There is disagreement in the literature about the exact nature of the phenomenon of empathy. There are emotional, cogni- tive, and conditioning views, applying in varying degrees across species. An adequate description of the ultimate and proximate mecha- nism can integrate these views. Proximately, the perception of an object's state activates the subject's corresponding representations, which in turn activate somatic and autonomic responses. This mechanism supports basic behaviors (e.g., alarm, social facilitation, vicar- iousness of emotions, mother-infant responsiveness, and the modeling of competitors and predators) that are crucial for the reproduc- tive success of animals living in groups. The Perception-Action Model (PAM), together with an understanding of how representations change with experience, can explain the major empirical effects in the literature (similarity, familiarity, past experience, explicit teach- ing, and salience). It can also predict a variety of empathy disorders. The interaction between the PAM and prefrontal functioning can also explain different levels of empathy across species and age groups. This view can advance our evolutionary understanding of empa- thy beyond inclusive fitness and reciprocal altruism and can explain different levels of empathy across individuals, species, stages of de- velopment, and situations.

/pdf/empathy-its-ultimate-and-proximate-bases-3gnr9okjki.pdf

Empathy: Its ultimate and proximate bases.

This paper reviews the literature on the Nl wave of the human auditory evoked potential. It concludes that at least six different cerebral processes can contribute to (he negative wave recorded from the scalp with a peak latency between 50 and 150 ms: a component generated in the auditory-cortex on the supratemporal plane, a component generated in the association cortex on the lateral aspect of the temporal and parietal cortex, a component generated in the motor and premotor cortices, the mismatch negativity, a temporal component of the processing negativity, and a frontal component of the processing negativity, The first three, which can be considered ‘true’ N1 components, are controlled by the physical and temporal aspects of the stimulus and by the general state of the subject. The other three components are not necessarily elicited by a stimulus but depend on the conditions in which the stimulus occurs. They often last much longer than the true N1 components that they overlap.

The N1 wave of the human electric and magnetic response to sound: a review and an analysis of the component structure

Foreword by Norbert Hornstein Preface Part I 1 Mind and Body 2 Structures, Capacities, and Conventions 3 Knowledge of Grammar 4 Some Elements of Grammar Part II 5 On the Biological Basis of Language Capacities 6 Language and Unconscious Knowledge Notes Index

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/BB96E4E09C461EFC230F72A9D7BDF603/S0140525X00001515a.pdf/div-class-title-rules-and-representations-div.pdf

Rules and Representations

How the immense population of neurons that constitute the human cerebral neocortex is generated from progenitors lining the cerebral ventricle and then distributed to appropriate layers of distinctive cytoarchitectonic areas can be explained by the radial unit hypothesis. According to this hypothesis, the ependymal layer of the embryonic cerebral ventricle consists of proliferative units that provide a proto-map of prospective cytoarchitectonic areas. The output of the proliferative units is translated via glial guides to the expanding cortex in the form of ontogenetic columns, whose final number for each area can be modified through interaction with afferent input. Data obtained through various advanced neurobiological techniques, including electron microscopy, immunocytochemistry, [3H]thymidine and receptor autoradiography, retrovirus gene transfer, neural transplants, and surgical or genetic manipulation of cortical development, furnish new details about the kinetics of cell proliferation, their lineage relationships, and phenotypic expression that favor this hypothesis. The radial unit model provides a framework for understanding cerebral evolution, epigenetic regulation of the parcellation of cytoarchitectonic areas, and insight into the pathogenesis of certain cortical disorders in humans.

http://science.sciencemag.org/content/sci/241/4862/170.full.pdf

Specification of cerebral cortical areas

Vulnerable periods during the development of the nervous system are sensitive to environmental insults because they are dependent on the temporal and regional emergence of critical developmental processes (i.e., proliferation, migration, differentiation, synaptogenesis, myelination, and apoptosis). Evidence from numerous sources demonstrates that neural development extends from the embryonic period through adolescence. In general, the sequence of events is comparable among species, although the time scales are considerably different. Developmental exposure of animals or humans to numerous agents (e.g., X-ray irradiation, methylazoxymethanol, ethanol, lead, methyl mercury, or chlorpyrifos) demonstrates that interference with one or more of these developmental processes can lead to developmental neurotoxicity. Different behavioral domains (e.g., sensory, motor, and various cognitive functions) are subserved by different brain areas. Although there are important differences between the rodent and human brain, analogous structures can be identified. Moreover, the ontogeny of specific behaviors can be used to draw inferences regarding the maturation of specific brain structures or neural circuits in rodents and primates, including humans. Furthermore, various clinical disorders in humans (e.g., schizophrenia, dyslexia, epilepsy, and autism) may also be the result of interference with normal ontogeny of developmental processes in the nervous system. Of critical concern is the possibility that developmental exposure to neurotoxicants may result in an acceleration of age-related decline in function. This concern is compounded by the fact that developmental neurotoxicity that results in small effects can have a profound societal impact when amortized across the entire population and across the life span of humans.

