Neuroscience Lecture 2 2024.pdf

Psychology 1002: Neuroscience Lecture 2 The Brain Large clump of ~87 billion neurons Responsible for complex behaviours, thought, perception, and emotion. Two hemispheres (left and right,...

Psychology 1002: Neuroscience Lecture 2 The Brain Large clump of ~87 billion neurons Responsible for complex behaviours, thought, perception, and emotion. Two hemispheres (left and right, mirror images) 2  The Ventricles Cavities filled with cerebrospinal fluid (CSF) Sewerage system of CNS Blockage causes hydrocephalus (inflates ventricles, squashing brain) 3  Major subdivision of the brain 1. Brainstem controls life-supporting functions Damage following head injury leads to coma and death. 4  Major subdivision of the brain 2. Cerebellum (“small brain”) Control of precision movements (including learned ones) 5  Major subdivision of the brain 3. Thalamus & hypothalamus (diencephalon) Thalamus is sensory relay to cortex (and more) Hypothalamus is involved in hormonal regulation and motivational control (feeding and sex) 6  Major subdivision of the brain 4. Limbic system: control of emotion and memory Fornix Thalamus Cingulate cortex Hippocampus Amygdala Olfactory Mammillary bodies bulb (in hypothalamus) 7  Major subdivision of the brain 5. Basal ganglia: action and thought. Thalamus (left and right) Caudate (right) Caudate (left) Globus Putamen Pallidus 8  Major subdivision of the brain 6. Neocortex: convoluted sheet on top of brain 9 Four lobes of neocortex 1. Frontal Lobes; 2. Parietal lobes; 3. Temporal lobes; 4. Occipital lobes 13  Four lobes of neocortex Frontal Lobes: planning and executive functions Motor Touch control Parietal lobes: representing space for action Temporal lobes: memory and language Occipital lobes: vision Taste and smell Hearing 14  Major subdivision of the brain 7. Corpus Callosum: connecting two hemispheres 15  Comparative Neuroanatomy Nervous System almost a defining feature of animals. Roundworm (c. elegans) has 302 neurons Starfish have ~ 500 neurons “nerve nets” in jellyfish [5,000 – 10,000 neurons] Nervous System has more complex organization in insects:  clusters of neurons (“ganglia”) forming cord or “brain”.  some specialisation of neurons (e.g., motor vs sensory). 17 ¼ million 1 million  Comparative Neuroanatomy Vertebrates have separation between PNS and CNS. midbrain telencephalon spinal cord diencephalon hindbrain 18 Forebrain  Comparative Neuroanatomy Among vertebrates, large differences in relative size of different regions of brain, reflecting complexity of behaviour. Olfactory bulb Fish Frog Alligator Forebrain Midbrain Cerebellum Hindbrain Goose Cat Human Large increase in size of forebrain across vertebrates; appearance (and enlargement) of neocortex in mammals. 19