Cognitive intervention in unemployed individuals with reading and writing disabilities.

Sixty native-born Swedish unemployed participants with reading and writing disabilities (R&WD) participated in a 20-week educational program aimed at improving reading and writing, verbal memory, self-confidence, and flexibility of perspectives. They were tested with a comprehensive battery (interviews, questionnaires, neuropsychological tests, and tests of academic achievement) before and after the intervention. Sixteen controls, matched for sex, age, education, and nonverbal IQ, participated in the pre- and posttest sessions but received only standard unemployment interventions. The educational program participants' performance in tests assessing spelling, decoding of letters, self-confidence, and flexibility improved significantly in comparison with the controls after the intervention. A significantly larger number of the participants had obtained work or started a regular education than expected. A substantial proportion of unemployed participants have R&WD and it appears that an intensive but fairly short educational program can improve their accessibility to the labor market and their motivation for study.

Dyslexia among Swedish prison inmates in relation to neuropsychology and personality.

Several investigations have reported high frequencies of reading and writing disabilities in criminal populations. The aims of the present study were to assess the frequency of dyslexia among Swedish prison inmates and to relate dyslexia to other indices of neuropsychological functions. Sixty-three prison inmates with Swedish as their native language, age 19 to 57 years, were examined by interviews, tests of academic achievement, and neuropsychological assessment. Twenty-six (41%) were diagnosed as dyslexic. As expected, the dyslexic group performed more poorly on verbal tests as compared to the normal readers among the prison inmates, but they also performed more poorly on tests measuring nonverbal abilities. The dyslexic group had higher frequencies of paranoid and avoidant personality disorders compared to the nondyslexics. They also reported higher levels of anxiety and suspicion and a lower degree of socialization. Previous studies report low IQ to be associated with criminal propensity, supporting the interpretation that a double handicap (dyslexia and low IQ) increases the risk of entering a criminal career and remaining in it.

Alcohol activates the cerebral reward system in man.

OBJECTIVE: We investigated the effect of 0.07% alcohol on regional brain activity at rest and during cognitive performance in order to elucidate the anatomical substrate for the effects of alcohol in man as well as to clarify the interaction between changes in cerebral activity induced by cognitive performance and alcohol inebriation. METHOD: Regional cerebral blood flow (3D-PET, 15O Butanol) was measured in 13 male, nonalcoholic volunteers. Each subject was scanned 12 times, three scans in each of the following four situations: sober/rest, sober/test and inebriated/rest, inebriated/test. We used statistical parametric mapping and a computerized brain atlas for localization. RESULTS: Alcohol induced a sense of inebriation and elation as well as a relative increase of the cerebral blood flow in medial parts of the temporal lobes, in the anterobasal parts of the anterior cingulate cortex including the septal region. In addition, there was an increase of blood flow in midline parts of the lower brain stem. Relative decreases of flow were observed in the cerebellum and in the occipital cortex bilaterally. In the sober state, a computerized perceptual maze test and a (silent) serial seven test induced two distinct neocortical activation patterns that were specific to the tasks. Alcohol did not change these patterns and the test performance was also uninfluenced. CONCLUSIONS: A moderate dose of alcohol selectively activates target structures that pertain to the so-called cerebral reward system and the ascending reticular activating system. Alcohol (approximately 0.07%) appears to have only minor effects in the neocortical systems that are involved in on-line cognitive activity. This apparent independence between the subcortical alcohol target and the neocortical cognitive mechanisms is a new finding that appears to be of importance for an understanding of the effect of moderate doses of alcohol on the brain.

History of brain imaging in psychiatry.

This is a brief history of the use of brain imaging in neuropsychology and psychiatry. There are two main parts. The first concerns brain imaging using regional cerebral blood flow (rCBF) measurements with xenon clearance. The 2-dimensional rCBF techniques have been used since 1961. The second concerns application of PET techniques starting in the early 80s. Brain imaging has yielded new information on consciousness, cortical localization, language, emotions and will. In psychiatry, brain imaging has revealed regional cerebral abnormalities in schizophrenia, affective disorders, DAMP, as well as following alcohol intake.

Silent speech activates prefrontal cortical regions asymmetrically, as well as speech-related areas in the dominant hemisphere.

