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PubMed2006

[The evaluation of preoperative and postoperative frontal lobe functions in three operative cases of meningioma].

We report three cases of frontal meningioma with their pre- and post-operative evaluations of higher brain functions, especially of frontal lobe functions. All of the cases showed the improvement of the frontal lobe functions after the tumor removal. The evaluations of frontal lobe functions in benign brain tumors such as a meningioma are reported only in a few cases. The evaluations of frontal lobe functions in the operative cases of benign brain tumors provide many interesting and valuable informations about frontal lobe functions. So we must be more interest in evaluations in higher brain functions and accumulate cases for the further analysis of higher brain functions.

Female↗
PubMed1997

The evolution of the frontal lobes: a volumetric analysis based on three-dimensional reconstructions of magnetic resonance scans of human and ape brains.

Scenarios regarding the evolution of cognitive function in hominids depend largely on our understanding of the organization of the frontal lobes in extant humans and apes. The frontal lobe is involved in functions such as creative thinking, planning of future actions, decision making, artistic expression, aspects of emotional behavior, as well as working memory, language and motor control. It is often claimed that the frontal lobe is disproportionately larger in humans than in other species, but conflicting reports exist on this issue. The brain of the apes in particular remains largely unknown. In this report we measure the volume of the frontal lobe as a whole and of its main sectors (including cortex and immediately underlying white matter) in living humans, and in post-mortem brains of the chimpanzee, gorilla, orang-utan, gibbon and the macaque using three-dimensional reconstructions of magnetic resonance (MR) scans of the brain. On the basis of these data we suggest that although the absolute volume of the brain and the frontal lobe is largest in humans, the relative size of the frontal lobe is similar across hominoids, and that humans do not have a larger frontal lobe than expected from a primate brain of the human size. We also report that the relative size of the sectors of the frontal lobe (dorsal, mesial, orbital) is similar across the primate species studied. Our conclusions are preliminary, because the size of our sample, although larger than in previous studies, still remains small. With this caveat we conclude that the overall volume of the frontal lobe in hominids enlarged in absolute size along with the rest of the brain, but did not become relatively larger after the split of the human line from the ancestral African hominoid stock. Aspects other than relative volume of the frontal lobe have to be responsible for the cognitive specializations of the hominids.

Animals↗
PubMed2005

Total sleep deprivation and novelty processing: implications for frontal lobe functioning.

OBJECTIVE: Mounting evidence suggests that the frontal lobes are particularly vulnerable to total sleep deprivation (TSD). Detection of novelty involves the frontal lobes. The presentation of rare, novel stimuli elicits an event-related potential (novel P3), which maximizes over anterior regions of the scalp. We hypothesized that TSD would impair novelty detection, resulting in a smaller novel P3 over the frontal region, with a topographic shift toward posterior areas. METHODS: An auditory novelty oddball task was administered to a TSD group after 36 h of waking and again following recovery sleep, and to a control group after 12 h of waking. EEG was recorded from Fz, Cz and Pz. RESULTS: A large anterior P3 was elicited in the control group. In the TSD group, this novel P3 was smaller at Fz. A later novel positivity appeared in parietal areas. The novel P3 returned to baseline levels and the late novel P3 was difficult to observe following recovery sleep. CONCLUSIONS: TSD appears to compromise the usual automatic detection of novelty probably due to frontal deactivation. Participants may compensate by relying on posterior brain mechanisms involving active memory comparison. The late novel P3 component may also reflect a secondary effortful attempt to encode and to categorize novel stimuli. SIGNIFICANCE: This study suggests that TSD may compromise cognitive functioning in different regions of the brain. The detection of novelty, probably mediated by the frontal lobes, is particularly at risk.

Acoustic Stimulation↗
PubMed1994

Correlations of phosphomonoesters measured by phosphorus-31 magnetic resonance spectroscopy in the frontal lobes and negative symptoms in schizophrenia.

