International Journal of Neuroscience

doi: 10.3109/00207459309024102pmid: 8138370

Tan, Üner; Zor, Nevin; Kücüközkan, Tuncay; Akcay, Fatih; Yigitoglu, Ramazan; Bakan, Ebubekir; Kutlu, Necip

doi: 10.3109/00207459309024103pmid: 8138371

Grasp reflex and its asymmetry was studied in relation to pH of the umbilical blood in human newborns, to examine whether the degree of acidity in fetal blood (birth stress) is associated with cerebral laterality. Low pH values were considered as an index for birth stress. Grasp-reflex strength was found to be directly related to pH in total sample. There were sex-related differences. Namely, this correlation was true only for female newborns, not for males. Right minus left grasp-reflex strength linearly increased with pH, i.e., low pH values were associated with left-hand dominance, but only in males. The grasp-reflex asymmetry was not related to pH in females. It was concluded that blood pH may be associated with motor asymmetry and motor development in human newborns, but show sex-related differences; female brain seemed to be more sensitive to pH changes than male brain. The results partly supported the Bakan's hypothesis that birth stress may be associated with left-handedness.

Lee, Gregory P.; Loring, David W.; Meador, Kimford J.

doi: 10.3109/00207459309024104pmid: 8138372

Both premorbid personality characteristics and location of brain lesion have been proposed to account for emotional changes after cerebral damage. To explore the relative merits of each hypothesis, we compared the MMPI profiles of 30 epileptic patients, who showed either a euphoric or depressive reaction after injection of amobarhital into the right or left hemisphere, with the MMPI profiles of 30 matched controls. There were no significant T-score differences between euphoric, depressed, or control patients on any of the MMPI scales. However, more patients with euphoric (42%) than depressed (0%) reactions had hypomania (scale 9) scores greater than 70 T. With regard to location of lesion, there was a statistically significant association between emotional reaction and side of amobarbital brain inactivation. Euphoria was more frequent following right, and depression was more common after left, hemisphere inactivation. Although support was found for both premorbid personality and lesion location in the genesis of emotional reactions after brain damage, results were more robust for location of lesion.

Hernandez, A.; Contreras, E.; Paeile, C.; Pérez, H.; Pelissier, T.; Quijada, L.; Soto-Moyano, R.

doi: 10.3109/00207459309024105pmid: 7511132

The role of L-type Ca2+ channels on the kappa opioid-induced depression of spinal afferent transmission was assessed in spinalized rats, through recording of the C-fiber-evoked spinal flexor reflex. Six successive i.t. doses of the K agonist U-50.488H produced a dose-dependent decrease of the C-reflex duration (ID50 : 25.7 nmol), the log dose-response relationship being shifted to left by pretreatment with 5 mg/kg i.v. of the calcium channel blocker verapamil, or to right by pretreatment with. 25 mg/kg i.v. of the calcium channel agonist Bay K8644. Verapamil and Bay K8644, administered i.v. after U-50.488H i.t., respectively potentiated or antagonized the depressor effect of the K ligand on the reflex. The results point to a role for Ca2+ availability as a factor involved in depression of afferent nociceptive transmission by K opioids at the spinal cord

Gabbard, Carl

doi: 10.3109/00207459309024106pmid: 8138373

Recent reports suggest that footedness warrants consideration as a potentially useful measure of specific aspects of neuropsychological functioning. However, very few data are available concerning its developmental characteristics. This paper presents a review of studies describing the trichotomous distribution of foot laterality spanning the childhood years (ages 3- to 11). When compared to handedness characteristics in the same population, it was noted that right-side dominance (foot preference) was not as pronounced, and about twice as many exhibit no dominant limb (i.e., mixed). The predictable pattern of increasing right-sidedness with advancing age found in handedness was not obvious for foot laterality over this period of time. The mixed-footed phenomenon is addressed using the basic tenets of Annett's Right-Shift hypothesis and the unique cultural factors associated with foot behavior. Applied implications of these observations for neuropsychological assessment and motor skill instruction are discussed.

