8th Class

Memory and Neural Mechanisms

Long-term Memory Stabilization

  • Involves signaling cascades where molecules can excite or inhibit each other.

  • Activator pin one (PIN1) modifies enzymes influencing memory formation.

  • Activated memories can persist unless replaced by new information or compromised by competing memories.

  • Epileptic mechanisms show how feedback loops can lead to seizures, illustrating memory fragility.

Sensation and Perception

Introduction

  • Sensation: Initial reception of stimuli from the environment.

  • Perception: Brain's interpretation of sensory signals.

Sensory Deprivation Chambers

  • Remove sensory input to promote relaxation and meditation; experiences may lead to vivid hallucinations.

Perception in Non-Human Species

  • Species differ in sensory capabilities; plants exhibit phototropism, and single-celled organisms make basic decisions.

  • Multiple senses enhance adaptability; loss of one can affect survival.

Differentiating Sensation and Perception

  • Sensation converts energy into neural signals; Perception interprets these signals.

  • Personal and cultural factors affect subjective experiences.

Changes in Sensitivity

  • Taste preferences can evolve over time; aging may reduce taste and smell sensitivity.

Properties of Sensory Systems

  • Key Properties:

    • Range of Response: Sensitivity to varied stimuli.

    • Adaptation: Receptors respond rapidly to new stimuli.

    • Acuity: Ability to distinguish different stimuli levels.

Auditory System

Anatomy of Hearing

  • Outer ear captures sound; vibrations pass through the eardrum and ossicles to the cochlea, where hair cells convert fluid motion into neural activity.

Sound Properties

  • Amplitude affects loudness; Frequency affects pitch.

Olfactory System

Understanding Smell

  • Olfactory processing bypasses the thalamus for rapid odor identification; involves Conditioned Taste Aversion to avoid harmful substances.

Unique Aspects of Olfactory Processing

  • Olfactory information is processed on the same brain side.

  • Dogs adapt sniffing techniques to target specific scents, showing sophisticated olfactory ability.