tracking involves simultaneously monitoring positions of a number of target items as they move among distractors. Young adults are capable of tracking only 3-5 items at once. In this study we investigated the origin of this limitation by looking for secondary tasks that interfere with tracking. We compared tracking performance (baseline condition), with performance when participants tapped three fingers in a specific order while tracking (sequential tapping) or articulated three syllables in a specific order while tracking (sequential articulation). The articulation task was used to ensure that the interference produced by sequential tapping was more than would be expected by the executive demands of carrying out any two "attention-demanding" tasks at once. Even though sequential tapping does not require vision or memorizing the positions of external items, it produced significantly more interference than did sequential articulation, as might be expected if tracking and sequential tapping shared a common (limited) resource.

Adult↗

PubMed2003

Effects of attentional load on auditory scene analysis.

The effects of attention on the neural processes underlying auditory scene analysis were investigated through the manipulation of auditory task load. Participants were asked to focus their attention on tuned and mistuned stimuli presented to one ear and to ignore similar stimuli presented to the other ear. For both tuned and mistuned sounds, long (standard) and shorter (deviant) duration stimuli were presented in both ears. Auditory task load was manipulated by varying task instructions. In the easier condition, participants were asked to press a button for deviant sounds (target) at the attended location, irrespective of tuning. In the harder condition, participants were further asked to identify whether the targets were tuned or mistuned. Participants were faster in detecting targets defined by duration only than by both duration and tuning. At the unattended location, deviant stimuli generated a mismatch negativity wave at frontocentral sites whose amplitude decreased with increasing task demand. In comparison, standard mistuned stimuli generated an object-related negativity at central sites whose amplitude was not affected by task difficulty. These results show that the processing of sound sequences is differentially affected by attentional load than is the processing of sounds that occur simultaneously (i.e., sequential vs. simultaneous grouping processes), and that they each recruit distinct neural networks.

Acoustic Stimulation↗

PubMed2004

An fMRI investigation of speech and tone segmentation.

Recent research strongly indicates that phonological tasks activate a subregion of the inferior frontal gyrus. The purpose of the present fMRI study was to investigate the extent to which activation of this region during phonological processing is due to speech processes per se such as articulatory recoding or to other cognitive task demands such as working memory. Thus, we compared activation patterns during segmentation of speech and tone sequences to a tone discrimination task. In particular, participants performed same/different judgments on pairs of words, pseudowords, and tone sequences that required segmentation of a continuous acoustic signal as well as tone pairs that did not require segmentation. Accuracy and reaction time data showed that speech and tone sequence segmentation conditions patterned more similarly to each other than to tone discrimination pairs. Analyses of group data revealed strong activation of the region at the border of the left inferior and middle frontal gyrus for all three segmentation conditions compared to tone discrimination, but no consistent differences were observed when word and pseudoword segmentation were directly contrasted. Analyses of individual subjects indicated that a large number of participants activated a small area of the middle frontal gyrus during the speech conditions compared to the sequences. These results suggest that a significant portion of active frontal areas is recruited for extracting acoustic information and maintaining it in memory for decision. However, some regions at the border of the inferior/middle frontal gyrus may be unique to speech segmentation.

Adult↗

PubMed1985

Alcohol, selective attention and sexual arousal in men.

Thirty-two men social drinkers were randomly assigned to the cells of a balanced placebo design to investigate the effects of expected and actual alcohol consumption on sexual responsiveness. Using a dichotic listening task, erotic and nonerotic information was presented in the nonattended channel while subjects performed simple (low-attention demand) and complex (high-attention demand) numerical tasks presented in the attended channel. Penile tumescence was recorded continuously in response to all audiotaped information. The high-attention demand task significantly interfered with sexual arousal compared with the low-attention demand task, primarily because of the significant suppressant effect of alcohol on arousal during the complex task. The lack of differences in tumescence under the two cognitive tasks when subjects were sober is inconsistent with the cognitive interference model of sexual arousal. Alcohol expectations increased arousal during the low-attention demand task, whereas actual alcohol consumption decreased arousal only during the high-attention demand task. Both effects are attributed to the different effects of these separate variables on attentional processes. The clinical implications are discussed.