Regional cerebral blood flow (rCBF) was measured simultaneously over the right and left hemispheres by 2 x 32 detectors in 30 healthy volunteers with a two-dimensional iv xenon-133 technique, during (1) rest and during (2) audible and (3) silent counting (101, 102,...). Mean hemisphere CBF increased significantly in both hemispheres during the activations. Audible speech activated rolandic and temporoparietal regions mainly on the right side. This pattern covers auditory and para-auditory as well as motor (tongue/larynx) regions. Most likely those regions are involved in auditory feedback and voice control. Silent speech (internal speech) gave a clearly different activation pattern involving (1) left-sided regions related to speech perception and speech motor control (including the SMA) and (2) a right dorsolateral prefrontal area that may be related to attention mechanisms. The silent speech pattern appears to demonstrate aspects of internal (cognitive) feedback activity in which prefrontal cortical regions are activated significantly. Audible and silent counting may represent two principally different types of cerebral feedback systems, one for overt sensory-motor activity and one for a pure internal cognitive feed-back.

The will of the brain: cerebral correlates of willful acts.

Current imaging techniques can depict physiological events in the brain which accompany sensory perception and motor activity, as well as cognition and speech. "Pure" mental events unaccompanied by sensory input or motor/behavioral output also induces cerebral functional changes which apparently are related to inner representations of thoughts, ideas, visions, inner speech and so forth. Cerebral events during cognition, mental effort, imagined volitional acts, augment the activity in the prefrontal cortex. An augmentation in the cerebellum is also recorded. It is known that temporally organized (sequential) neuronal activity takes place in these structures. The prefrontal activation accompanying volitional acts most likely corresponds to a willful mobilization of inner representations of future events. These representations serve as action programs for the achievement of the goal. Phylogenetically older parts of the cerebral cortex close to the midline (the cingulate gyrus) participate in willful acts. They are possibly involved in emotional/motivational ("value") aspects of volition. Abnormal volition ("sick will") is encountered in organic dementia, Parkinson's disease, depression, and schizophrenia. Such disorders are characterized by inactivity, lack of ambitions, and a reduced motor and verbal output. Patients in these groups often show a decreased activity in prefrontal regions. Individuals with supraorbital and mesial frontal lesions may develop a so-called psychopathic behavior including abnormalities of volition with lack of impulse control, boredom susceptibility, sensation-seeking behavior, and abnormal risk taking. Knowledge about cerebral events coupled to willful acts may shed some light on the "collective will" expressed by groups of individuals and organizations.

EEG topography of acute ethanol effects in resting and activated normals.

Acute effects of ethanol on spectral characteristics of the EEG were studied using 18 recording sites and topographic mapping. The EEG was recorded both at rest and during a mental arithmetic task. Healthy young male volunteers were randomly assigned to an ethanol (n = 22) or a placebo (n = 15) group. The ethanol group received a total dose of 1.0 g/kg, divided into two equal doses given 75 minutes apart. and measurement sessions took place at baseline and after each dose. The placebo group underwent a similar schedule. Power in the theta, alpha and beta bands all increased in the ethanol group, but only the theta and beta bands clearly separated ethanol from placebo. Alpha increases were seen in the placebo group as well. The ethanol-induced changes were greater in the left hemisphere than in the right, having the effect of attenuating the right-over-left asymmetry seen at baseline. Differences between ethanol and placebo were more marked in the mentally activated condition, since the changes seen at rest were inhibited by the activation in the placebo group, but not in the ethanol group. The results indicate (1) that ethanol induces a less differentiated pattern of activity within the brain at rest, and (2) that it impairs the capacity to activate the brain under the challenge of a mental task.

Ethanol reduces asymmetry of visual rCBF responses.

Visual regional CBF (rCBF) responses were measured in 10 healthy male subjects before and after an ethanol dose of 1 g/kg body weight. This dose induces well-established cerebral vasodilatation. However, significant bilateral occipital increases were found in both conditions. Apparently, the coupling between neuronal activity and rCBF is preserved following ethanol. The occipital and posterior parietal flow increases were, however, larger on the right than the left side in the sober state. During inebriation the asymmetry disappeared, possibly representing a more undifferentiated processing of visual information. We propose that ethanol causes a reduced inhibition of the left posterior cortex and a reduction of right-hemisphere information processing.

Acute effects of alcohol on regional cerebral blood flow in man.