Frontal lobe dysfunction has been linked to negative symptoms of schizophrenia. We used phosphorus-31 magnetic resonance spectroscopy (31P-MRS) to examine phosphorous metabolism in frontal brain regions in 26 schizophrenic patients compared with 26 sex- and age-matched control subjects. The relative signal intensities of phosphorous metabolites in frontal regions did not differ significantly between schizophrenic patients and control subjects. However, phosphomonoester levels were significantly decreased in frontal regions of 12 schizophrenic patients who had high scores on negative symptom subscales from the Brief Psychiatric Rating Scale (i.e., emotional withdrawal, motor retardation, and blunted affect) compared with 14 patients with low negative symptom scores on the same subscales and control subjects. The correlations between negative symptoms and phosphorous metabolism in the frontal lobes support the "hypofrontality hypothesis" in schizophrenia.

Adenosine Triphosphate↗
PubMed1981

Direct and indirect pathways from the amygdala to the frontal lobe in rhesus monkeys.

To elucidate the anatomical relationships between the frontal association cortex and the limbic system in primates, projections from the amygdala to frontal cortex were studied in the rhesus monkey using retrograde and anterograde tracing methods. Following injections of horseradish peroxidase (HRP) into the orbital prefrontal cortex, the gyrus rectus, the superior frontal gyrus, and the anterior cingulate gyrus of the frontal lobe, labeled neurons were found in the basolateral, basomedial, or basal accessory nuclei of the amygdala. None of these nuclei contained labeled neurons following HRP injections into the principal sulcus or the lateral inferior convexity of the frontal lobe. This selective distribution of amygdala connections was confirmed by injection tritiated amino acids into the amygdala. Silver grains were present only over the orbital cortex and gyrus rectus on the ventral surface of the frontal lobe and over the superior prefrontal gyrus and anterior cingulate gyrus on the medial wall of the hemisphere, while the dorsolateral prefrontal cortex was free of radioactivity. The isotope injection of the amygdala also revealed a projection to the magnocellular moiety of the mediodorsal nucleus (MDmc) which is known to innervate the same ventromedial regions of the frontal lobe that receive direct connections from the amygdala. Although MDmc and amygdala project to the same cortical regions, their terminal fields are different. The direct amygdala input terminates in layer 1 in orbital cortex and gyrus rectus and layer 2 in the dorsomedial cortex and cingulate gyrus, while the thalamic input is primarily to layer 3 and, in some areas, also the superficial half of layer 1. These findings indicate that the frontal lobe of rhesus monkeys can be subdivided into two separable cortical regions: 1) A ventromedial region including the anterior cingulate gyrus which receives both direct (amygdalo-cortical) and indirect (amygdalo-thalamo-cortical) input from the amygdala; and 2) a dorsolateral frontal region which is essentially devoid of either direct or indirect amygdalofugal axons. On the basis of its selective relationship with the amygdala, the ventromedial region may be considered the "limbic" portion of the frontal association cortex.

Amygdala↗
PubMed2001

Thalamic asymmetry on interictal SPECT in patients with frontal lobe epilepsy.

BACKGROUND: Interictal brain single photon emission computed tomography (SPECT) is useful for the detection of seizure focus. Recent reports indicate a hypoperfusion in the ipsilateral thalamus as a seizure focus on interictal SPECT in temporal lobe epilepsy. In frontal lobe epilepsy (FLE), however, the alteration of perfusion in the thalamus has not been well documented. This study aimed to assess whether perfusion analysis on the thalamus may add useful information for the detection of epileptic foci in patients with FLE. METHODS: Interictal brain SPECT was performed in 11 patients with FLE. The asymmetry index for the thalamus and frontal area in the SPECT image was calculated in order to compare the laterality of the seizure foci. RESULTS: Thalamic asymmetry was seen in seven patients (64%), while cortial asymmetry was seen in six patients (55%). The concordance with the lateralization of the seizure foci was 6/7 (86%) in the thalamus, and 4/6 (67%) in the frontal area. Four patients showed only thalamic asymmetry. Concordance with the lateralization of the seizure focus was found in all of them. CONCLUSION: These preliminary results suggest that hypoperfusion in the thalamus may have a complementary role to lateralize the epileptic foci in patients with FLE.