Ji, Ru-Rong; Zhang, Zhi-Wen; Zhou, Yan; Zhang, Qin; Han, Ji-Sheng

doi: 10.3109/00207459309024107pmid: 8138374

The present study was designed to examine the induction of c-fos mRNA and Fos-like protein in the rostral medulla of awake rats following electroacupuncture (EA) stimulation, using in situ hybridization and immunohistochemical method. Rats were subjected to EA stimulation (100 Hz, 1–2–3 mA) for 30 min by inserting two needles into acupoints Zusanli (S36) and Sanyingjiao (Sp6) of each hind leg. Animals were sacrificed 1h and 2h after EA for in situ hybridization and immunohistochemical study, respectively, c-fos mRNA or Fos-like-immunoreactivity (FLI) neurons were densely distributed in the rostral ventromedial medulla (RVM). including raphe magnus nucleus, gigantocellular reticular nucleus, gi-gantocellular reticular nucleus alpha, as well as intermediate reticular nucleus. Neurons in the solitary tract nucleus also showed c-fos expression. The results suggest that the RVM may be an important region for mediating EA effect.

Puente, Antonio E.; Rodenbough, John; Orrell, Timothy D.

doi: 10.3109/00207459309024108pmid: 7908012

Four groups of 20 each (chronic brain-damaged schizophrenics, chronic non-brain-damaged schizophrenics, chronic non-brain-damaged with “acute” exacerbation, and control subjects) were individually administered Form I of the Luria Nebraska Neuropsychological Battery (LNNB). Control subjects scored significantly lower than all clinical groups on all scales except for the chronic non-brain-damaged schizophrenics on the Reading Scale. “Acute” schizophrenics scored higher on Motor, Visual, Receptive Speech, Intellectual Processes, Pathognomonic, Right Hemisphere and Profile Elevations scales than the other clinical groups. Chronic brain-damaged schizophrenics scored significantly higher than chronic non-brain-damaged schizophrenics on the Profile Elevation scale. To examine the possibility that LNNB performance of the schizophrenic groups may have been related to neuroleptic medication, analyses were completed on the relationship between medication levels and LNNB scores. These results suggested that while the three clinical groups differed in their chlorpromazine equivalents (CPZE), LNNB scores were not related to CPZE dosage.

Demakis, George J.; Harrison, David W.; Campen, Matthew

doi: 10.3109/00207459309024109pmid: 8138375

Kinsbourne's selective activation model (1985) was investigated in a sample of 28 strongly right-dominant males. Priming manipulations were hypothesized preferentially to activate a hemisphere and to decrease reaction time on an affect recognition task in the contralateral visual field. The left hemisphere manipulation consisted of subvocal verbal rehearsal, while imagery served as the right hemisphere task. Baseline performance was evaluated via a control condition. No priming was found, but the experimental tasks had significant interference effects. Interference was noted across visual fields for both experimental manipulations relative to the control condition, suggesting the hemispheres were not preferentially recruited. Furthermore, the processing of happy faces was more susceptible to interference than was that of angry faces. Conceptual and methodological issues are presented to account for the former finding and data relevant to the laterality of affect perception may explain the latter.

Levine, Daniel S.; Parks, Randolph W.; Prueitt, Paul S.

doi: 10.3109/00207459309024110pmid: 8138376

Neural network models have made significant strides in recent years toward modeling of neuropsycho-logical data. in particular, three different research groups, including that of the present authors, have simulated in model networks some of the behavioral effects of frontal lobe damage. in this article we review these models and discuss their significance in terms of hierarchical organization in the nervous system. These models, to varying degrees, incorporate several widely used neural network principles that have also been used to model a wide range of data in other areas such as categorization, conditioning, and motor control. These principles include associative learning, competition, opponent processing, neu-romodulation, and interlevel resonant feedback. Specifically, we show how combinations of these principles serve to model the attentional requirements of cognitive tasks and motor plans.

Tan, Üner

doi: 10.3109/00207459309024111pmid: 8138377

Speed and accuracy in hand speed in relation to sex-related differences were studied in left-handed normal subjects. Hand skill was assessed by a peg moving task. Hand speed increased linearly with successive trials (motor learning). Left-hand speed exhibited a higher learning capacity than right-hand speed. Right-hand speed and right-hand learning were equivalent in males and females. Left-hand speed was higher in females than males; left-hand learning was equivalent in males and females. Left minus right (L-R) hand speed decreased linearly with right-hand speed; left-hand speed did not influence L-R hand speed. Learning curves were constructed for each subject. Standard error of a learning curve was considered as accuracy of hand skill. In females, accuracy of hand movement decreased as hand speed increased. In males, only accuracy of right-hand speed decreased as right-hand speed increased; left-hand accuracy did not depend on left-hand speed. It was concluded that right brain controlling left hand in left-handers has a higher capacity than left brain for motor learning; L-R hand speed was largely determined by left brain; accuracy in hand skill depends on both brains in females, and on only left brain in males; the female brain is more bilaterally organized than male brain in fine motor control.