Adolescent↗

PubMed1996

Classification deficits in Alzheimer's disease with special reference to living and nonliving things.

The present study was conducted to assess the hypothesis that visual similarity between exemplars within a semantic category may affect differentially the recognition process of living and nonliving things, according to task demands, in patients with semantic memory disorders. Thirty-nine Alzheimer's patients and 39 normal elderly subjects were presented with a task in which they had to classify pictures and words, depicting either living or nonliving things, at two levels of classification: subordinate (e.g., mammals versus birds or tools versus vehicles) and attribute (e.g., wild versus domestic animals or fast versus slow vehicles). Contrary to previous results (Montañes, Goldblum, & Boller, 1995) in a naming task, but as expected, living things were better classified than nonliving ones by both controls and patients. As expected, classifications at the subordinate level also gave rise to better performance than classifications at the attribute level. Although (and somewhat unexpectedly) no advantage of picture over word classification emerged, some effects consistent with the hypothesis that visual similarity affects picture classification emerged, in particular within a subgroup of patients with predominant verbal deficits and the most severe semantic memory disorders. This subgroup obtained a better score on classification of pictures than of words depicting living items (that share many visual features) when classification is at the subordinate level (for which visual similarity is a reliable clue to classification), but met with major difficulties when classifying those pictures at the attribute level (for which shared visual features are not reliable clues to classification). These results emphasize the fact that some "normal" effects specific to items in living and nonliving categories have to be considered among the factors causing selective category-specific deficits in patients, as well as their relevance in achieving tasks which require either differentiation between competing exemplars in the same semantic category (naming) or detection of resemblance between those exemplars (categorization).

Aged↗

PubMed2004

Cognitive changes in short-term hypothyroidism assessed with event-related brain potentials.

Hypothyroidism is a common clinical problem during (131)Iodine-therapy of thyroid cancer. In the present investigation, possible cognitive dysfunction during hypothyroid state was assessed by means of neuropsychological tests and the recording of event-related brain potentials (ERPs). Fifteen patients undergoing therapy for thyroid cancer were examined twice: (1) substituted with thyroid hormones, (2) during hypothyroid state immediately prior to treatment. Standard neuropsychological tests were applied during both sessions and subjects showed a mild-to-moderate impairment in their hypothyroid state. In addition, ERPs were recorded from 19 scalp sites while subjects performed two visual search tasks. The serial task required the effortful one-by-one scanning of several items within a visual array, while the parallel task allowed processing of all stimulus items in parallel and automatically. ERPs showed a marked amplitude decrement and delay of the P3 component known to index the speed of stimulus evaluation and the amount of available processing resources. This effect was present only for the serial search task, while no changes were seen in the parallel search task. These data show that hypothyroidism during (131)Iodine-therapy is associated with clinically relevant cognitive dysfunctions, especially with effortful attention demanding tasks.

Acute Disease↗

PubMed1994

Comments on neuropsychological evaluation of epilepsy surgery: are the tests sensitive enough?

Epileptic lesions often affect two of the most important functions in human behavior, memory and emotion. While cognitive functions, e.g, speech and memory, are normally carefully studied, emotional and psychosocial aspects of behavior are often overlooked in the pre- and postoperative evaluation of epilepsy patients. In my comment, I will address the need for methodological and theoretical refinement, especially regarding measurements of emotional and psychosocial aspects. In evaluating memory functions, a functionalistic approach is suggested; that is, in contrast to the entity view, studies should focus on the interaction between task demands and the available cognitive capabilities of the rememberer. We should develop a broad set of tests and demonstrate dissociations between different tasks that tap different capabilities and different memory systems: we should look for patterns of results rather than single scores.

Brain↗