Adolescent↗
PubMed2004

Lateralization of the frontal lobe functions elicited by a cognitive bias task is a fundamental process. Lesion study.

Cognitive neuroscience researchers have hypothesized that context-dependent and context-independent response selection is associated with the left and right frontal lobe, respectively, in right-handed adult males. Patients with left frontal lobe lesions show context-independent reasoning in a cognitive bias task (CBT), while those with right frontal lesions show context-dependent reasoning. Young children show more context-independent responses in a modified CBT (mCBT), while adolescents and adults show more context-dependent responses. We investigated the cognitive bias of right-handed children with unilateral frontal lobe lesions/epileptic foci to explore the plasticity of lateralization in the frontal lobes. The study included eight children with left frontal lobe lesions/epileptic foci (LLF) and four children with right frontal lobe lesions/epileptic foci (RLF). Twenty-three right-handed age-matched males served as controls. A computer presented version of the original card-choice task that was simplified and modified for children was used (mCBT). Simple visual stimuli differed dichotomously in shape, color, number, and shading. A target object presented alone was followed by two choices from which subjects made selection based on preference. Considering all four characteristics, the degree of similarity between the target and the subjects' choice was scored for 30 trials. A high score indicated a context-dependent response selection bias and a low score indicated a context-independent bias. The RLF subjects had a higher converted score (mean: 26.8+/-2.2), while LLF subjects showed a lower converted score (mean: 7.75+/-6.3). There were highly significant differences between LLF subjects and the other groups (P<0.001 vs. controls or RLF subjects). No significant correlations were observed between the converted scores and the age at onset, time since insult, or IQ in either LLF or RLF subjects. These findings suggest that the lateralization of frontal lobe function elicited by mCBT is fundamental and independent of language lateralization, rather than secondary to it. Furthermore, these findings also indicate that the timetable for the development of lateralized frontal lobe functions depends upon biologic factors.

Adolescent↗
PubMed2001

Neuropsychiatry of frontal lobe dysfunction in violent and criminal behaviour: a critical review.

OBJECTIVES: To establish the link between frontal lobe dysfunction and violent and criminal behaviour, based on a review of relevant literature. METHODS: Articles relating evidence of frontal lobe dysfunction with violence or crime were collected through a MEDLINE search using the keyword "frontal lobe" combined with the terms "aggression," "violence," "crime," "antisocial personality disorder," "psychopathy," "impulse control disorders", and "episodic dyscontrol." Reference lists were then searched for additional articles. RESULTS: High rates of neuropsychiatric abnormalities reported in persons with violent and criminal behaviour suggest an association between aggressive dyscontrol and brain injury, especially involving the frontal lobes. The studies reviewed support an association between frontal lobe dysfunction and increased aggressive and antisocial behaviour. Focal orbitofrontal injury is specifically associated with increased aggression. Deficits in frontal executive function may increase the likelihood of future aggression, but no study has reliably demonstrated a characteristic pattern of frontal network dysfunction predictive of violent crime. CONCLUSIONS: Clinically significant focal frontal lobe dysfunction is associated with aggressive dyscontrol, but the increased risk of violence seems less than is widely presumed. Evidence is strongest for an association between focal prefrontal damage and an impulsive subtype of aggressive behaviour.

Aggression↗
PubMed1989

Frontal-lobe dysfunction and antisocial behavior: a review.

