AQA Psychology - Biopsychology Flashcards

Flashcards covering the nervous system, types of neurons, synaptic transmission, the endocrine system, and brain scanning techniques based on AQA Psychology Biopsychology notes.

Nervous system

Coordinates actions by transmitting signals to/from body parts.

Neurons

Approximately $100$bn in the human NS, with $80\%$ located in the brain; they transmit signals electrically and chemically around the body in one direction.

Central Nervous System (CNS)

Responsible for complex processing of information and decision-making; comprised of the brain and spinal cord.

Cerebral cortex

A highly developed part of the brain that distinguishes higher order functioning in humans compared to other animals.

Peripheral Nervous System (PNS)

Connects the CNS to the rest of the body, bringing sensory info to the CNS and transmitting info from the CNS to muscles and glands.

Somatic Nervous System

Part of the PNS involved in conscious/voluntary actions and reflex actions that don't pass through the CNS.

Autonomic Nervous System (ANS)

Part of the PNS responsible for involuntary actions like heart rate, digestion, and breathing; divided into sympathetic and parasympathetic branches.

Sympathetic Nervous System (SNS)

Activates the fight or flight response, increasing HR/BP and slowing less important functions like digestion.

Parasympathetic Nervous System

Known for 'rest and digest'; promotes relaxation after a stressful event and returns the body to homeostasis.

SLUDD

Mnemonic for the parasympathetic NS: Salivation, Lacrimation, Urination, Digestion, Defecation.

Sensory neurons

Carry messages from the peripheral NS to the CNS; they have long dendrites and short axons.

Relay neurons

Mainly located in the CNS, they connect sensory to motor neurons and have short dendrites and short axons.

Motor neurons

Carry nerve impulses from the CNS to effectors (muscles/glands) and feature short dendrites and long axons.

Nodes of Ranvier

Gaps in the myelin sheath that speed up transmission by forcing the electrical impulse to jump (saltatory conduction).

Synaptic transmission

The process where an electrical impulse is converted to a chemical signal to cross the synapse before returning to an electrical one.

Excitation

Occurs when excitatory neurotransmitters like adrenaline increase the positive charge in the postsynaptic neuron, increasing the likelihood it will fire.

Inhibition

Occurs when inhibitory neurotransmitters like serotonin increase the negative charge in the postsynaptic neuron (hyperpolarisation), decreasing the likelihood it will fire.

Summation

The process of adding up the inhibitory and excitatory influences to determine if a postsynaptic neuron will fire.

Psychological Evaluation: Reductionism

The critique that biological explanations reduce complex human experiences to simple outcomes of genes or chemical processes, ignoring social factors.

Endocrine system

A chemical communication system that works alongside the nervous system, using glands to secrete hormones into the bloodstream.

Pituitary gland

The 'Master gland' located at the base of the brain; produces ACTH and oxytocin.

Adrenal medulla

Part of the adrenal glands that releases adrenaline and noradrenaline to stimulate the sympathetic NS.

Adrenal cortex

Part of the adrenal glands that produces cortisol to provide energy for prolonged stress by mobilising glucose/fat.

Pineal gland

Produces melatonin to regulate sleep patterns and synchronise the sleep-wake cycle.

SAM pathway

The Sympathomedullary pathway designed to facilitate coping with acutely stressful situations.

Beta bias (Stress)

Refers to early research (e.g., Taylor et al.) that used male animals or men, assuming the fight or flight response is universal and ignoring female differences.

Tend and befriend

A suggested alternative stress response in women, linked to oxytocin, involving protecting offspring and seeking social support.

Freeze effect

Identified by Karin Roelofs; an instinct to stay immobile or dissociate, caused by the SNS and PSNS firing simultaneously.

Temporal resolution

The accuracy of a brain scanner in relation to time, or how quickly it detects changes in activity.

Spatial resolution

The smallest feature or measurement a scanner can detect; higher resolution allows for better discrimination between brain regions.

fMRI

Magnetic resonance imaging that measures oxygenated blood flow using voxels to create activation maps; has good spatial resolution but a $5$ second delay.

EEG

Electroencephalogram; records electrical activity via electrodes on the scalp to show brainwaves; high temporal resolution but limited anatomical specificity.

Post-mortem examinations

The analysis of a brain after death; used to establish relationships between brain damage and behavior, such as Broca and Wernicke's work.