The following are my notes on Principles of Neural Science, an influential neuroscience textbook edited by Eric R. Kandel, James H. Schwartz, and Thomas M. Jessell.
1.1 — Relationship between Brain and Behaviour
— Five experimental traditions: Anatomy, Embryology, Physiology, Pharmacology and Psychology.
—Gall’s theory of localization — Phrenology — Complex traits such as hope, spirituality, and conscientiousness are controlled by specific areas in the brain, which expand as the traits develop — Experimentally false.
— Cellular connectionism — Individual neurons are signalling units of brain; they are arranged in functional groups and connect to one another in a precise fashion.
— The central nervous system — 7 parts
Spinal cord, rostral to the brain stem — Receives and processes sensory information from skin, joints, and muscles of the limb and trunk and controls movement — subdivided into cervical, thoracic, lumbar, and sacral regions.
Medulla oblongata, rostral to the spinal cord — Responsible for digestion, breathing, and control of heart rate.
Pons, rostral to medulla — Conveys information about movement from cerebral hemispheres to the cerebellum.
Cerebellum, behind pons, connected by brain stem by penduncles, major fiber tracs — Modulates the force and range of movements — Involved in learning of motor skills.
Midbrain, rostral to pons — Controls many sensory and motor functions — Eye movement and coordination of visual and auditory reflexes.
Diencephalon, lies rostral to midbrain — Consist of Thalamus and Hypothalamus — Thalamus processes most of info reaching the cerebral cortex from rest of central nervous system — Hypothalamus regulates autonomic, endocrine, and visceral functions.
Cerebrum, comprises of two cerebral hemispheres — Consisting of cerebral cortex(heavily wrinkled outer layer) and 3 deep underlying structure (the basal ganglia, the hippocampus, and the amygdaloid nuclei) — basal ganglia participate in regulating motor performance — the hippocampus is involved with aspects of memory storage — the amygdaloid nuclei coordinate the autonomic and endocrine responses of emotional states.
— Cerebral cortex — frontal, parietal, occipital, and temporal lobes — Crest of convolutions surrounding them is gyri — Intervening grooves are called sulci or fissures.
— Frontal lobe — short term memory, planning future actions and with control of movement.
— Parietal lobe — somatic sensation, with forming a body image and relating it to extrapersonal space.
— Occipital lobe — vision.
— Temporal lobe — hearing and — through its deep structures, the hippocampus and amygdaloid nuclei — with learning, memory, and emotion.
— Each hemisphere is concerned primarily with sensory and motor processes on the contralateral (opposite) side of the body.
— Hemispheres, though similar in appearance, are neither completely symmetrical in structure nor equivalent in function.
1.2 — The First Strong Evidence for Localization of Cognitive Abilities Came from Studies of Language Disorders
— Aphasia, a language disorder due to certain brain tissues destroyed by a stroke, occlusion or rupture of blood vessel.
— Areas involved in language — Wernicke’s area processes auditory input for language and is important for understanding speech. It lies near the primary auditory cortex and the angular gyrus, which combines auditory input with information from other senses — Broca’s area controls the production of intelligible speech. It lies near the region of the motor area that controls the mouth and tongue movements that form words
— Wernicke’s area communicates with Broca’s area by a bidirectional pathway, part of which is made up of the arcuate fasciculus.
— The existence of universal grammar, implies that there is an innate system in the human brain that evolved to mediate this grammatical design of language.
— Artificial language, a language that violates the rules of universal grammar, activity in Broca’s area does not increase.
— Broca’s area must contain some kind of constraints that determine the structure of all natural languages.
1.3 — Affective States Are Also Mediated by Local, Specialized Systems in the Brain
— Some aphasic patients have trouble with the affective aspects of language, such as intonation (prosody).
— Damage to the right temporal area corresponding to Wernicke’s area in the left temporal region leads to disturbances in comprehending emotional aspects of speech.
— Damage to the right frontal area corresponding to Broca’s area leads to difficulty in expressing emotional aspects of speech.
— Amygdala, lies deep within the cerebral hemispheres.
— Its role in emotion was discovered through studies of the effects of the lesions within the temporal lobe that produce epilepsy.
— The consequences of irritative lesions are exactly the opposite of those of destructive lesions resulting from a stroke or injury. Whereas destructive lesions bring about loss of function, often through the disconnection of related functional systems, the electrical activity brought about by epilepsy can increase activity in the regions in which the epileptic seizure occurs. In the case of amygdala seizures the increased activity leads to excessive expression of emotion.
— Consciousness is a global property of the brain that involves vast numbers of nerve cells and a complex system of feed-forward broadcasting and feedback reentrant circuits.
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