Despite the many functions attributed to the frontal-lobe in previous writings and studies, empirically derived and reliable frontal-lobe abilities are limited and specific. Research that examines frontal-lobe dysfunction (as evidenced by neuropsychological tests that measure these specific abilities) and its relationship to antisocial behavior is reviewed. Frontal-lobe dysfunction is discussed in the context of the "minimal brain dysfunction" hypothesis of criminal behavior. Three studies reviewed examine criminal behavior, three examine specifically violent criminal behavior, and three focus on psychopathy. The nature of the research reviewed leaves the relationship between frontal-lobe neuropsychological dysfunction and crime open to further study.

Antisocial Personality Disorder↗
PubMed1995

Frontal lobe ataxia.

BACKGROUND: Gait abnormalities often result from disorders intrinsic to the cerebellum. Gait difficulties resulting from frontal lobe disease are less common but well recognized. The pathophysiologic mechanism of this type of ataxia is not well understood. One promising explanation implicates involvement of the frontopontocerebellar tract (Arnold's bundle). This tract originates in the frontal lobe in Brodmann's area 10 and carries information on intended movement to the contralateral cerebellum via the pontocerebellar peduncle. Interruption of this tract deprives the cerebellum of this information, thus impairing coordination and locomotion. METHODS: A patient is described with a large bilateral, medialorbital, frontal lobe lesion, progressive gait impairment, and dysarthria. The lesion is defined by magnetic resonance imaging (MRI) and positron emission tomography (PET) using 18-fluorodeoxyglucose. The cystic component of the lesion was drained surgically. RESULTS: The PET scan using 18-fluorodeoxyglucose showed a normal metabolic rate in the brain stem, a 10%-15% decrease in metabolism in the thalmus and a symmetric decrease of only 15% in the cerebellum bilaterally. The MRI of the cerebellum did not show any significant atrophy. The patient's speech improved, but there was minimal change in her gait ataxia after surgical drainage and partial removal of the cystic frontal lobe lesion. CONCLUSIONS: The patient's syndrome supports the view that frontal lobe ataxia is an established although rare clinical entity, and this report adds original information defining the syndrome with MRI and PET studies. The 15% metabolic decrease in the cerebellum with PET is highly supportive of the syndrome of frontal lobe ataxia and not pathology intrinsic to the cerebellum. The syndrome of frontal lobe ataxia in this patient is due to interruption of the frontopontocerebellar pathway originating in Brodmann's area 10.

Adolescent↗
PubMed1997

Relation between fluid intelligence and frontal lobe functioning in older adults.

This study reports the relations among normal aging, intelligence, and frontal lobe functioning. Intelligence tasks and frontal lobe functioning tasks were administered to 107 adults from two age groups (25 to 46 years and 70 to 99 years). Intelligence measures were assessed with two crystallized tests (WAIS Vocabulary and Information subtests), one fluid intelligence test (Cattell's Matrices), and one mixed, crystallized and fluid test (WAIS Similarities subtest). Frontal functioning was assessed using the Wisconsin Card Sorting Test (WCST) and two tests of verbal fluency. Significant age differences in favor of the young were found on the two intelligence tests with a fluid component and on all measures of frontal lobe functioning. Correlational analyses examining the relationship of intelligence measures to frontal variables indicated that these last measures were significantly correlated with only fluid intelligence tests in the elderly group. The implications for the relations among aging, fluid intelligence, and frontal lobe functioning are discussed.

Adult↗
PubMed1999

Frontal lobe psychopathology: mania, depression, confabulation, catatonia, perseveration, obsessive compulsions, and schizophrenia.

