Assessment of Post-Stroke Consequences in Pediatric Ischemic Stroke in the Context of Neuroimaging Results-Experience from a Single Medical Center

Arterial ischemic stroke (AIS) in children is a rare condition; its frequency is estimated at 0.58 to 7.9 new onsets in 100,000 children per year. The knowledge on risk factors, clinical outcomes and consequences of pediatric AIS is increasing. However, there are still many unknowns in the field. The aim of the study was to analyze the clinical presentation of pediatric AIS and its consequences according to the neuroimaging results and location of ischemia. The research was retrospective and observational. The analyzed group consisted of 75 AIS children (32 girls, 43 boys), whereby the age of the patients ranged from 9 months to 18 years at stroke onset. All the patients were diagnosed and treated in one tertiary center. The most frequent stroke subtype was total anterior circulation infarct (TACI) with most common ischemic focus location in temporal lobe and vascular pathology in middle cerebral artery (MCA). The location of ischemic focus in the brain correlated with post-stroke outcomes: intellectual delay and epilepsy, hemiparesis corresponded to the location of vascular pathology. A correlation found between ischemic lesion location and vascular pathology with post-stroke consequences in pediatric AIS may be important information and helpful in choosing proper early therapy. The expected results should lead to lesser severity of late post-stroke outcomes.

Apathy following traumatic brain injury: A review

Apathy is a common problem after traumatic brain injury (TBI) and can have a major impact on cognitive function, psychosocial outcome and engagement in rehabilitation. For scientists and clinicians it remains one of the least understood aspects of brain-behaviour relationships encompassing disturbances of cognition, motivation, emotion and action, and is variously an indication of organic brain disease or psychiatric disorder. Apathy can be both sign and symptom and has been proposed as a diagnosis in its own right as well as a secondary feature of other conditions. This review considers previous approaches to apathy in terms of relevant psychological constructs and those neural counterparts most likely to be implicated after TBI. Neurobehavioural disorders of apathy are characterised chiefly by dysfunction of executive control of goal-oriented behaviour or the neural substrates of reward-based and emotional learning. We argue that it is possible to distinguish a primary disorder of apathy as an organic neurobehavioural state from secondary presentations due to an impoverished environment or psychological disturbance which has implications for treatment.

Independent and collaborative contributions of the cerebral hemispheres to emotional processing

Presented is a model suggesting that the right hemisphere (RH) directly mediates the identification and comprehension of positive and negative emotional stimuli, whereas the left hemisphere (LH) contributes to higher level processing of emotional information that has been shared via the corpus callosum. RH subcortical connections provide initial processing of emotional stimuli, and their innervation to cortical structures provides a secondary pathway by which the hemispheres process emotional information more fully. It is suggested that the LH contribution to emotion processing is in emotional regulation, social well-being, and adaptation, and transforming the RH emotional experience into propositional and verbal codes. Lastly, it is proposed that the LH has little ability at the level of emotion identification, having a default positive bias and no ability to identify a stimulus as negative. Instead, the LH must rely on the transfer of emotional information from the RH to engage higher-order emotional processing. As such, either hemisphere can identify positive emotions, but they must collaborate for complete processing of negative emotions. Evidence presented draws from behavioral, neurological, and clinical research, including discussions of subcortical and cortical pathways, callosal agenesis, commissurotomy, emotion regulation, mood disorders, interpersonal interaction, language, and handedness. Directions for future research are offered.

Abulia: a delphi survey of British neurologists and psychiatrists

Abulia is the relatively uncommon yet debilitating lack of spontaneous, goal-directed behaviour that is seen predominantly with lesions of the basal ganglia and the frontal lobes. We sought to confirm the existence of abulia as an entity recognized by clinicians, to generate a set of items characteristic of the condition, and to see how clinicians differentiate between overlapping disorders. The Delphi technique was used to survey consultant neurologists and psychiatrists at three hospitals in London. The study consisted of two phases: semi- structured interviews of a small group of neurologists and psychiatrists, followed by a survey of a larger group of consultants using postal questionnaires. Both neurologists and psychiatrists recognized abulia to be a distinct clinical entity but its status as a syndrome was unclear. Features such as difficulty in initiating and sustaining spontaneous movements and reduction in emotional responsiveness, spontaneous speech, and social interaction were identified as being characteristic of abulia. The information generated by this study may help to develop a working classification for disorders of diminished drive and motivation, and instruments for clinical assessment and decision making.

Isokinetic muscle performance in major depressive disorder: alterations by antidepressant therapy

The aims of this study were (i) to examine whether patients with major depressive disorder (MDD) differ from healthy control subjects with respect to isokinetic muscle performance (IMP) as measured by a dynamometer; (ii) to investigate the effect of subchronic treatment on the IMP in depressed patients. Thirty-eight patients with MDD, and 41 sex- and age-matched healthy controls participated in this study. The severity of depression and anxiety levels were evaluated by the Hamilton Depression and Anxiety Scales. Quadriceps and hamstring IMPs were determined by using an isokinetic dynamometer before and after subchronic antidepressant treatment. The patients had lower IMP levels than healthy controls. After treatment for three months with selective serotonin reuptake inhibitors, the IMP levels increased significantly. These findings suggest that (i) MDD may be characterized by reduced IMP levels; and (ii) treatment with antidepressants may increase the IMP levels, as a state marker for depression. It was concluded that (i) isokinetic muscle performance may be used as a state marker for monitoring antidepressant drug effects on MDD; (ii) isokinetic exercise increasing IMP may be used in the treatment of depression.