Critical periods of vulnerability for the developing nervous system: evidence from humans and animal models.

Part two of this three-part series commences with anomalous dominance and special talents. Part one appears in a previous issue of theArchives. 1 ANOMALOUS DOMINANCE AND SPECIAL TALENTS According to our hypothesis, slowed growth within certain zones of the left hemisphere is likely to result in enlargement of other cortical regions, in particular, the homologous contralateral area, but also adjacent unfaffected regions. The influences that favor anomalous dominance may thus favor talents associated with superior development of certain regions either in the right hemisphere or in adjacent parts of the left hemisphere. Even with excessive retardation of growth and the resultant migration abnormalities and learning disorders (LD), high talents may exist as a result of compensatory enlargement of other cortical regions. Several types of data are in concordance with these conclusions. Several studies have claimed that the average level of spatial talents is higher in male subiects. 2 Hier

https://jamanetwork.com/journals/jamaneurology/articlepdf/584161/archneur_42_5_008.pdf

Cerebral lateralization. Biological mechanisms, associations, and pathology: II. A hypothesis and a program for research.

We report an experimental study designed to test the following hypothesis derived from clinical observations: There is an elevated frequency in left-handed individuals and in their families of immune disease, migraine, and developmental learning disorders. In two separate investigations the frequency of these conditions was compared in strongly left-handed subjects and in strongly right-handed controls. In each of the investigations we found markedly higher frequencies of immune disease in the left-handers than in the right-handers. The rate of learning disabilities was also much higher in the left-handers than in the right-handers in both investigations. In a second study the frequency of left-handedness was compared in patients with migraine or immune disease and in general population control subjects free of these disorders. There was a higher frequency of left-handedness in patients with migraine and myasthenia gravis than in controls. We present a brief outline of a hypothesis that may account for an increased frequency of immune disease in left-handers and in their families.

https://www.pnas.org/content/pnas/79/16/5097.full.pdf

Left-handedness: association with immune disease, migraine, and developmental learning disorder.

• Three retrospective studies were conducted to examine functional brain asymmetry in the regulation of emotion. In the first study, reports of 119 cases were collected of pathological laughing and crying associated with destructive lesions. Pathological laughing was associated with predominantly right-sided damage, whereas pathological crying was associated with predominantly left-sided lesions. In the second study, 19 reports detailing mood following hemispherectomy were collected; right hemispherectomy was associated with euphoric mood change. In the third study, lateralization of epileptic foci was assessed in reports of 91 patients with ictal outbursts of laughing (gelastic epilepsy). Foci were most likely to be predominantly left-sided. The findings are congruent with studies of the effects of unilateral brain insult on mood, and a general model of hemispheric asynmetry in the regulation of emotion is presented.

Hemispheric Asymmetry in the Expression of Positive and Negative Emotions: Neurologic Evidence

• The auditory regions in four normal brains were mapped and the full extent of the cytoarchitectonic subdivisions was measured for the presence of right-left asymmetries. It was found that asymmetries similar to those found in the planum temporale (left commonly larger than right) are also seen in auditory cytoarchitectonic area Tpt, an area of probable importance for language function. There is a strong positive correlation between the planum asymmetry and the asymmetry of Tpt. It is concluded that the previously described planum asymmetries probably reflect asymmetries in an auditory cytoarchitectonic area and therefore may represent, at least in part, the anatomic substrate for language lateralization.

Human Brain: Cytoarchitectonic Left-Right Asymmetries in the Temporal Speech Region

• Twenty consecutive men with partial seizures of temporal lobe origin were evaluated for sexual or reproductive dysfunction. Eleven (55%) had diminished sexual interest or reduced potency. Nine of them had reproductive endocrine disorders, with features of hypogonadotropic hypogonadism in five, hyperprolactinemia in two, and hypergonadotropic hypogonadism in two. Among these nine were cases in which the reproductive endocrine abnormalities could not readily be attributed to antiseizure medication use. Other possible interpretations are as follows: (1) epileptic discharges in medial temporal lobe structures may disrupt hypothalamic regulation of pituitary secretion, (2) hypogonadism may promote the development of epileptic discharges, and (3) temporal lobe epilepsy and associated reproductive endocrine disorders may represent the parallel effects of prenatal factors common to the development of both the brain and the reproductive system.

Norman Geschwind

Papers

Cerebral lateralization. Biological mechanisms, associations, and pathology: II. A hypothesis and a program for research.

Left-handedness: association with immune disease, migraine, and developmental learning disorder.

Hemispheric Asymmetry in the Expression of Positive and Negative Emotions: Neurologic Evidence

Human Brain: Cytoarchitectonic Left-Right Asymmetries in the Temporal Speech Region

Reproductive endocrine disorders in women with partial seizures of temporal lobe origin.