The frontal lobes can be subdivided into major functional neuroanatomical domains, which, when injured, surgically destroyed, or reduced in activity or volume, give rise to signature pathological and psychiatric symptomology. A review of case reports and over 50 years of research, including magnetic resonance imaging, positron emission tomography, and single photon emission computed tomography scans, indicates that apathy, "blunted" schizophrenia, major depression, and aphasic-perseverative disturbance of speech and thought are associated with left lateral as well as bilateral frontal (and striatal) abnormalities. Impulsiveness, confabulatory verbosity, grandiosity, increased sexuality, and mania are associated with right frontal (as well as bilateral) disturbances. Gegenhalten, catatonia, and disturbances of "will" are indicative of medial frontal injuries. Disinhibitory states and obsessive-compulsive perseverative abnormalities are more frequently observed with orbital frontal lobe dysfunction, including frontal-striatal disturbances. These associations, however, are not always clear-cut as patients with the same diagnosis may demonstrate different symptoms that may be due to an additional abnormality in a different region of the brain. Moreover, as the frontal subdivisions are richly interconnected, and as frontal lobe abnormalities are not always discrete or well localized, a wide array of seemingly divergent waxing and waning symptoms may be manifest, sometimes simultaneously, including manic depression and what has been referred to as the "frontal lobe personality."

Bipolar Disorder↗
PubMed2000

Executive functions and the frontal lobes: a conceptual view.

Several problems in understanding executive functions and their relationships to the frontal lobes are discussed. Data are then presented from several of our studies to support the following statements: (1) the examination of patients with focal frontal lobe lesions is a necessary first step in defining the relation of executive functions to the frontal lobes; (2) there is no unitary executive function. Rather, distinct processes related to the frontal lobes can be differentiated which converge on a general concept of control functions; (3) a simple control-automatic distinction is inadequate to explain the complexity of control-automatic processes; (4) the distinction between complex and simple tasks cannot explain the differences in functions between the frontal lobes and other brain regions; and (5) the most important role of the frontal lobes may be for affective responsiveness, social and personality development, and self-awareness and unconsciousness.

Attention↗
PubMed1997

Correlation of fetal frontal lobe and transcerebellar diameter measurements: the utility of a new prenatal sonographic technique.

Several authors have reported the value of the sonographic assessment of both the fetal frontal lobe and the cerebellum. Both frontal lobe shortening and cerebellar hypoplasia have been associated with fetal aneuploidy. We anecdotally observed that the distance between the calvarium and the posterior cavum septum pellucidum (frontal lobe) closely approximated the transcerebellar diameter. This study was undertaken to investigate this relationship. Between 1 July 1994 and 1 January 1996, the frontal lobe (posterior cavum septum pellucidum to the inner calvarium) and transcerebellar diameter were measured in patients referred to two prenatal ultrasound laboratories in Denver, Colorado, USA. All pregnancies had certain dates and were uncomplicated. Statistical comparison was completed using interval polynomial regression analysis. During the study period, we performed 221 detailed ultrasound examinations in which the frontal lobe and the transcerebellar diameter were measured. We found a correlation coefficient of 0.950 when comparing the two variables (p < 0.0001). Some conditions (Down's syndrome, lethal trisomies and pathological microcephaly) have differential effects on the frontal lobe and the transcerebellar diameter. Our preliminary judgement is that this new technique may prove to be a useful tool in assessing the relative effect of these conditions on structural neuroanatomy.

Adult↗
PubMed1998

Letter and category fluency in patients with frontal lobe lesions.

This study examines the hypothesis that patients with frontal lobe lesions are impaired on tests of letter but not category fluency. This hypothesis was proposed by Moscovitch (1994), based on a series of cognitive studies with young, normal participants. A group of patients with lateral prefrontal lesions and age-matched controls were tested on 2 tests of verbal fluency, the FAS task and a category fluency task that used semantic categories as cues (e.g., animals). Patients with frontal lobe lesions generated fewer items than controls on both letter and category fluency. This effect did not interact with the type of fluency test, suggesting that the frontal lobes are more generally involved in verbal fluency. Moreover, this pattern of findings, along with previous results of impaired free recall and remote retrieval in this patient group, suggests that patients with frontal lobe lesions do not efficiently organize and develop retrieval strategies.

Aged↗
PubMed2000

A new locus for autosomal dominant nocturnal frontal lobe epilepsy maps to chromosome 1.