Acute effects of alcohol in a low (0.7 g/kg) and a high dose (1.5 g/kg) on regional cerebral blood flow (rCBF) were measured with 133Xe inhalation technique at resting conditions in 13 normals. Mean hemisphere CBF increased globally by 12% at the lower dose and 16% at the higher dose. A normal hyperfrontal flow pattern was seen in both alcohol conditions. There were, however, significant regional differences in response to alcohol. The largest rCBF increase was observed in prefrontal regions at the lower dose, and in temporal regions at the higher. Expressed in relative values (% of the whole brain CBF), the temporal rCBF increased linearly with increasing alcohol dosage, while the prefrontal rCBF showed a increase at the lower dose followed by a decrease at the higher dose. It is concluded that alcohol has two types of acute effects on rCBF, a global vasodilatory effect and some regional effects, most clearly seen in prefrontal and temporal regions. The prefrontal flow augmentation following acute alcohol intake may be related to a transient arousal reaction, which has been reported by others. The temporal flow increase may be related to effects of alcohol on emotions and mood.

Motor imagery activates the cerebellum regionally. A SPECT rCBF study with 99mTc-HMPAO.

Our earlier findings of a cerebellar activation during motor imagery (Brain Res., 535 (1990) 313-317) were made with a technique with low regional resolution. Therefore we could not elucidate the distribution of the cerebellar activation. In the present study the cerebellar regional cerebral blood flow (rCBF) changes during motor imagery (MI) was measured with a single photon emission computed tomography (SPECT) rCBF method (99mTc-HMPAO) with higher regional resolution during (1) silent counting, and (2) MI (which included silent counting) in 17 normal subjects. Comparing the SPECT results from the two tasks revealed the regional activations during MI. We confirmed that the most pronounced regional activations during MI were found in the cerebellum, especially in its infero-lateral parts on both sides.

[Surveying the brain-psyche connection. The frontal lobes control cerebral and mental "timing"]. / Samband Hjärna-psyke kartläggs. Frontalloberna styr hjärnans och psykets "tidtabeller".

Regional variations in the brain related to various forms of mental activity can be mapped with rapid isotope methods. Normal resting consciousness entails a high level of activity in large parts of the central nervous system (CNS)--particularly in the frontal lobes. Here the level of activity is reduced during loss of consciousness, intoxication, coma, and also during sleep. Specific functional landscapes can be recorded during perception of sensory stimuli, production of voluntary movements and speech, and in connexion with problem solving, mental imagery, thinking, etc. Effects of emotional stimuli can also be traced. These findings support the idea that a prerequisite for mental activity is a serial activity in multiple distributed networks. In this review, emphasis is laid upon the serial nature (the temporal organisation) of both neurophysiological and mental events. Much new evidence suggests that the serial nature of brain activity and of the cognition is governed by the frontal lobes.

Quantified EEG and cortical evoked responses in patients with chronic traumatic frontal lesions.

Eighteen frontal trauma patients and 17 age-matched control subjects had quantified EEGs and measurements of sensory (SEP) and auditory evoked potentials (P300) using a Biologic Brain Atlas III system. The findings were compared to the conventional paper EEG, and to the frontal lesion volumes, severity of head injury, and outcome variables. The quantified EEG confirmed the pathological findings detected by visual inspection, but some regional abnormalities were more easily detected by topographic mapping. The regional distribution of pathological slowing corresponded well with the morphological lesions in most patients. The modal frequency of EEG correlated both with lesion volume and injury severity and with the outcome variables. There were no pathological findings in the SEPs, and all but one patient had clearly distinguishable P300 responses. There was a significant reduction in P300 amplitude in the frontal patients at the anterior, but not at the posterior electrodes. The topographical distribution of the P300 changes corresponded well with the morphological lesions. Our findings indicate that the P300 potential is, in part, dependent upon the prefrontal cortical areas. The present study thus supports P300 investigations which have shown amplitude reduction in other disorders (e.g., schizophrenia) with a presumed prefrontal dysfunction.

Aspects of stability of regional cerebral blood flow in chronic schizophrenia: an 18-year followup study.

Regional cerebral blood flow (rCBF) measurements and psychiatric ratings were performed on seven schizophrenic patients (mean age = 41.4 years) who had been examined 18 years previously in a study that used similar psychiatric ratings and a comparable rCBF technique. Neither the clinical symptomatology nor the rCBF level and distribution had changed appreciably between 1972 and 1990. The findings indicate that cerebral functional activity in chronic schizophrenia remains constant in spite of continuous neuroleptic medication.