Isokinetic muscle performance in major depressive disorder: alterations by antidepressant therapy

The aims of this study were (i) to examine whether patients with major depressive disorder (MDD) differ from healthy control subjects with respect to isokinetic muscle performance (IMP) as measured by a dynamometer; (ii) to investigate the effect of subchronic treatment on the IMP in depressed patients. Thirty-eight patients with MDD, and 41 sex- and age-matched healthy controls participated in this study. The severity of depression and anxiety levels was evaluated by the Hamilton Depression and Anxiety Scales. Quadriceps and hamstring IMPs were determined by using an isokinetic dynamometer before and after subchronic antidepressant treatment. The patients had lower IMP levels than healthy controls. After treatment for three months with selective serotonin reuptake inhibitors, the IMP levels increased significantly. These findings suggest that (i) MDD may be characterized by reduced IMP levels; and (ii) treatment with antidepressants may increase the IMP levels, being a state marker for depression. It was concluded that (i) isokinetic muscle performance may be used as a state marker for monitoring antidepressant drug effects on MDD; (ii) isokinetic exercise increasing IMP may be used in the treatment of depression.

Frontostriatal deficits in unipolar major depression

Recent accounts of major depression have tended to focus on dysfunction of frontothalamic-striatal reentrant circuits as a possible source of the disorder. Evidence of frontostriatal involvement in unipolar major depression from lesion and neuropsychological studies, and functional and structural imaging studies is examined. The high incidence of depressive symptomatology following left frontal and basal ganglia lesions implicate these as possible sites of dysfunction. Neuropsychological evidence indicates similar deficits in patients with major depression, perhaps with dorsolateral prefrontal deficits most prominent. Structural imaging studies report frontal and basal ganglia (BG) abnormalities particularly in cases of late-age onset depression. Resting state functional imaging studies show deficits in dorsolateral, anterior cingulate (medial frontal), and BG structures. Activation imaging studies show less consistent evidence of dorsolateral deficit, while anterior cingulate deficit is more consistently demonstrated. Variability in findings across studies may reflect differences between subtypes of depression and differences in methodology. Possible involvement of the BG in the psychomotor retardation of depression is examined. It is concluded that, while there is evidence of frontostriatal deficit in major depression, the exact nature of such deficits is uncertain. Issues such as component vs. system dysfunction need to be addressed.

Frontal-subcortical circuits: the anatomic basis of executive, social and motivated behaviors

A series of discrete, parallel frontal-subcortical circuits have been demonstrated to link specific areas of the frontal lobe to areas within the basal ganglia and thalamus. A variety of circuit-specific behaviors can be described involving the dorsolateral prefrontal, orbitofrontal and anterior cingulate circuits. Interruptions or imbalance occurring at various levels within these closed looped circuits is felt to underlie the characteristic behavioral patterns seen. The intricate neurochemical arrangement of the striatum and the complex neurotransmitter interactions that occur within these key subcortical structures from the basis for modulatory influences that can affect these circuits.

Abulia and impulsiveness revisited: a conceptual history

Historical analysis suggests that the decline and fall of the will was due not to any major piece of empirical work demonstrating that the concept was unsound but to general changes in philosophical fashion, and to the temporary influence of the anti-mentalistic tenets of behaviorism and the anti-volitional assumptions of psychoanalysis. Clinical disorders like abulia and impulsiveness share conceptual features that 19th-century alienists captured well in their clinical category of disorder of the will. Current accounts, which include semi-explanatory concepts such as "drive", "motivation" or frontal lobe "executive" are not conceptually better than the old notion of will nor are they superior as correlational variables for neurobiological studies. It is suggested that the will, updated according to modern work in the philosophy of action, be re-adopted as a research category in current psychiatry.

The neuropsychology of schizophrenia: relations with clinical and neurobiological dimensions

It is now beyond question that the symptoms observed in schizophrenia include a range of cognitive neuropsychological deficits that may be more enduring than psychotic symptoms (Cassens et al. 1990; Goldberg et al. 1993) Goldberg et al. (1993) found that a group of patients treated with clozapine whose psychotic symptoms improved significantly over a 15 month study period showed no improvement in cognitive impairments. He argued that the enduring cognitive deficits are responsible for failure of patients to rehabilitate socially even when psychotic symptoms are in remission. Clearly an understanding of neuropsychological deficits is Important from a clinical as well as a theoretical viewpoint. There is, however, still much debate about the nature of these deficits and how they related to the psychotic symptoms of schizophrenia and also to the neurobiological substrate of this disorder.

Ventricular enlargement and caudate hyperdensity in elderly depressives

Twenty-five elderly patients (mean age 73 years, range 61-88 years) with major depression underwent cranial computed tomography (CT). The findings were compared with healthy age- and sex-matched controls. The radiodensity of the left and right heads of the caudate was significantly higher in the depressed patients (p less than 0.05). The third ventricle was significantly enlarged (p less than 0.05); this effect did not reach statistical significance for the lateral ventricles. Ventricle size in the patient sample increased with age, duration of illness, and number of depressive episodes. This effect was largely age-driven for the third ventricle. Enlargement of the anterior horns appeared to be primarily influenced by the combined effects of early onset and bipolarity of illness. Densitometric measurements of the grey and white matter did not show significant correlations with age, number, or frequency of depressive episodes, age of onset, or duration of illness.