BACKGROUND: Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is caused by mutations in the alpha4 subunit of the neuronal nicotinic acetylcholine receptor (CHRNA4) gene, mapping on chromosome 20q13.2. A second ADNFLE locus was mapped on chromosome 15q24. OBJECTIVE: To report a new third ADNFLE locus on chromosome 1 in a large Italian family. METHODS: The authors performed a clinical and genetic study in a large, three-generation ADNFLE family from southern Italy, including eight affected individuals and three obligate carriers. RESULTS: The age at onset of seizures was around 9 years of age and all affected individuals manifested nocturnal partial seizures of frontal lobe origin. Interictal awake and sleep EEG recordings showed no definite epileptiform abnormalities in most patients. Ictal video-EEG showed that the attacks were partial seizures with a frontal lobe semiology. Intellectual and neurologic examinations, and brain CT or MRI results were always normal. Carbamazepine was effective in all treated patients. Exclusion mapping of the known loci linked to ADNFLE-ENFL1, and ENFL2, on chromosomes 20q13.2 and 15q24-was performed on the pedigree before starting the genome-wide linkage analysis. The whole genome scan mapping allowed the identification of a new ADNFLE locus spanning the pericentromeric region of chromosome 1. CONCLUSIONS: The authors provided evidence for a third locus associated to autosomal dominant nocturnal frontal lobe epilepsy on chromosome 1. Among the known genes mapping within this critical region, the ss2 subunit of the nicotinic receptor (CHRNB2) represents the most obvious candidate.

Adolescent↗
PubMed1980

Blockade of ovulation and release of LH in the rat by electrochemical stimulation of the frontal lobe cortex.

The effect of stimulation of the frontal lobe cortex on the release of luteinizing hormone (LH) and ovulation was studied in female rats. Electrochemical stimulation (anodic DC) was applied through monopolar stainless-steel electrodes chronically implanted in the non-anesthetized freely-behaving animals bearing a plastic cannula inserted into the jugular vein for blood sampling. In rats, on the day of proestrus, stimulation (100 uA/30 sec) of the medial cortical surface in the superficial and deep layers of the medial precentral area and of the anterior cingulate area blocked ovulation in about 80% of the animals. A similar effect was seen when the stimulus was applied in the deep layers of the prelimbic and infralimbic areas. On the contrary, stimulation in the superficial layers of these latter two areas, as well as in the superficial and deep layers of the retrosplenial cortex, did not affect normal ovulation. The preovulatory discharge of LH was blocked in the animals which failed to ovulate. The degree of inhibition exerted by the anterior cingulate area and the prelimbic area on ovulation and LH surge was proportional to the amount of current applied. Stimulation of the anterior cingulate area also blocked the release of LH induced by the injection of progesterone into ovariectomized estrogen-primed rats. Furthermore, electrochemical stimulation of the anterior cingulate area inhibited the rise of LH in the serum induced by electrical stimulation of the medial preoptic area of ovariectomized estrogen-injected rats, but it failed to affect that resulting from electrical stimulation of the medial basal hypothalamus. On the other hand, stimulation of the lateral cortical surface and the ventral cortex of the frontal lobe on the day of proestrus affected normal ovulation and LH surge only when the stimulus was applied in the agranular insular area which also exhibited an inhibitory action. It is concluded that certain areas of the frontal lobe cortex related to limbic structures exert an inhibitory influence on ovulation and LH secretion.

Animals↗
PubMed1999

Frontal lobe atrophy and central motor conduction time in chronic alcoholics.

The central motor conduction time (CMCT) was investigated in 12 cases of chronic alcoholism with frontal lobe atrophy, 12 cases of chronic alcoholism without frontal lobe atrophy, and 12 age-matched healthy controls. The CMCT was significantly prolonged in the chronic alcoholics with frontal lobe atrophy as compared to the chronic alcoholics without frontal lobe atrophy and the healthy controls. A significant positive correlation was noted between the CMCT and the degree of frontal lobe atrophy. The CMCT may be prolonged in chronic alcoholics with frontal lobe atrophy.

Alcoholism↗