Disturbances of speech prosody following right hemisphere infarcts.

The ability to perceive and express emotional, as well as number of linguistic prosodic qualities of speech was tested in 20 Swedish-speaking patients with right-sided cortical, as well as purely subcortical brain infarcts, and in 18 normal controls. The infarcts were assessed by clinical neurological examination, and by CT, EEG, and measurements of regional cerebral blood flow (rCBF). In the patients the identification of emotional messages was disturbed, as well as the identification and production of several linguistic prosodic qualities. The study supports the claim that prosodic impairment could be linguistic in nature, and not secondary to affective disorder. The total degree of anatomical and functional disturbance of the right hemisphere played a role for both the ability to identify emotional messages and for identification of two of the linguistic prosodic qualities tested. However, it was not possible to find support for the hypothesis that the organization of prosody in the right hemisphere mirrors that of propositional speech on the left side.

Volumes of chronic traumatic frontal brain lesions measured by MR imaging and CBF tomography.

The volumes (ml) of chronic traumatic frontal brain lesions were compared measured "morphologically" with MR imaging (T1 and T2 weighted images) and "functionally" with a tomographic rCBF technique (SPECT with 133Xe i.v.). The T1 volumes varied between 11 and 220 ml. The correlation between T1 and T2 volumes was 0.95, the T2 volumes being 33% larger than T1 volumes (p less than 0.001). The functional SPECT volumes were considerably larger (range 16-324 ml) than the MR volumes. The mean volume difference was 81% between T1 and SPECT images (p less than 0.001), and 35% between T2 and SPECT images (p less than 0.001). Correlations between the MR and SPECT volumes were also higher for T2 than T1 volumes. The volume difference is most likely explained by a functional decrease in regions around the lesion in which no morphologic change visible on MR images had taken place. MR and SPECT volume measurements were positively related to persistent lack of energy and personality changes, but only moderately related to duration of impaired consciousness and neuropsychologic outcome.

The cerebellum participates in mental activity: tomographic measurements of regional cerebral blood flow.

Measurements in man of regional cerebral blood flow (rCBF) have demonstrated a number of cortical and subcortical events coupled to sensory stimulation or motor performance. It has also been shown that local activity changes take place in the cortex during 'pure' mental activity such as motor imagery (unaccompanied by sensory input or motor output). Thus, our group has previously shown that imagination of hand movements gives predominantly a frontal cortical rCBF activation while the corresponding hand movement activates the rolandic hand area mainly. In this paper we report tomographic rCBF measurements with a 133-Xenon SPECT technique during imagined tennis movements and silent counting. Both procedures gave rise to a significant cerebellar activation in addition to cortical rCBF changes. Apparently, the cerebellum may participate in pure mental activity. It possibly plays a role for the temporal organization of neuronal events related to cognition.

Brain structures participating in mental simulation of motor behavior: a neuropsychological interpretation.

This paper reviews findings from cognitive and sport psychology, as well as from neurophysiology, concerning mental simulation of movement. A neuropsychological hypothesis is advanced to explain why mental practice can improve motor skill learning. Mental practice activates certain brain structures selectively as shown by measurements of regional cerebral blood flow. It appears likely that this activation improves the subsequent control of execution of movements. It is pointed out that the study of simulation of movements may not only be of value for sport training but also have importance for the rehabilitation of patients with motor disturbances following lesions of the central nervous system.

Do single right hemisphere infarcts or transient ischaemic attacks result in aprosody?

The ability to perceive and express prosodic qualities of speech was tested in 21 patients with a single focal ischaemic disturbance of the right hemisphere, 14 patients having an infarct and 7 transient ischaemic attacks, and in 21 age-matched normal controls. All patients were predominantly right-handed. None showed signs of aphasia. Pure tone audiometry showed acceptable hearing for speech. The cerebral lesions were assessed by clinical neurologic examination, and by CT, EEG and measurement of regional cerebral blood flow (rCBF) using intravenous 133-xenon. The prosodia test included items testing: the ability to perceive accentual and emotional qualities of speech, and the ability to express and vary such qualities. The test did not discriminate between the patients and the controls, although some patients had large right-sided lesions. This negative finding indicates that aprosody in patients with brain lesions appears more difficult to detect than has previously been assumed. Highly sensitive tests are most likely required.